FIELD OF THE INVENTION:

The present invention relates to the area of preparing a variety of valuable products from hemp seeds. In particular, the present invention relates to process and system for preparing hemp milk, hemp oil and hemp proteins with purity in excess of 90% from hemp seeds.

BACKGROUND OF THE INVENTION:

History shows that hemp seeds as a food source go back thousands of years. Documents show that hemp was an important source of protein, fiber, and medicine in the Mediterranean, Egypt, and Morocco many centuries B.C.

Hemp seeds are nutritious, are a great source of plant-based proteins, have the ability to reduce risk of heart disease, have the ability to reduce symptoms of PMS and menopause and have the ability to aid digestion. Because of the above, heed seeds are a subject matter of intensive research.

While hemp seeds have a variety of beneficial components, the prior arts processes do not lead to extraction of all of the beneficial components.

For instance, there are a variety of prior arts which describe extraction of Hemp milk from hemp seeds. Hemp milk is plant-based milk growing in popularity. Commercial hemp seed, used in the production of hemp milk, contains only trace amounts of the compound tetrahydrocannabinol (THC), much too low to produce any psychoactive effects from consuming the milk. Some of the benefits of hemp milk include appropriateness for allergies or intolerances to cow/buffalo’s milk, because it does not contain any milk proteins or the milk sugar lactose. Therefore, individuals allergic to cow/buffalo’s milk proteins, or with some degree of lactose intolerance, may safely consume hemp milk. Hemp is not one of the eight major food allergens, an advantage over almond and soy milk. Hemp milk is a source of unsaturated fats. The Dietary Guidelines for Americans recommends replacing saturated with unsaturated fats because it may reduce the risk of cardiovascular disease. Commercial hemp milk is made by combining the hemp seed with water. First, the hemp seeds are mixed with hot water; they swell and soften as they absorb water. This hot slurry of hemp seeds and water is then wet-milled until the desired consistency is reached. The filtered slurry is homogenized for stability and then cooled to stop oxidation of the oils and vitamins. Water, emulsifiers, stabilizers, sweeteners, and flavorings are added to customize the hemp milk. Finally, aseptic processing, such as ultra-high temperature (UHT) treatment, is carried out to extend the product shelf life.

For instance, CA2505350 discloses a method for producing hemp milk, during the course of which hemp seeds are ground and mashed with water, the seeds are extracted by means of heated water, and the raw hemp milk obtained is separated from the solid particles of the hemp seeds. As per the document, in order to obtain non-graying, pasteurizable and sterilizable hemp milk that does not have a bitter taste, once the hemp seeds have been steeped in water at between 15° and 50°C and washed, they are either a) ground while being heated to a temperature of between 80° and 90°C, whereupon extraction takes place at temperatures of below 80°C, or b) first ground at between 0°C and 80°C and then subjected to hot water pulping or extraction at temperatures of between 80° and 90°C, whereupon the raw hemp milk is separated from the hemp seed husk particles and is then supplied to the consumer, either directly in its fresh state, or after secondary treatment, pasteurization, heat sterilization or the like. The document does not describe obtaining products other than hemp milk.

For example, a further development of hemp milk recovery has become known from RU 2185069 C2 which consists in that the entire hempseed is allowed to germinate up to the moment when germs of a size of 1 to 2 mm appear, this germ size being the essential criterion and not the duration of soaking and germinating. Subsequently, the seeds, having begun to germinate, are ground, after which extraction in hot water at a "hydromodule" of 1.3 to 1.5 will follow, and the hemp milk is separated from solid residues of the seeds. The document does not describe obtaining products other than hemp milk.

DE19833567 describes a method for producing hemp milk from hemp seeds, which consists of subjecting the seeds to swelling at temperature of 8° to 10° C for about 20 hours, and crushing the soaked seeds at temperature of about 1° C whereupon the raw hemp milk is separated from solid residues of the seeds. The document also indicates that the hemp milk thus obtained is subjected to thermal denaturation and precipitation without using a precipitant to obtain hemp tofu. The document does not describe obtaining products other than hemp milk (or hemp tofu).

RU 2341093 discloses a method of making hemp milk, in which cannabis seeds are rubbed clean and soaked in water for 5-12-hour at temperatures in the range of 5° to 35°C. Thereafter, the soaked seeds are subjected to grinding and hot extraction at temperature of about 80° to 90°C to obtain a mashed mass. The mashed mass is then subjected to cold extraction at temperature of about 0° to 10°C to obtain hemp milk. The document does not describe obtaining products other than hemp milk.

On the other hand, when it comes to extraction of oil from hemp seeds, a variety of processes are available.

