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Title:
MASS TRANSFER
Document Type and Number:
WIPO Patent Application WO/2010/081193
Kind Code:
A1
Abstract:
The present invention relates to methods for transferring liquid into a solid comprising applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid.

Inventors:
BATES DARREN M (AU)
Application Number:
PCT/AU2010/000028
Publication Date:
July 22, 2010
Filing Date:
January 13, 2010
Export Citation:
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Assignee:
CAVITUS PTY LTD (AU)
BATES DARREN M (AU)
International Classes:
A23B7/02; B01J19/10
Domestic Patent References:
WO1999031026A11999-06-24
Foreign References:
JPS60197208A1985-10-05
DE3401847A11985-08-01
SU1050635A11983-10-30
US5198122A1993-03-30
JPH03252541A1991-11-11
CN101012510A2007-08-08
US20070120088A12007-05-31
Other References:
ALFRED WEISSLER: "Sonochemistry: The production of Chemical Changes with Sound Waves", J. ACUSTICA. SOC. OF AMERICA, vol. 25, no. 4, July 1953 (1953-07-01), pages 651 - 657
Attorney, Agent or Firm:
SPRUSON & FERGUSON (Sydney, New South Wales 2001, AU)
Download PDF:
Claims:
Claims:

1. A method for transferring liquid into a solid comprising applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid.

2. A method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) applying heat to the mixture.

3. The method of claim 2 wherein the heat and highly propagating ultrasonic energy act synergistically to transfer the liquid into the solid.

4. A method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) applying pressure to the mixture.

5. The method of claim 4 wherein the pressure and highly propagating ultrasonic energy act synergistically to transfer the liquid into the solid.

6. A method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) homogenising the mixture.

7. The method of claim 6 wherein the homogenisation and highly propagating ultrasonic energy act synergistically to transfer the liquid into the solid.

8. A method for filtering a solid comprising

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid;

(ii) filtering the mixture under a vacuum.

9. The method of claim 8 wherein the vacuum and highly propagating ultrasonic energy act synergistically to filter the solid.

10. The method of claim 8 or claim 9 wherein the filtration is selected from the group consisting of reverse osmosis filtration, ultrafiltration, microfiltration, crossflow filtration, metal screens, mesh screens or any combination thereof.

11. The method of any one of claims 1 to 10 wherein the mixture is provided as a pre-mixture of a solid and a liquid.

12. The method of any one of claims 1 to 10 wherein the frequency of the highly propagating ultrasonic energy is about 16 kHz to about 20 kHz.

13. The method of any one of claims 1 to 10 wherein the amplitude of the highly propagating ultrasonic energy is about 0.001 -micron to about 500 microns.

14. The method of any one of claims 1 to 10 wherein the amplitude of the highly propagating ultrasonic energy is between about 0.01 to about 150 microns

15. The method of any one of claims 1 to 10 wherein the amplitude of the highly propagating ultrasonic energy is about 0.01 -micron to about 20 microns.

16. The method of any one of claims 1 to 10 wherein the highly propagating ultrasonic energy is applied at an energy density of between about 0.00001 watt/cm3 to 1000 watt/cm3

17. The method of any one of claims 1 to 10 wherein the highly propagating ultrasonic energy is applied at an energy density of between about 0.0001 watt/cm to about 90 watts/cm3.

18. The method of any one of claims 1 to 10 wherein the highly propagating ultrasonic energy is applied at a frequency between about 16 KHz and about 20 KHz and at an amplitude of between 0.001 -micron to about 500 microns and at an energy density of between about 0.00001 watt/cm3 to about 1000 watts/cm3.

19. The method of any one of claims 1 to 10 wherein the highly propagating ultrasonic energy is applied at a frequency between about 16 KHz and about 20 KHz and an energy density of between about 0.0001 watt/cm3 to about 100 watts/cm3.

20. The method of any one of claims 1 to 10 wherein the highly propagating ultrasonic energy is applied at a frequency between about 16 KHz and about 20 KHz and at an amplitude of between 0.01 -micron to about 20 microns and at an energy density of about 0.0001 watt/cm3 to about 90 watts/cm3.

21. The method of any one of claims 1 to 10 wherein the liquid is an aqueous liquid or non-aqueous liquid.

22. The method of any one of claims 1 to 10 wherein the liquid comprises flavourings, herbs, spices, coatings, preservatives or any combination thereof.

23. The method of any one of claims 1 to 10 wherein the liquid is a food marinate, syrup, sugar solution, protein solution, vegetable or fruit juice or mixtures thereof.

24. The method of any one of claims 1 to 10 wherein the liquid comprises chemical sanitizers, preservatives or enzymes.

25. The method of any one of claim 20 wherein the non-aqueous liquid is an oil or a solvent.

26. The method of claim 24 wherein the solvent is selected from the group consisting of hexane, ethanol, isopropanol, methanol or mixtures thereof.

27. The method of any one of claims 1 to 10 wherein the frequency of the highly propagating ultrasonic energy is the resonant frequency of the solid.

28. The method of any one of claims 1 to 10 wherein the highly propagating ultrasonic energy is applied over a period of time between about 0.001 second to about 24 hours.

29. The method of any one of claims 1 to 10 wherein the temperature of the mixture is between about 2°C and about 99°C.

30. The method of claim 4 or claim 5 wherein the pressure applied to the mixture is between about 0.1 bar and about 5 bar.

31. The method of claim 4 or claim 5 wherein the pressure is between about 1 bar and about 3 bar.

32. A method of enhancing liquid transfer into a solid comprising application of highly propagating ultrasonic energy to a flow stream thereby transferring the liquid into said solid wherein the highly propagating ultrasonic energy has a frequency of greater than about 10kHz and wherein the ultrasonic energy propagates across and through multiple surfaces.

33. The method of claim 32 wherein the highly propagating ultrasonic energy propagates through a surface of a pipe, vessel or container to the solid.

34. The method of claim 32 wherein the highly propagating ultrasonic energy propagates through solid suspended in the liquid.

35. A method of enhancing liquid transfer into a solid present in a flow stream comprising liquid and solid components as the flow stream passes through an apparatus, the method comprises;

(i) attaching a high power transducer to an external surface of the apparatus;

(ii) operating the transducer to emit highly propagating ultrasonic energy, wherein the highly propagating ultrasonic energy propagates across and through multiple surfaces and is applied to the solid and the highly propagating ultrasonic energy has a frequency of between about 16 kHz to about 500 kHz; and wherein the application of highly propagating ultrasonic energy to said solid thereby transfers the liquid into said solid.

36. The method of claim 35 wherein the highly propagating ultrasonic energy is emitted via a sonotrode.

37. The method of claim 36 wherein at least a portion of the sonotrode is immersed in a coupling liquid which is in contact with at least a portion of the apparatus.

38. The method of claim 36 or claim 37 wherein the sonotrode vibrates at a frequency of between about 16 kHz and about 500 kHz.

39. The method of claim 38 wherein the sonotrode vibrates at a frequency of between about 16 kHz and about 20 kHz.

40. The method of claim 35 wherein the transducer includes a vibration direction conversion member.

41. The method of any one of claims 35 wherein the frequency of the highly propagating ultrasonic energy is between about 16 kHz and about 40 kHz.

42. The method of any one of claims 35 wherein the frequency of the highly propagating ultrasonic energy is between about 16 kHz and about 20 kHz

43. The method of any one of claims 35 to 42 wherein the temperature of the liquid is between about 3°C and about 90°C.

44. The method of any one of claims 35 to 43 wherein the flow stream comprises between about 1 to about 80% solids.

45. The method of any one of claims 35 to 43 further comprising the application of at least one of heat, mixing, homogenisation, soaking, pressure or vacuum or any combination thereof and wherein the highly propagating ultrasonic energy acts synergistically with the heat, mixing, homogenisation, soaking, pressure or vacuum to enhance liquid transfer into the solid.

46. A method for transferring liquid into a solid comprising applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid.

47. A method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) applying heat to the mixture.

48. A method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) applying pressure to the mixture.

49. A method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) homogenising the mixture.

50. A method for filtering a solid comprising

(i) applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid;

(ii) filtering the mixture under a vacuum.

51. A method of enhancing liquid transfer into a solid comprising application of highly propagating ultrasonic energy to a flow stream thereby transferring the liquid into said solid wherein the ultrasonic energy propagates across and through multiple surfaces.