For instance, there is available CO2 based cannabis oil extraction process. There is further available hydrocarbon extraction based process which uses a hydrocarbon, such as butane or propane, as a solvent. The hydrocarbon is washed over the plant matter in order to break it down, before ultimately concentrating a targeted molecule and removing it from the biomass. The hydrocarbon extraction process has high efficiency, a higher yield rate, preserves different terpenes than other methods and equipment is affordable. However, this method of extraction comes with its own set of drawbacks. Chemicals like butane are volatile gases and obviously have a high potential for combustion and flammability, resulting in zoning and storage limitation laws put in place for safety purposes. Consequently, this creates limitations on scalability for operations looking to expand. If a manufacturer is looking to scale, hydrocarbon extraction is not advised. Apart from the above, when the hydrocarbon based extraction process is adopted, products other than hemp oil is not obtained.

By way of another example, there is also available, an ethanol based hemp oil extraction process. The ethanol based hemp oil extraction process is simple and scalable. The real advantage to this method is its ability to effectively scale up within manufacturing operations, especially after the extraction has been done with cold ethanol below -40°C. Winterisation uses ethanol and sub-zero temperatures to separate unwanted fats and waxes from the oil: that is why the oil extracted this way is with almost no fats and lipids and looks like post-winterised crude. The major disadvantage of ethanol is that it denatures the oil. Another disadvantage of ethanol is the high boiling point of around 80°C. This means that in order to be separated from the extract the temperature may exceed 100°C, the boiling temperature of water; so, as a result the separated solvent will be diluted in the plant residual moisture. The boiling point of the terpenes is 120°C to 180°C, which means that the ethanol- water solution will already be contaminated with terpenes and will need to be purified after each run to keep the consistency of the extracts same every time. This process brings a loss of the solvent at around 15% to 20% of the extractor volume at every run which increases the operational cost of the extraction significantly especially when in scale. Also, when the hydrocarbon based extraction process is adopted, products other than hemp oil is not obtained.

Another method for cannabis oil extraction is through the use of a tetrafluoroethane (TFE), R134a, as a solvent. R134a by itself is often used in aerosol products for drug delivery. Products which are extracted using this method are called post-winterised full spectrum oils ; the level of wax present in the extract right off the machine is usually less than 5% or even less than 2% in most cases. Apart from the above, when R134a is used as a solvent, products other than hemp oil is not obtained.

Now coming to the aspect of hemp protein extraction, US20130202777A1 describes a process comprising the steps of a) soak and clean the hemp element as necessary; b) measure hemp seed/nut element to add to high shear processing blender; c) add water to blender in proportion to desired end product; d) emulsify until green oil is evident and green matrix is rough and stiff, forming a gluten-like matrix; and e) add protein if desired and blend free oil back into the matrix, which ameliorates the protein quality. Since the main point of the whole document is hemp protein, the document does not describe obtaining any further products. Reference may also be made to US20080241339A1 that discloses a food making process comprising: cooking hemp seeds in water to hydrate and soften them for shell removal and grinding; wet milling a resulting slurry in a loop to remove fibrous material from the hemp seeds; filtering out solids from said slurry; homogenizing a liquid base filtered from the slurry; cooling said liquid base to stop oxidation; wherein said liquid base is used in further processing to produce a food. Since the main point of the whole document is hemp protein, the document does not describe obtaining any further products.

Thus, there exists a need to provide a process and a system for producing a variety of valuable products from hemp seed, which will make the project commercially feasible.

SUMMARY OF THE INVENTION:

This summary is provided to introduce a selection of concepts in a simplified format that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention, and nor is it intended for determining the scope of the invention.

The present invention provides a process for preparing hemp milk, hemp oil and hemp proteins from hemp seeds. In particular, the present invention provides a process which sequentially extracts hemp milk, hemp oil and hemp protein from hemp seeds thereby maximizing the number of products that are prepared from hemp seeds. In particular, the process comprises processing the hemp seeds and recovering hemp milk and hemp cake from the hemp seeds; processing the hemp cake and recovering residual hemp oil and residual cake from the hemp cake; and processing the residual cake for recovering hemp protein having purity in excess of 90% therefrom.

Additionally, the present invention provides a system for preparing hemp milk, hemp oil and hemp proteins from hemp seeds. In particular, the present invention provides a system which sequentially extracts hemp milk, hemp oil and hemp protein from hemp seeds thereby maximizing the number of products that are prepared from hemp seeds. In particular, the system comprises a first sub-system adapted to process the hemp seeds and recover hemp milk and hemp cake from the hemp seeds; a second sub-system operably coupled to the first sub- system, the second sub-system being adapted to process the hemp cake and recover residual hemp oil and residual cake from the hemp cake; and a third sub-system operably coupled to the second sub-system, the third sub-system being adapted to process the residual cake and recover hemp protein having purity in excess of 90% therefrom.

To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES:

In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying drawings. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present invention where:

Figure 1 demonstrates the process for preparing hemp milk, hemp oil and hemp proteins from hemp seeds in accordance with an embodiment of the invention;

Figure 2 demonstrates a more detailed process for preparing hemp milk, hemp oil and hemp proteins from hemp seeds in accordance with an embodiment of the invention;

Figure 3 demonstrates a block diagram of a system for preparing hemp milk, hemp oil and hemp proteins from hemp seeds in accordance with an embodiment of the invention; and Figure 4 demonstrates a more detailed block diagram of the system for preparing hemp milk, hemp oil and hemp proteins from hemp seeds in accordance with an embodiment of the invention.

It may be noted that to the extent possible, like reference numerals have been used to represent like steps in the drawings. Further, skilled artisans will appreciate that the steps are illustrated for simplicity in the form of blocks, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF THE INVENTION:

For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.

As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

As used herein, and unless the context dictates otherwise, the terms "coupled to", “connected to”, “operably connected to”, “operatively connected to” are intended to include both direct connection / coupling (in which two elements that are coupled / connected to each other contact each other) and indirect coupling / connection (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously. Similarly, the terms “connected to” and “connected with” are used synonymously.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The methods, devices, and examples provided herein are illustrative only and not intended to be limiting.

The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims. Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Referring to Figure 1, there is illustrated a block diagram of a process (100) for preparing hemp milk, hemp oil and hemp protein from hemp seeds. In particular, the process (100) involves sequentially extracting hemp milk, hemp oil and hemp protein from hemp seeds thereby maximizing the number of products that are prepared from hemp seeds. More particularly, the process (100) comprises processing the hemp seeds and recovering hemp milk and hemp cake from the hemp seeds (102); processing the hemp cake and recovering residual hemp oil and residual cake from the hemp cake (104); and processing the residual cake and recovering hemp protein having purity in excess of 90% therefrom (106).

Referring to Figure 2, there is illustrated a more detailed block diagram of the process (100) for preparing hemp milk, hemp oil and hemp protein from hemp seeds. In particular, processing the hemp seeds and recovering hemp milk and hemp cake from the hemp seeds (102) comprise adding water to hemp seed and grinding the same in an airless grinder to obtain first slurry (108). The first slurry is extracted with water and filtered (110) to recover hemp milk (112) and hemp cake (114). The hemp milk thus recovered can be processed for further use.

It can be furthermore seen that processing the hemp cake and recovering residual hemp oil and residual cake from the hemp cake (104) comprises subjecting the hemp cake thus recovered to solvent based extraction (116). After the solvent based extraction has been completed, residual cake is separated (118) and hemp oil is recovered (120). Thus, it can be seen that hemp oil is recovered after hemp milk is recovered from the hemp seed and from the hemp cake which is left thereafter.

It can be furthermore seen that processing the residual cake and recovering hemp protein therefrom (106) comprises adding water and alkali to the residual cake to obtain second slurry (122). The second slurry is optionally heated (124) to a temperature of up to 80°C. The second slurry (or alternatively the heated second slurry) is subjected to separation (126) to obtain a liquid fraction and a residual mass (128). To the liquid fraction thus obtained, acid is added to induce precipitation (130). The precipitate is recovered and dried to obtain hemp protein (132). Thus, it can be seen that hemp protein is recovered after hemp oil is recovered and more particularly from the residual cake which is left after extraction of the hemp oil.

Now coming specifically to the process of preparing the first slurry (108), in an embodiment of the invention, the hemp seeds are mixed with water and are allowed to soak for about 0.5 to 6 hours. The temperature of the water which is used for soaking is maintained in the range of 30°C to 40°C. Thereafter, the soaked hemp seeds along with the water are ground. The grinding can be performed in an air less grinding system. In an embodiment of the invention, a temperature of the material being ground may be maintained at a value less than about 120°C.

Now coming specifically to the step of extraction of the first slurry (110), in an embodiment of the invention, water is added to the first slurry to obtain a mixture, which is then heated to a temperature in the range of 100°C to 120°C to affect extraction. Steam may be used for the purposes of heating in accordance with a non-limiting embodiment of the invention. Subsequent to extraction, the mixture is subjected to filtration to obtain raw hemp milk and hemp cake.