52. A method of enhancing liquid transfer into a solid present in a flow stream comprising liquid and solid components as the flow stream passes through an apparatus, the method comprises;

(i) attaching a high power transducer to an external surface of the apparatus; (ii) operating the transducer to emit highly propagating ultrasonic energy, wherein the highly propagating ultrasonic energy propagates across and through multiple surfaces and is applied to the solid and wherein the application of highly propagating ultrasonic energy to said solid thereby transfers the liquid into said solid.

53. The method of any one claims 46 to 52 wherein the frequency of the highly propagating ultrasonic energy is between about 10 KHz and about 2000 KHz or between about 10 KHz and about 1500 KHz, or between about 10 KHz and about 1000 KHz, or between about 10 KHz and about 750 KHz, or between about 10 KHz and about 400 KHz, or between about 10 KHz and about 250 KHz, or between about 10 KHz and about 125 KHz, or between about 10 KHz and about 100 KHz, or between about 10 KHz and about 60 KHz, or between about 10 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 10 KHz and about 20 KHz, or between about 16 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 16 kHz and about 26kHz or between about 19 KHz and about 28 KHz, or between about 16 KHz and about 22 KHz, or between about 16 KHz and about 20.0KHz.

Description:
Mass Transfer

Cross-Reference to Related Application

This application claims the benefit of Australian Provisional Patent Application No. 2009900111 filed 13 January 2009 which is incorporated herein by reference in its entirety.

Technical Field

The present invention relates to apparatus and methods for applying high power ultrasonic energy to enhance liquid mass transfer or hydration of a solid such as food, agricultural or non-food products.

Background

Presently there are a limited number of ways of facilitating liquid mass transfer or hydration of solid materials, such as food, agricultural or non-food products. Equipment and methods used in industry comprise technologies such as mixers in tanks, large tanks, heat or a combination thereof to facilitate mass transfer of liquids into a solid or hydration of a solid. A problem with conventional equipment and methods is that a long time period is required for liquid transfer or hydration to occur. This negatively impacts production rates and in cases where elevated temperatures are used, food quality is reduced due to exposure to elevated temperatures for extended periods. Other problems of conventional equipment and apparatus for liquid mass transfer or hydration include high power and high liquid consumption in addition to non-uniform liquid transfer which negatively impacts product quality.

A conventional ultrasonic bath produces ultrasonic energy in the form of a standing wave such that when a solid is placed in the bath the pattern of mass transfer or hydration shows alternating partially hydrated zones or zones which have received mass and other zones in which have not been affected. In order to achieve a greater effect in hydration or mass transfer the solid must be moved relative to the standing wave which can be impractical for large volumes of solid, large flow streams or large batch volumes. Liquid transfer using an ultrasonic bath while demonstrating some potential use in the cleaning of smaller articles, is ineffective in terms of liquid mass transfer/hydration.

Furthermore, conventional ultrasonic baths produce energy waves that dissipate very quickly with distance and do not propagate through high density or high percentage solid products.

Accordingly there exists a need in the art for improved methods for liquid transfer into a product including methods of enhancing hydration of a product.

Summary

In a first aspect there is provided a method for transferring liquid into a solid comprising applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said mixture thereby transferring the liquid into said solid.

In a second aspect there is provided a method for transferring liquid into a solid comprising;

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said mixture thereby transferring the liquid into said solid and;

(ii) applying heat to the mixture.

In one embodiment the heat and highly propagating ultrasonic energy act synergistically to transfer the liquid into the solid.

In a third aspect there is provided a method for transferring liquid into a solid comprising;

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;.

(ii) applying pressure to the mixture

In one embodiment the pressure and highly propagating ultrasonic energy act synergistically to transfer the liquid into the solid.

In a fourth aspect there is provided a method for transferring liquid into a solid comprising; (i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) homogenising the mixture.

In one embodiment the homogenisation and highly propagating ultrasonic energy act synergistically to transfer the liquid into the solid.

In a fifth aspect there is provided a method for filtering a solid comprising

(i) applying highly propagating ultrasonic energy at frequency of between about 16 kHz to about 40 kHz to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) filtering the mixture under a vacuum.

In one embodiment the vacuum and highly propagating ultrasonic energy act synergistically to filter the solid.

In one embodiment the filtering may be reverse osmosis filtration, ultrafiltration, microfiltration, crossflow filtration, metal screens, mesh screens or any combination thereof.

The mixture may be provided as a pre-mixture of a solid and a liquid.

The liquid may be an aqueous liquid or non-aqueous liquid.

The liquid may comprise flavourings, herbs, spices, coatings, preservatives. The liquid may be a food marinate. The liquid may be a syrup, sugar solution, protein solution, vegetable or fruit juice or mixtures thereof. The liquid may be a dairy stream. The liquid may comprise chemical sanitizers, preservatives or enzymes.

The non-aqueous liquid may be an oil or a solvent. The solvent may be selected from the group comprising hexane, ethanol, isopropanol, methanol or mixtures thereof.

In preferred embodiments the frequency of the highly propagating ultrasonic energy is the resonant frequency of the solid.

The amplitude of the highly propagating ultrasonic energy may be between about 0.01 to about 150 microns. The highly propagating ultrasonic energy may be applied over a period of time between about 0.001 second to about 24 hours.

The temperature of the mixture may be between about 2°C and about 99°C. The pressure applied to the mixture may be between about 0.1 bar and about 10 bar. In a preferred embodiment the pressure is between about 1 bar and about 3 bar.

In a sixth aspect there is provided a method of enhancing liquid transfer into a solid comprising application of highly propagating ultrasonic energy to a flow stream thereby transferring the liquid into said solid wherein the highly propagating ultrasonic energy has a frequency of greater than about 10kHz and wherein the ultrasonic energy propagates across and through multiple surfaces. The highly propagating ultrasonic energy may be propagate through a surface of a pipe, vessel or container to the mixture. The highly propagating ultrasonic energy may propagate through solid substrates, particles or materials such as a seeds, skins, fibres, proteins, husks, or grains suspended in the liquid.

In a seventh aspect there is provided a method of enhancing a thermal liquid transfer through packaging materials, into liquid and/or solid flow streams comprising liquid and solid components or to plant equipment. The method includes attaching a high power transducer (frequency about 16kHz to about 50OkHz) to the outside of the equipment. In use the transducer emits highly propagating ultrasonic energy (radial waves) across and through multiple surfaces. In an embodiment a sonotrode may be immersed into a coupling liquid. The sonotrode is characterised in that it vibrates at a frequency of between about 16 kHz and about 500 kHz. The sonotrode is characterised in that it emits a radial energy wave (highly propagating ultrasonic energy) relative to the sonotrode and the radial energy travels through the material or flow stream and enhances liquid mass transfer or hydration of liquids into food, agricultural or non-food products.

The transducer may include a vibration direction conversion member.

In a further embodiment the energy wave is a high distance propagating wave through mediums of about 1 to about 80% solids content.

In a still further embodiment the energy wave is a highly penetrating wave across and through the surface and into liquid streams/solid structures.

In a yet still further embodiment the equipment used with the ultrasound is a pipe or a tank/vessel used in the food, agricultural, non-food industry but not limited to these.

In a preferred embodiment the highly propagating ultrasonic energy is synergistically combined with other technologies used for hydration such as steeping tanks, malting tanks, mixers, homogenizers, pressure or vacuum tanks, heat or any combination thereof.

In an eighth aspect there is provided a method for transferring liquid into a solid comprising applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid.

In a ninth aspect there is provided a method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) applying heat to the mixture.

In a tenth aspect there is provided a method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) applying pressure to the mixture.

In an eleventh aspect there is provided a method for transferring liquid into a solid comprising

(i) applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid solid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid and;

(ii) homogenising the mixture.

In a twelfth aspect there is provided a method for filtering a solid comprising

(i) applying highly propagating ultrasonic energy to a mixture comprising a solid and a liquid wherein the highly propagating ultrasonic energy is uniformly distributed throughout said solid thereby transferring the liquid into said solid;

(ii) filtering the mixture under a vacuum.

In a thirteenth aspect there is provided a method of enhancing liquid transfer into a solid comprising application of highly propagating ultrasonic energy to a flow stream thereby transferring the liquid into said solid wherein the ultrasonic energy propagates across and through multiple surfaces. In a fourteenth aspect there is provided a method of enhancing liquid transfer into a solid present in a flow stream comprising liquid and solid components as the flow stream passes through an apparatus, the method comprises;

(i) attaching a high power transducer to an external surface of the apparatus;

(ii) operating the transducer to emit highly propagating ultrasonic energy, wherein the highly propagating ultrasonic energy propagates across and through multiple surfaces and is applied to the solid and wherein the application of highly propagating ultrasonic energy to said solid thereby transfers the liquid into said solid.

In one embodiment of any one of the eighth to fourteenth aspects the frequency of the highly propagating ultrasonic energy may be between about 10 KHz and about 2000 KHz or between about 10 KHz and about 1500 KHz, or between about 10 KHz and about 1000 KHz, or between about 10 KHz and about 750 KHz, or between about 10 KHz and about 400 KHz, or between about 10 KHz and about 250 KHz, or between about 10 KHz and about 125 KHz, or between about 10 KHz and about 100 KHz, or between about 10 KHz and about 60 KHz, or between about 10 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 10 KHz and about 20 KHz, or between about 16 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 16 kHz and about 26kHz or between about 19 KHz and about 28 KHz, or between about 16 KHz and about 22 KHz, or between about 16 KHz and about 20.0KHz.

Brief Description of the Drawings

Figure 1 is a schematic illustration of a highly propagating ultrasonic energy system for enhancing liquid mass transfer and hydration of a product wherein a sonotrode is in direct contact with the product.

Figure 2 is a schematic illustration of a highly propagating ultrasonic energy system for enhancing liquid mass transfer and hydration of a product wherein highly propagating ultrasonic energy is applied indirectly to the product.

Figure 3 is a schematic illustration of a highly propagating ultrasonic energy system for enhancing liquid mass transfer and hydration of a product wherein highly propagating ultrasonic energy is indirectly transferred to the product via a fluid. Figure 4 is a schematic illustration of a system for filtering a product. The system comprises a means for enhancing liquid mass transfer and hydration of a product by application of highly propagating ultrasonic energy and a filter means to increase flux rate/capacity through a filter and improved filtration efficiency.

Figure 5A is a schematic illustration of a system for homogenising a product. The system comprises a means for enhancing liquid mass transfer and hydration of a product by application of highly propagating ultrasonic energy before a conventional homogeniser means.

Figure 5B is a schematic schematic illustration of a highly propagating ultrasonic energy homogeniser apparatus for enhancing liquid mass transfer and hydration.

Figure 6 is a flow chart of a process for production of dry dairy or soy protein.

Figure 7 is a flow chart of a process for extraction of palm and olive oil.

Figure 8 is a flow chart of a process for producing fruit extracts.

Figure 9 schematic illustration of an ultrasound system wherein the ultrasound equipment is installed in an open or closed tank and the energy is directly transferred into the product from the sonotrode.

Definitions

The terms "highly propagating radial energy" and "highly propagating ultrasonic energy" are used interchangeably to refer to energy emitted substantially orthogonal to the axial direction of the sonotrode or transducer.

The term "comprising" means including principally, but not necessarily solely. Furthermore, variations of the word "comprising", such as "comprise" and "comprises", have correspondingly varied meanings.

As used in this application, the singular form "a", "an" and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a surface" also includes a plurality of surfaces.

As used herein, the term "synergistic" refers to a greater than additive effect that is produced by a combination of two entities. A synergistic effect exceeds that which would be achieved by combining the effect of each entity taken alone. As used herein, the term "solid" refers to a substance having a shape and volume and which is neither liquid nor gaseous. A solid may therefore be porous or permeable.

As used herein the terms "mass transfer" and "liquid mass transfer" refer to the transfer of a liquid into a solid. The term 'hydration' is used to refer to the transfer of water into a solid.

As used herein "enhanced" refers to an effect that is greater than the same effect without the application of highly propagating ultrasonic energy.

Detailed Description

The skilled person will understand that the figures and examples provided herein are to exemplify, and not to limit the invention and its various embodiments.

Conventional ultrasonic apparatus may be used to enhance mass transfer or hydrate a product but suffer from a number of disadvantages. For example, the use of conventional ultrasonic energy produced in a conventional apparatus creates standing waves in the product filling the apparatus so that the product will show zones of enhanced mass transfer or hydration in areas not bounded by the standing waves and zones where mass transfer or hydration is enhanced in the regions bounded by the standing waves.

As mentioned above conventional ultrasonic cleaning bath technology/transducers are based on the formation of standing wave technology. Standing waves do not penetrate into products as the energy levels are very low. Similarly standing waves do not enhance liquid mass transfer or hydration. Furthermore the formation of standing waves results in areas exposed to the standing waves and areas that are not exposed, typically giving a 50% dead zone. Thus, in a solid product such as a dry food product, the result may be that only 50% of the product has enhanced hydration.

Further, conventional systems produce energy waves that dissipate very quickly with distance and do not affect the liquid mass transfer properties of a fluid and little if any possibility of enhancing hydration of a solid. For example, a conventional sonotrode experiences a drop in energy of 95% over 10mm from the sonotrode in a product with 30% solid material, with negligible penetration into surrounding material. The treated zone from these waves produced is not effective across a large volume of product that is cavitation occurs in some areas and not in others.

In accordance with the present invention methods for applying highly propagating ultrasonic energy to enhance mass transfer and enhance hydration of a solid are provided. The methods of the invention generally comprise the application of highly propagating ultrasonic energy to a product to enhance the hydration of a solid or to enhance the mass transfer into solid. The solids may be solid or semi solid food or non-food products including agricultural products. The solids may also be products formulated for human or animal consumption

The use of highly propagating radial energy waves has substantial improvements over existing ultrasonic technology and sonotrode systems that until now has not been exploited, for example:

1. significantly enhanced working/travel distance of energy waves

2. high energy to change molecular structure

3. ability to penetrate through solid boundaries and surfaces

4. uniform treatment

5. enhance convective liquid transfer

Highly propagating ultrasonic energy

A sonotrode generates ultrasonic energy typically when an alternating voltage is applied across a ceramic or piezoelectric crystalline material (PZT). The alternating voltage is applied at a desired oscillation frequency to induce movement of the PZT. The PZT transducer is mechanically coupled to the horn means which amplifies the motion of the PZT. The horn means includes a tip portion, referred to herein as a sonotrode. The assembly of the PZT horn means including the tip portion may also be referred to herein as the sonotrode. Highly propagating ultrasonic energy or HPU includes ultrasonic energy that is emitted substantially orthogonal to the axial direction of a sonotrode. Such energy propagates through a fluid medium, typically water or a gas and over a large distance from the sonotrode and is not limited to the areas immediately surrounding the sonotrode. After propagating through the medium the highly propagating ultrasonic energy may be applied over a surface and to penetrate into said surface.

Highly propagating ultrasonic energy waves are able to propagate across through a liquid up to a distance of at least 50cm to about 300cm, or about 100cm to about 300cm or about 150cm to about 300cm or about 200cm to about 300cm to a surface of a solid. Highly propagating ultrasonic energy propagates substantially uniformly across volumes leaving and are able to penetrate up to up to a depth of about 0.0001-lmm, or about l-20mm, or up to a depth of about 2-20mm or up to a depth of about 5-20mm or up to about 5- 15mm or up to about 7- 10mm into substantially solid, porous or colloidal components of a product.

In one embodiment of the present invention a combination of the high power, low frequency, long wavelength and sonotrode shape/design allows for the above effects to take place. In contrast, ultrasonic energy emitted from conventional ultrasonic cleaners has limited propagation distance from the emitting surface with a drop in energy of 90+ % at a distance of 100 cm and are not uniform in their volume area or volume of the treated flow stream, and do not have the ability to penetrate into solid, porous or colloidal components of a product.

In another embodiment, the sonotrode may be arranged such that the highly propagating ultrasonic energy generated is able to propagate through a viscous liquid up to a distance of about 50cm to about 300cm, or about 100cm to about 300cm or about 150cm to about 300cm or about 200cm to about 300cm to the inner surface of a flow cell, conduit, vessel containing the fluid, transmit uniformly throughout the whole volume leaving no single space/zone untouched from the wave energy. In addition, the highly propagating radial waves are able to penetrate up to about 5-20mm or up to about 5- 15mm or up to about 7- 10mm or into solid, porous or colloidal components of a product suspended in the flow stream or material.

In yet another embodiment, the highly propagating ultrasonic energy is emitted substantially at a right angle from the surface of a sonotrode with high energy. In this context high energy refers to a less than about 20% drop in energy and production of shear forces resulting from collapsing cavitation bubbles at a distance of about 100 to about 300cm from the emitting sonotrode. Furthermore, in this context high energy refers to the ability of the highly propagating ultrasonic energy to propagate into solid, porous or colloidal components of a product and create cavitation internally up to a depth of about 0.0001-lmm, or about 1 -20mm, or up to a depth of about 2-20mm or up to a depth of about 5-20mm or up to about 5-15mm or up to about 7- 10mm.

While not being limited by theory it is generally held that highly propagating ultrasonic energy enhances liquid mass transfer and enhanced hydration via generating cavitation. Cavitation comprises the repeated formation and implosion of microscopic bubbles. The implosion generates high-pressure shock waves and high temperatures near the site of the implosion. As a result, the energy waves from collapsing cavitation bubbles causes the fluid to accelerate at very high speed and enhance the penetration into a solid substrate. The enhanced liquid mass transfer and penetration into the solid substrate can occur without effecting the physical surface of the outer boundary layer.

In one embodiment the ultrasonic emitting assembly or ultrasonic generator generates highly propagating ultrasonic energy at frequencies between about 10 KHz and about 2000 KHz or between about 10 KHz and about 1500 KHz, or between about 10 KHz and about 1000 KHz, or between about 10 KHz and about 750 KHz, or between about 10 KHz and about 400 KHz, or between about 10 KHz and about 250 KHz, or between about 10 KHz and about 125 KHz, or between about 10 KHz and about 100 KHz, or between about 10 KHz and about 60 KHz, or between about 10 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 10 KHz and about 20 KHz, or between about 16 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 16 kHz and about 26kHz or between about 19 KHz and about 28 KHz, or between about 16 KHz and about 22 KHz, or between about 16 KHz and about 20 KHz.

For example the amplitude of the highly propagating ultrasonic energy is between about 0.001 to about 500 microns, preferably between about 0.01 to about 40 microns amplitude, even more preferably between about 1 to about 10 microns.

For example the energy density of the highly propagating ultrasonic energy is between about of 0.00001 watt/cm 3 to 1000 watt/cm 3 , between about 0.0001 watt/cm 3 to about 100 watts/cm 3 .

For example highly propagating ultrasonic energy applied to a solid for enhanced mass transfer and hydration between about 0.00001 W/cm 3 to about 500W/cm 3 and amplitudes of between about 0.001 micron and about 150 microns. The highly propagating ultrasonic energy may be applied at between about 0.0001 W/cm 3 to about 400W/cm 3 or between about 0.001 W/cm 3 to about 350W/cm 3 , or between about 0.01 W/cm 3 to about 300W/cm 3 , or between about 0.1 W/cm 3 to about 50W/cm 3 . The amplitude may be between about 0.01 microns to about 140 microns, or between 0.1 microns to about 100 microns, or between about 1 microns to about 50 microns, between about 1 microns to about 30 microns. In a further embodiment highly propagating ultrasonic energy is applied to a solid for enhanced mass transfer and hydration at about 0.000 lW/cm 2 to about lOOOW/cm 2 and amplitudes of about 0.1 micron to about 30 microns. The highly propagating ultrasonic energy may be applied at between about 0.0001 W/cm 2 to about lOOOw/cm 3 , O.OOlW/cm 2 to about 500W/cm 2 or between about 0.01W/cm 2 to about 200W/cm 2 , or between about 0.1 W/cm 2 to about lOOW/cm 2 , or between about l.OW/cm 2 to about 50W/cm 2 .

The highly propagating ultrasonic energy may be applied at a frequency between about 16 KHz and about 40 KHz, or between about 16 KHz and about 20 KHz and at an energy density of between about 0.00001 watt/cm 3 to 1000 watt/cm 3 or between about 0.0001 watt/cm 3 to about 100 watts/cm 3 . In a preferred embodiment the highly propagating ultrasonic energy may be applied at a frequency between about 16 KHz and about 20 KHz and at an energy density of about 0.0001 watt/cm 3 to about 50 watt/cm 3 .

In another embodiment the highly propagating ultrasonic energy may be applied at a frequency between about 16 KHz and about 40 KHz, or between about 16 KHz and about 20 KHz and at an amplitude of between 0.001 -microns to about 500 microns. In a preferred embodiment the highly propagating ultrasonic energy may be applied at a frequency between about 16 KHz and about 20 KHz and at an amplitude of between 0.01-micron to about 20 microns.

In a further embodiment the highly propagating ultrasonic energy may be applied at a frequency between about 16 KHz and about 40 KHz, or between about 16 KHz and about 20 KHz and at an amplitude of between 0.001 -microns to about 500 microns and at an energy density of between about 0.00001 watt/cm 3 to 1000 watt/cm 3 or between about 0.0001 watt/cm 3 to about 100 watts/cm 3 . In a preferred embodiment the highly propagating ultrasonic energy may be applied at a frequency between about 16 KHz and about 20 KHz and at an amplitude of between 0.01-micron to about 20 microns and at an energy density of about 0.0001 watt/cm 3 to about 90 watt/cm 3 .

In another embodiment the highly propagating ultrasonic energy is applied over a period of time from about 0.001 second to about 72 hours, or from about 0.001 second to about 24 hours, or from about 10 seconds to about 10 hours, or from about 1 second to about 1 hour, or from about 1 second to about 30 minutes, or from about 1 second to about 20 minutes, or from about 1 second to about 10 minutes, or from about 1 second to about 2 minutes or from about 1 second to about 1 minute. Enhanced mass transfer and hydration

Highly propagating ultrasonic energy may be used to increase liquid transfer of a fluid into a solid. Typically such a method includes the application of highly propagating waves across and through multiple surfaces. For example a solid may be immersed into a coupling liquid which is in contact with an ultrasonic sonotrode.

Increased performance of enhanced liquid mass transfer or hydration of liquids into solids such as food, agricultural or non-food products is typically achieved by using an automatic frequency scanning system for different types of equipment. For example, the type of surface (shape, dimensions, type of material), thickness or number of surfaces and type of contamination will determine the resonance frequency of that equipment. The ultrasonic resonance frequency is the frequency at which the ultrasonic unit will deliver the greatest energy efficiency.

The resonance frequency of a solid is the frequency of the solid at which it oscillates at larger amplitude and power/efficiency compared to other frequencies. At the resonant frequency periodic driving forces (such as the application of highly propagating ultrasonic energy) can produce large amplitude oscillations. While the application of highly propagating ultrasonic energy to a solid enhances mass transfer and hydration, if the frequency of the highly propagating ultrasonic energy is matched to the resonance frequency of the solid mass transfer and hydration will be more efficient than at other frequencies.

The methods described herein are particularly suited for use with an ultrasonic system, which locks onto the resonance frequency of a specific type of equipment and then re-scans for the new resonance frequency every 0.001 second throughout the treatment process. Without resonance frequency tracking a variation as little as 1 OHz from the resonance frequency would result in a drop in energy efficiency in the order of 10 — 40%. This would have a significant reduced effect on the enhanced hydration/liquid mass transfer efficiency.

By way of example, the resonance frequency of water/oats is 20,450 Hz where as dairy proteins will have a resonance frequency of 20,260 Hz, whey protein will have a resonance frequency of 20,218Hz, water and barley grain will have a resonance frequency of 20,320Hz, rice and water will have a resonance frequency of 20,308Hz. Conventional devices using transducers welded/bolted to the outside of vessels/chambers/tubes are not designed with an automatic resonance frequency tracking system for specific types of organic equipments so equipments could not be processed at the correct resonance frequency and maximum power efficiency.

In one embodiment the hydration of grains may be enhanced by application of highly propagating ultrasonic energy to a mixture of grain and liquid. Typically the liquid is water.

In one example hydration of oats by water is enhanced when an oats/water mixture is exposed to highly propagating ultrasonic energy of >1 micron amplitude at a power of >0.1 watt/cm 3 . Conventional ultrasonic baths, the use of sonotrodes suitable for liquid immersion or conventional hydration processes of soaking typically require about 26 hours to hydrate oats (see for example Table 1.0, Example 1). However, the application of highly propagating ultrasonic energy enhances the hydration of oats and may decrease the time to hydrate the oats. In preferred embodiments the time to hydrate oats may be between about 10 to about 20 hours, or between about 12 to about 18 hours, or between about 13 to about 17 hours, or between about 14 to about 16 hours or 1 to 15 hours or 1 to 5 hours or 0.5 to 1 hour or 0.1 to 1 hour or lsec to lhour or 0.1 sec to 1 hour.

The application of highly propagating ultrasonic energy enhances mass transfer at a variety of temperatures. The temperature may be between about I 0 C and about 15O 0 C, or between about between about I 0 C and about 125 0 C, or between about TC and about 100°C, or between about 1°C and about 75 0 C, or between about I 0 C and about 5O 0 C, or between about 2 0 C and about 25 0 C, or between about 3 0 C and about 2O 0 C, or between about 4 0 C and about 15 0 C, or between about 5 0 C and about 1O 0 C.

The application of highly propagating ultrasonic energy enhances mass transfer at a variety of pressures. The pressure may be between about 0.1 bar and about 10 bar or between about 0.1 bar and about 5 bar or between about 1 bar and about 3 bar.

Synergistic effect of highly propagating ultrasonic energy and other technologies or agents for enhancing liquid mass transfer and hydration.

As disclosed herein the application of highly propagating ultrasonic energy to a solid results in enhanced liquid mass transfer and hydration. Surprisingly, the application of highly propagating ultrasonic energy to a solid together with conventional methods of mass transfer results in enhanced liquid mass transfer and hydration of a solid than would be expected merely from the additive effects of conventional methods and the application of highly propagating ultrasonic energy. That is, there is a synergistic effect between the application of highly propagating ultrasonic energy to a solid and the use of conventional methods of enhancing mass transfer and hydration. This synergism results in enhanced liquid mass transfer and hydration methods.

The conventional methods of enhancing mass transfer and hydration include homogenisation, pressure, heat and the application of a vacuum.

The highly propagating ultrasonic energy is preferably applied to the reaction mixture at an average specific energy between 1x10 7 kWh and IxIO "1 kWh ultrasonic energy per liter reaction mixture, more preferably between IxIO "4 kWh and IxIO '2 kWh ultrasonic energy per liter reaction mixture. Low frequency/high intensity ultrasound in combination with mild heat (0°C - 90°C) may also be used to enhance liquid mass transfer and hydration.

With reference to example 13, the application of highly propagating ultrasonic energy to a mixture of 4 parts hexane to 1 part corn germ increases the level of liquid mass transfer into the corn germ compared to conventional stirring. When the mixture is exposed to highly propagating ultrasonic energy of between about 500 watts and about 900 watts at a frequency of 2OkHz at temperatures of 5, 10 and 2O 0 C.

At 5 0 C application of highly propagating ultrasonic energy at 500 watts or 900 watts together with stirring results in 55% or 78% liquid to solid transfer respectively, application of highly propagating ultrasonic energy only at 500 watts or 900 watts results in 49% or 58% liquid to solid transfer respectively while stirring for 30seconds results in 5% liquid to solid transfer.

When the temperature is increased to 1O 0 C application of highly propagating ultrasonic energy at 500 watts or 900 watts together with stirring results in 64% or 87% liquid to solid transfer respectively, application of highly propagating ultrasonic energy only at 500 watts or 900 watts results in 55% or 66% liquid to solid transfer respectively while stirring for 30seconds results in 7% liquid to solid transfer.

When the temperature is further increased to 2O 0 C application of highly propagating ultrasonic energy at 500 watts or 900 watts together with stirring results in 74% or 95% liquid to solid transfer respectively, ultrasound only at 500 watts and 900 watts results in 64% and 79% liquid to solid transfer respectively while stirring for 30seconds results in 9% liquid to solid transfer. At 25 0 C application of highly propagating ultrasonic energy at 500 watts or 900 watts together with stirring results in 79% or 98% liquid to solid transfer respectively, ultrasound only at 500 watts and 900 watts results in 69% and 85% liquid to solid transfer respectively while stirring for 30seconds results in 15% liquid to solid transfer.

Accordingly the synergistic effect between ultrasonic energy and heat greatly enhances the liquid to solid mass transfer. In preferred embodiments the level of liquid to solid transfer is about 40% to about 99%, or between about 50% to about 99%, or between about 60% to about 99%, or between about 70% to about 99%, or between about 80% to about 99%.

In a further aspect low frequency/high intensity highly propagating ultrasonic energy is applied to a solid in combination with pressure. Typically the pressure is between about 0.5 to 10 bar. In some embodiments the pressure is between about 1 bar and about 3 bar. The combination of pressure and low frequency/high intensity highly propagating ultrasonic energy synergistically enhances mass transfer of liquid into a solid. This synergistic effect between ultrasonic energy and pressure greatly enhances the coupling and impedance matching of the ultrasonic waves to the medium particularly when the fluid contains high solids content. The improved coupling of the waves to the solid enhances liquid mass transfer and hydration. The preferred equipment design for this method utilises radial sonotrodes, which emit high-energy ultrasonic waves. However, other sonotrodes could be used such as high amplitude focused sonotrodes, which produce high concentration of localized cavitation bubbles around the sonotrode surface.

For example, the application of either highly propagating ultrasonic energy alone or pressure alone increases the hydration level of a grain in a nmixture of grain and water. The additive effects highly propagating ultrasonic energy and pressure would each be expected to result in an increase in hydration level of the grain. However, the highly propagating ultrasonic energy and pressure may act synergistically to produce a increase in hydration level, than would be expected from the additive effects highly propagating ultrasonic energy and pressure.

In some embodiments the hydration level of a grain may be increased by the application of highly propagating ultrasonic energy and pressure to between about 20% to about 50%, or between about 25% to about 45%, or between about 30% to about 40%. The pressure may be between about 0.1 bar to about 10 bar, or about 0.5 bar to about 5 bar, or about 1 bar to about 3 bar.

In another aspect highly propagating ultrasonic energy is applied to a solid in conjunction with a vacuum to enhance liquid mass transfer, particularly to increase filtration rates.

The filtration rate of a solid through a vacuum filter is increased by the application of highly propagating ultrasonic energy. In preferred embodiments the filtration rate may be increased by at least about 0.1 litres/min, or by at least about 0.5 litres/min, or by about at least 1.0 litres/min, or by about at least 2.0 litres/min, or by about at least 3.0 litres/min, or by about at least 4.0 litres/min, or by about at least 5.0 litres/min.

In a further aspect highly propagating ultrasonic energy is applied to a solid in conjunction with conventional homogenisation or mixing to synergistically enhance liquid mass transfer or hydration of liquids into food, agricultural or non-food products.

The application of highly propagating ultrasonic energy to a mixture of a solid such as soya protein powder in a liquid such as orange juice is increases the hydration level of the solid compared to the hydration level after homogenization alone.

In preferred embodiments the hydration level of a solid may be increased by the application of highly propagating ultrasonic in conjunction with conventional homogenisation or mixing to between about 40% to about 99%, or between about 45% to about 99%, or between about 50% to about 99%.

Products

The methods of described herein may be applied to a variety of solids such as food products, grains, hydrocolloids, dairy products, soy proteins, vegetable materials, agricultural products or non-food products.

The grains may be selected from the group comprising oats, barley, wheat, corn, maize, rye and rice. The grains may also be pulses including chickpea, faba/broad bean, field pea, lentil, lupin, vetch, mungbean, azuki bean, soya bean, navy bean, cowpea and pigeon pea.

The hydrocolloid materials may be selected from the group comprising gelatin, starch, xanthan gum, carrageenan, pectin, gum arabic, guar gum, alginates, seaweed powder or combinations of such hydrocolloids. The soya protein may be a soya protein isolate.

The dairy products may be selected from the group comprising whey protein, skimmed milk powder, low fat milk powder, whole fat milk powder, yogurt, butter, margarine and caseinates.

The vegetable materials may include pulp, pomace, fibre, skins from vegetables selected from the group comprising carrot, tomato, onion, garlic, cabbage, broccoli, cauliflower, sweet potato, potato, peas, beans, celery, herbs, pumpkin, capsicum, mushrooms or combinations of, fruit based materials (pulp, pomace, fibre, skins) such as apples, oranges, grapes, apricots, pears, strawberry, raspberry, blueberry, blackberry, lemons, limes, grapefruit, rhubarb, plums, cherries, kiwi fruit, pomegranate, banana, figs, ginger, or combinations thereof, oil seeds such as palm fruit, canola, soya beans, olives, sunflower, coconut, cocoa beans, coffee beans, ground cocoa, ground coffee, powder chocolate and coffee, tea leaf and ground tea, green tea, herbal tea (peppermint, chamomile, rose hip,).

The food product may be selected from the group comprising wheat flour, sugar, confectionery products, bread, dough based materials, bakery products, cakes, snack foods such as pretzels, fried or baked or microwaved potato chips, crisps, snacks or chips, crisps, snacks comprising fruits or vegetables or combinations thereof, breakfast cereal products such as corn flakes, rice flakes or bubbles, oat flakes, muesli, bran flakes, or combinations of or muesli bars, cereal bars, extruded cereal products, dried fruit or dried fruits in combination with cereal products, cooked or none cooked meats such as beef, lamb, chicken, turkey, pork, mutton, deer, ham, or combinations of, seafood and fish such as salmon, tuna, sardines, crab, cod, snapper, trout, mackerel, perch, squid, oysters, scallops, crayfish, lobster, hops, yeast, malted barley, pickled food products, egg powder or products containing egg, salt, ground herbs and spices, products contained in packaged/canned/bottled soups, or products contained in packaged/canned/bottled sauces or canned/packaged/bottled fruit or vegetable products or canned/packaged/bottled beverage products or any combination of the above in the manufacture of any food or beverage product.

The agricultural product may be selected from the group comprising agricultural feedstock material for example for fermenting and making ethanol, or agricultural feedstock material for making biodiesel fuel, sugar cane and sugar beet.

The non-food products may include clay, clay-based materials, paper and timber based pulps, mineral powders and mineral mining ores, plastic materials, foam materials, materials used in the manufacture of pharmaceutical products or any inorganic, organic, mineral material including mineral particles such as those found in mining slurry or gypsum slurry.

Apparatus

An example of an apparatus for enhancing the liquid mass transfer and hydration of a solid by the application of highly propagating ultrasonic energy to the solid is described with reference to Figure 1 where a solid in a mixture with a liquid enters a flow cell 10 at A and exits the flow cell at B. A sonotrode 14 applies highly propagating ultrasonic energy directly to the solid while in the flow cell. A highly propagating ultrasonic energy generator 18 is connected to a transducer 22 which is further connected via a booster means 26 to the sonotrode 14.

Another embodiment is described with reference to Figure 2 which illustrates a highly propagating ultrasonic energy apparatus wherein a highly propagating ultrasonic energy generator 18 is connected to a transducer 22 which is further connected to a booster means 26. The booster means 26 is in contact with and may be mounted to a flow cell 10 enabling the flow cell 10 to indirectly apply highly propagating ultrasonic energy to the solid which enters the flow cell 10 at A and exits at B.

Another embodiment is described with reference to Figure 3 which illustrates a highly propagating ultrasonic energy apparatus wherein the highly propagating ultrasonic energy is indirectly transferred into the reaction mixture from the sonotrode 34 via a suitable fluid medium 30 such as water or oil, to the flow cell 10. The solid in a mixture with a liquid passes through A into the flow cell 10 and exits the flow cell 10 through B. A highly propagating ultrasonic energy generator 18 is connected to a transducer 22 which is further connected via a booster means 26 to the sonotrode 14.

A method of filtering a solid is also provided. With reference to Figure 4 the method comprises application of highly propagating ultrasonic energy to a solid while in passage through a flow cell 10 to enhance the mass transfer into the solid. After exiting the flow cell 10 the solid enters a filter means 62. By way of example the flow rate of a slurry of gluten starch slurry through a vacuum filter is increased by the application of highly propagating ultrasonic energy. In particular the application of highly propagating ultrasonic energy increases the filtration rate by approximately 4 litres/min. In one embodiment highly propagating ultrasonic energy may be applied to the filter during filtration.

It will be understood by the skilled addressee that the filter may, as illustrated in Figure 4 be connected to the outflow of the flow cell 10. In another embodiment the filter may have no direct connection to the flow cell and the solid may be stored before being filtered.

The filter may be any filter known in the art including a vacuum filter reverse osmosis filter, a microfilter or and ultrafilter or cross flow steel or polymer membrane filter, ceramic filter, steel screen or polymer screen filter, any filters known in the art which have pore sizes ranging from 1000 microns in size down to 0.0001 microns in size.

Solids used in this method may be products such as gluten starch slurries, dairy protein, vegetable/agricultural oils, soya proteins, grape juice, fruit juices, milk, skimmed milk, whey protein, caseinates, soya protein isolates, soya bean oils, corn oils, cotton oils, canola oils, citrus oils, orange juice, apple juice, lime and grapefruit juice, tomato sauce, juice or pulp, vegetable juices, palm oil, sunflower oil, high fructose corn syrup, maple syrups, honey, sugar syrups, fruit jams, water for beverages, coffee streams, tea streams, chocolate streams.

A method for homogenising a solid is also provided. With reference to Figure 5A highly propagating ultrasonic energy is applied to a solid during passage through a flow cell 10 to enhance the mass transfer of liquid into the solid. After the solid exits the flow cell it is homogenised in an homogeniser 70 which further enhances the mass transfer of liquid into the solid.

It will be understood by the skilled addressee that the homogeniser 70 may as illustrated in Figure 5A be connected to the outflow of the flow cell. In another embodiment the homogeniser 70 may have no direct connection to the flow cell and the solid may be stored before homogenisation.

Also provided is another method of homogenising a solid. With reference to Figure 5B a multi-phase solid such as the two-phase solid illustrated is homogenised by application of highly propagating ultrasonic energy to the solid during its passage through the flow cell 10.

By way of example, the application of highly propagating ultrasonic energy to a mixture of soya protein powder in orange juice resulted in a 38% hydration level of the soya protein compared to a 14% hydration level after homogenization alone. When the mixture was subjected to homogenisation and highly propagating ultrasonic the hydration level of the soya protein was 46%.

Solids used in the homogenisation methods include products such as soy milk, sauces, dairy products, flavour compositions, oil water mixes, oil water hydrocolloid mixes, food products containing fats/oils, sauces, food/beverage products containing starches or hydrocolloids and beverages. Homogenising these products using the methods of the invention provides reduces energy costs, increased production rates and reduced maintenance costs, better product performance and degree of mix/emulsification.

A process for production of dry protein is provided. With reference to Figure 6 highly propagating ultrasonic energy is applied to a protein in a mixture with a liquid to enhance liquid mass transfer into the solid during at least one of protein precipitation, protein mixing and/or homogenising or evaporation of liquid from protein. The protein may then be spray dried.

A process for extraction of palm or olive oil is provided. With reference to Figure 7 highly propagating ultrasonic energy is applied to a solid before and/or after pressing to enhance liquid mass transfer into the solid

A process for producing fruit extracts is provided. With reference to Figure 8 highly propagating ultrasonic energy is applied to a solid during at least one of before counter current extraction or before filtration to enhance liquid mass transfer into the solid.

Figure 9 illustrates a radial sonotrode 41 in a closed container filled with a suitable liquid 44. The highly propagating ultrasonic energy 42 produced by the radial sonotrode 41 penetrate the solid and enhance the mass transfer of liquid 44 into solid 43.

The present invention will now be further described in greater detail by reference to the following specific examples, which should not be construed as in any way limiting the scope of the invention. Examples

Example 1: Comparison of hydration times of oats using conventional methods and highly propagating ultrasonic energy.

The hydration time of oats using conventional methods (stirring slowly in water) and using highly propagating ultrasonic energy to enhance hydration was tested using mixtures of lkg of oats to 2kg of water at 1O 0 C and ambient pressure.

Ultrasonic energy was applied to one sample using a conventional sonotrode (operating at 500 watts and 2OkHz) for 60 seconds together with the conventional hydration process,

Ultrasonic energy was applied to another sample using a conventional ultrasonic cleaning bath (operating at 500 watts and 38kHz) for 60 seconds together with the conventional hydration process.

Highly propagating ultrasonic energy 60 seconds (2OkHz, 500 watts) was applied to another sample for 60 seconds together with the conventional hydration process (oats stirring slowly in water).

A further sample was hydrated only using the conventional hydration process.

The level of hydration of the oats in each sample was measured by weighing out a lOOg portion of the oats before addition to the liquid then placing that sample in an oven at 100 0 C for five hours before re- weighing that sample, the difference in weights indicates the level of hydration of the sample before application of highly propagating ultrasonic energy. At various times during the hydration process a lOOg sample of the oats was weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the sample after application of highly propagating ultrasonic energy. The time taken for the oats to reach maximum hydration was then recorded. These times are indicated in Table 1.

Table 1.0 Com arison of oat h dration times

Table 1.0 clearly shows the greatly increased efficacy of hydration of oats using highly propagating ultrasonic energy to enhance the kinetics of liquid mass transfer or hydration of water into solid food products such as oats.

Example 2: Enhanced liquid mass transfer and hydration after application of highly propagating ultrasonic energy.

The ability of highly propagating ultrasonic energy to enhance mass transfer and hydration was tested.

Highly propagating ultrasonic energy was applied to various mixtures at various temperatures as set out in Table 2. Each mixture contained 0.5kg of a solid and 2kg of a liquid and highly propagating ultrasonic energy was applied for 30 seconds at 500 watts and 2OkHz. The level of mass transfer and hydration of the solid was measured by weighing out a lOOg portion of the solid material before addition to the liquid then placing that sample in an oven at 100 0 C for five hours before re-weighing that sample, the difference in weights indicates the level of hydration of the sample before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the solid is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the sample after application of highly propagating ultrasonic energy. The % increase in hydration due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of solid before and after application of highly propagating ultrasonic energy.

Table 2. Enhanced liquid mass transfer and hydration after application of highly ro a atin ultrasonic ener

Example 3 Comparison of highly propagating ultrasonic energy and mechanical mixing on hydration levels

The ability of highly propagating ultrasonic energy and mechanical mixing to enhance mass transfer and hydration was tested.

Highly propagating ultrasonic energy was applied to various mixtures as set out in Table 3. Each mixture contained 0.5kg of a solid and 2kg of a liquid. The mixtures were contained in a steel vessel and highly propagating ultrasonic energy was applied for 30 seconds at 500 watts and 17-2OkHz. A control test was performed with only mechanical mixing of the mixtures The level of mass transfer and hydration of the solid was measured by weighing out a lOOg portion of the solid material before addition to the liquid then placing that sample in an oven at 100 0 C for five hours before re- weighing that sample, the difference in weights indicates the level of hydration of the sample before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the solid is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the sample after application of highly propagating ultrasonic energy. The % increase in hydration due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of solid before and after application of highly propagating ultrasonic energy.

Table 3: Ultrasound vs. mechanical mixin

Example 4. Highly propagating ultrasonic energy enhances liquid uptake into grains

The ability of highly propagating ultrasonic energy to travel large distances along pipes and tanks to enhance liquid mass transfer or hydration of liquids into food, agricultural or non-food products was tested. Highly propagating ultrasonic energy was applied to a mixture of 50% barley grains in 50% water at various flow rates (indicated in Table 3 below) using a 8,000 watt 2OkHz flow through unit at 15 0 C.

The level of liquid uptake into grain was measured by weighing out a lOOg portion of the grain before addition to the liquid then placing the grain in an oven at 100 0 C for five hours before re- weighing that grain, the difference in weights indicates the level of hydration of the grain before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the grain is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the grain after application of highly propagating ultrasonic energy. The % increase in hydration due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of grain before and after application of highly propagating ultrasonic energy.

Table 4. H dration of barle usin hi hl ro a atin ultrasonic ener .

Highly propagating ultrasonic energy was applied to a mixture of lOOg rice grains in 50OmL using a 400 watt 2OkHz device at 7O 0 C. The test was conducted in an open container at ambient pressure. The moisture content was then measured by the method described above.

Table 5. H dration of rice usin hi hl ro a atin ultrasonic ener .

As can be seen from Table 4 the application of highly propagating ultrasonic energy increases the rate of hydration of water into rice grains by 10-20%.

Example 5. Highly propagating ultrasonic energy enhances liquid uptake into dairy based proteins and soya based proteins

The effect of highly propagating ultrasonic energy on the effect of water/liquid uptake into dairy based proteins and soya based proteins was tested.

Highly propagating ultrasonic energy was applied to a suspension of 10kg of whole milk powder in 50kg ' of water at a flow rate of 5 litres/min using 2OkHz ultrasound system operating at 1000 watts. The temperature was maintained at 5 0 C.

The level of mass transfer and hydration of the solid was measured by weighing out a lOOg portion of the solid material before addition to the liquid then placing that sample in an oven at 100 0 C for five hours before re- weighing that sample, the difference in weights indicates the level of hydration of the sample before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the solid is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the sample after application of highly propagating ultrasonic energy. The % increase in hydration due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of solid before and after application of highly propagating ultrasonic energy.

Table 6. Hydration of whole milk powder by highly propagating ultrasonic ener .

Highly propagating ultrasonic energy was applied to a suspension of 10kg of skimmed whole milk powder in 50kg of water using 2OkHz ultrasound system.

Highly propagating ultrasonic energy was applied to a suspension of 1 Okg of skimmed milk powder in 50kg of water at a flow rate of 5 litres/min using 2OkHz ultrasound system operating at 1000 watts. The temperature was maintained at 5 0 C. The hydration level was then measured by the method described above.

Table 7. Hydration of skimmed milk powder by highly propagating ultrasonic energy.

Highly propagating ultrasonic energy was applied to a suspension of 10kg of soya protein powder in 50kg of water at a flow rate of 5 litres/min using 2OkHz ultrasound system operating at 1000 watts. The temperature was maintained at 5 0 C. The hydration level was then measured by the method described above.

Table 8. Hydration of soya protein powder by highly propagating ultrasonic ener .

Example 6. Highly propagating ultrasonic energy enhances liquid uptake into starch.

The effect of highly propagating ultrasonic energy on the effect of water/liquid uptake into starch based materials was tested. Highly propagating ultrasonic energy was applied to a mixture of water and starch (ratio 10:1) at 6O 0 C using a 1000 watt 2OkHz probe.

The starch mixture gelatinized after 5 minutes application of highly propagating ultrasonic energy at 500 watts. The test was repeated and the starch mixture gelatinized in 3 minutes when highly propagating ultrasonic energy at 900 watts was applied. In contrast the starch mixture gelatinized in 7 minutes when subjected to conventional stirring.

Example 7. Highly propagating ultrasonic energy enhances hydration rate of corn.

Highly propagating ultrasonic energy was applied to a flow stream of corn and water before the mixture entered a conventional steeping tank. The highly propagating ultrasonic energy was applied using a 8kw 2OkHz unit. The corn water feed was 20 gpm (approximately 90 litres per minute) at 2O 0 C and 1 bar line pressure. After application of highly propagating ultrasonic energy the rate of hydration of the corn was measured and compared to a control sample processed under the same conditions but without the application of highly propagating ultrasonic energy.

The application of highly propagating ultrasonic energy to the flow stream of corn and water increases the hydration rate of the corn by 20%.

Example 8. Highly propagating ultrasonic energy enhances liquid uptake into gelatin.

The effect of highly propagating ultrasonic energy on the effect of water/liquid uptake into gelatin was tested by applying highly propagating ultrasonic energy to a mixture of water and gelatin (ratio 10:1) at 6O 0 C using a 1000 watt 2OkHz probe. The time to gelatinization was measured and compared to conventional stirring.

The gelatin mixture gelatinized after 5 minutes application of highly propagating ultrasonic energy at 500 watts. The test was repeated and the gelatin mixture gelatinized in 3 minutes when highly propagating ultrasonic energy at 900 watts was applied. In contrast the gelatin mixture gelatinized in 8 minutes when subjected to conventional stirring.

Example 9. Highly propagating ultrasonic energy enhances liquid uptake into carrageenan.

The effect of highly propagating ultrasonic energy on the effect of water/liquid uptake into carrageenan was tested by applying highly propagating ultrasonic energy to a mixture of water and carrageenan (ratio 10:1) at 9O 0 C using a 1000 watt 2OkHz probe. The time to gelatinization was measured and compared to conventional stirring.

The carrageenan mixture gelatinized after 6 minutes application of highly propagating ultrasonic energy at 500 watts. The test was repeated and the carrageenan mixture gelatinized in 3 minutes when highly propagating ultrasonic energy at 900 watts was applied. In contrast the carrageenan mixture gelatinized in 9 minutes when subjected to conventional stirring.

Example 10. Highly propagating ultrasonic energy enhances liquid uptake into xanthan gum.

The effect of highly propagating ultrasonic energy on the effect of water/liquid uptake into xanthan gum was tested by applying highly propagating ultrasonic energy to a mixture of water and xanthan gum (ratio 10:1) in a steel vessel at 2O 0 C using a 1000 watt 2OkHz probe operating at 500 watts and 2OkHz. The hydration level was measured and compared to a control which was stirred.

The level of mass transfer and hydration of the solid was measured by weighing out a lOOg portion of the solid material before addition to the liquid then placing that sample in an oven at 100 0 C for five hours before re- weighing that sample, the difference in weights indicates the level of hydration of the sample before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the solid is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the sample after application of highly propagating ultrasonic energy. The % increase in hydration due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of solid before and after application of highly propagating ultrasonic energy.

The xanthan gum was 86% hydrated after application of highly propagating ultrasonic energy at 500 watts (3 minutes). The test was repeated and the xanthan gum was 98% hydrated after application of highly propagating ultrasonic energy at 900 watts. In contrast xanthan gum was only 65% hydrated after conventional stirring (10 minutes). Example 11. Highly propagating ultrasonic energy enhances liquid uptake into palm fruit.

The effect of highly propagating ultrasonic energy on the effect of water/liquid uptake into palm fruit was tested by applying highly propagating ultrasonic energy to a mixture of crushed palm fruit and water at 65 0 C using a 2000 watt 2OkHz probe. The highly propagating ultrasonic energy was applied to the crushed palm fruit and water in a flow stream with a flow rate of 100 litres/min. The hydration level was measured and compared to a control sample to which highly propagating ultrasonic energy was not applied.

The crushed palm fruit was 36% hydrated when highly propagating ultrasonic energy was applied at 1000 watts and 44% hydrated when highly propagating ultrasonic energy was applied at 2000 watts. The crushed palm fruit in the control sample was 26% hydrated.

Example 12. Highly propagating ultrasonic energy enhances liquid uptake into corn germ

The effect of highly propagating ultrasonic energy on the effect of liquid uptake into corn germ was tested by applying highly propagating ultrasonic energy to a mixture of hexane and corn germ (ratio 4:1) in a steel vessel at 2O 0 C using a 1000 watt 2OkHz probe operating at 500 watts and 17-2OkHZ. The level of liquid transfer into the corn germ was measured and compared to a control which was stirred for 30 seconds

The level of liquid uptake into corn germ was measured by weighing out a lOOg portion of the corn germ before addition to the liquid then placing the grain in an oven at 100 0 C for five hours before re- weighing that corn germ, the difference in weights indicates the level of liquid in the corn germ before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the corn germ is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of liquid mass transfer into the corn germ after application of highly propagating ultrasonic energy. The % increase in liquid mass transfer due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of grain before and after application of highly propagating ultrasonic energy. Application of highly propagating ultrasonic energy at 500watts ( for 30 seconds results in 75% liquid to solid transfer while application of highly propagating ultrasonic energy at 900watts ( for 30 seconds) results in 98% liquid to solid transfer. Conventional stirring for 30seconds results in 25% liquid to solid transfer.

Example 13. Highly propagating ultrasonic energy and heat synergistically enhance liquid uptake.

The effect of highly propagating ultrasonic energy combined with heat on the effect of water/liquid uptake into corn germ was tested by applying highly propagating ultrasonic energy to a mixture of hexane and corn germ in a steel vessel (ratio 4:1) at 5, 10 and 2O 0 C using a 1000 watt 2OkHz probe operating at 500 watts and 17-2OkHZ for 30 seconds. The level of liquid transfer into the corn germ was measured and compared to a control which was stirred for 30 seconds.

The level of liquid uptake into corn germ was measured by weighing out a lOOg portion of the corn germ before addition to the liquid then placing the grain in an oven at 100 0 C for five hours before re-weighing that corn germ, the difference in weights indicates the level of liquid in the corn germ before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the corn germ is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of liquid mass transfer into the corn germ after application of highly propagating ultrasonic energy. The % increase in liquid mass transfer due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of grain before and after application of highly propagating ultrasonic energy.

At 5 0 C application of highly propagating ultrasonic energy at 500watts results in 55% liquid to solid transfer while application of highly propagating ultrasonic energy at 900watts results in 78% liquid to solid transfer. Conventional stirring for 30seconds results in 5% liquid to solid transfer.

At 1O 0 C application of highly propagating ultrasonic energy at 500 watts results in 64% liquid to solid transfer while application of highly propagating ultrasonic energy at 900watts results in 87% liquid to solid transfer. Conventional stirring for 30seconds results in 17% liquid to solid transfer.

At 2O 0 C application of highly propagating ultrasonic energy at 500watts results in 75% liquid to solid transfer while application of highly propagating ultrasonic energy at 900watts results in 98% liquid to solid transfer. Conventional stirring for 30seconds results in 25% liquid to solid transfer.

Example 14. Highly propagating ultrasonic energy and pressure synergistically enhance liquid uptake.

Highly propagating ultrasonic energy was applied to a mixture of lOOg rice grains in 50OmL water using a 500 watt 17-2OkHz device at 7O 0 C at various pressures and in an open steel container at ambient pressure.

The level of liquid uptake into rice was measured by weighing out a 10Og portion of the grain before addition to the liquid then placing the rice in an oven at 100 0 C for five hours before re- weighing that rice, the difference in weights indicates the level of hydration of the rice before application of highly propagating ultrasonic energy. After application of highly propagating ultrasonic energy to the mixture a lOOg sample of the rice is weighed out then placed in an oven at 100 0 C for five hours and weighed again, the difference in weights indicates the level of hydration of the grain after application of highly propagating ultrasonic energy. The % increase in hydration due to the application of highly propagating ultrasonic energy is then calculated from the weight differences of rice before and after application of highly propagating ultrasonic energy.

Table 9 illustrates that the application of highly propagating ultrasonic energy to a rice and water mixture in an open container at ambient pressure increases hydration of rice grains by 10-20%.

Table 9. Effect of sonication of h dration of rice at ambient pressure

When the test was repeated at 1 bar pressure the application of highly propagating ultrasonic energy for 3 minutes resulted in 26% hydration of the rice.

When the test was repeated at 2 bar pressure the application of highly propagating ultrasonic energy for 3 minutes resulted in 36% hydration of the rice. When the test was repeated at 3 bar pressure the application of highly propagating ultrasonic energy for 3minutes resulted in 39% hydration of the rice.

Example 15. Highly propagating ultrasonic energy and a vacuum synergistically enhance mass transfer.

The effect of highly propagating ultrasonic energy combined with a vacuum on the filtration rate of a gluten protein starch slurry was tested by applying highly propagating ultrasonic energy to the slurry at 500 watts, 2OkHZ and 5 micron amplitude. The slurry was maintained at 5 0 C. The filtration rate through a vacuum filter was measured. The filtration rate of a gluten protein starch slurry which was not subjected to highly propagating ultrasonic energy was measured at 2 gpm (approximately 9 litres/min). On the application of highly propagating ultrasonic energy the filtration rate was measured as 2.9 gpm (approximately 13 litres/min), an improvement of 0.9 gpm (approximately 4 litres/min).

Example 16. Highly propagating ultrasonic energy and conventional mixing synergistically enhance liquid uptake.

The effect of highly propagating ultrasonic energy combined with conventional mixing/homogenizing technology to enhance liquid mass transfer or hydration of liquids into food, agricultural or non-food products was tested by applying highly propagating ultrasonic energy to a mixture of 0.5kg of soya protein powder in 50kg of orange juice. Highly propagating ultrasonic energy at 100% amplitude was applied to this mixture as it was pumped through a lkw, 2OkHz highly propagating ultrasonic energy system at 10 litres per minute. This treatment resulted in a 38% hydration level of the soya protein.

A control test was performed using a mixture of 0.5kg of soya protein powder in 50kg of orange juice subjected to high shear homogenisation. The hydration level of the soya protein after homogenization was 14%.

When a mixture of 0.5kg of soya protein powder in 50kg of orange juice was subjected to high shear homogenisation and highly propagating ultrasonic energy at 100% amplitude as it was pumped through a lkw, 2OkHz highly propagating ultrasonic energy system at 10 litres per minute, hydration level of the soya protein was 46%.




 
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