The raw hemp milk thus obtained may be homogenized and then cooled. Water, emulsifiers, stabilizers, sweeteners, and flavorings may be added to customize the hemp milk. Finally, aseptic processing, such as ultra-high temperature (UHT) treatment, may be carried out to extend the product shelf life.

The hemp cake thus recovered is subjected to solvent based extraction to obtain hemp oil. Now coming specifically to the process of solvent based extraction (116), in an embodiment of the invention, the hemp cake is mixed with the solvent which may be hexanol or ethanol or a combination thereof and heated up to 50°C for about 30 minutes in an agitated solvent extraction plant.

Once the hemp cake has been extracted with solvent, the oil components are carried by the solvent leaving behind a residual cake. The solvent-oil mixture is then subjected to distillation so as to separate the solvent and raw oil. The raw oil may be suitably refined to obtain hemp seed oil. The solvent thus recovered is re-used for the extraction purposes.

Now the residual cake is suitably processed to obtain hemp protein. Now coming specifically to the process of obtaining the hemp protein, water is added to the residual cake and alkali is added to obtain second slurry. The quantity of alkali added is such that the pH of the second slurry is maintained in the range of 8.5 to 9.0. A variety of alkalis can be added in the aforesaid step including but not limited to NaOH, KOH, LiOH, Mg(0H)2, etc. The second slurry is then heated to a temperature of up to 40°C to obtain a reaction mass. The reaction mass is then subjected to filtration to obtain a liquid fraction and residual mass.

The liquid fraction is heated up to 60°C and thereafter an acid is added, which causes precipitation of hemp proteins. The quantity of acid added is such that the pH of the liquid fraction is maintained in the range of 4.2 to 4.5. A variety of acids can be added in the aforesaid step including but not limited to HC1, HF; HI; HBr; H2SO4, HNO3, CH3COOH, etc. The precipitate is recovered and subjected to drying to obtain hemp protein. The residual mass on the other hand, is suitable for use as cattle feed.

Now coming to the system perspective, as shown in Figure 3, the system (200) for preparing hemp milk, hemp oil and hemp proteins from hemp seeds in accordance with an embodiment of the invention comprises a first sub-system (202) adapted to process the hemp seeds and recover hemp milk and hemp cake from the hemp seeds; a second sub-system (204) operably coupled to the first sub-system (202), the second sub-system (204) being adapted to process the hemp cake and recover hemp oil and residual cake from the hemp cake; and a third sub-system (206) operably coupled to the second sub-system (204), the third sub-system (206) being adapted to process the residual cake and recovering hemp protein therefrom.

Now referring particularly to Figure 4, the first sub-system (202) comprises a grinding unit (208) adapted to produce first slurry by grinding a mixture of hemp seeds and water. The first sub-system (202) further comprises an extraction and filtration unit (210) which extracts the first slurry with water and filters the same to recover hemp milk and hemp cake. The second sub-system (204) comprises a solvent based extraction unit (212) which receives the hemp cake, brings the hemp cake in contact with the solvent and removes a mixture of solvent and hemp oil leaving behind residual cake. The second sub-system (204) further comprises a distillation unit (214) which separates the hemp oil from the mixture of solvent and hemp oil. The solvent thus recovered in the distillation unit (214) can be re-used in the solvent based extraction unit (212).

The third sub-system (206) comprises a reaction tank (216) which receives residual cake. The reaction tank (216) may be provided with stirring means (not specifically shown) so that residual cake along with water and alkali can be mixed to form the second slurry. There may be provided a heating unit (218) for heating the second slurry and obtain the reaction mass. The third sub-system (206) further comprises a filtration unit (220) which filters the reaction mass to obtain the liquid fraction and residual mass. The third sub- system may further comprise a precipitation unit (222) in which the liquid fraction can be brought in contact with an acid to induce precipitation of the hemp proteins. The precipitate is recovered from the precipitation unit (222) and may optionally be dried in drier (224). The reaction mass may be subjected to drying to obtain cattle feed.

Reference is drawn to the following example to illustrate the process of invention.

Example 1: Hemp milk extraction from hemp seeds

10 kg of hemp seeds are mixed with warm water and are allowed to soak for about 2 hours. The temperature of the water which is used for soaking is about 40°C. Thereafter, the soaked hemp seeds along with additional water are ground in an airless grinder to obtain the first slurry, which is then heated to a temperature of about 110°C and held for about 1-2 minutes. Subsequent to heating, the mixture is subjected to filtration to obtain 30 kg of raw hemp milk and 25.6 kg of hemp cake containing 75% of moisture.

Example 2: Hemp oil extraction from hemp cake of Example 1

25.6 kg of hemp cake as obtained in Example 1 containing 75% of moisture is dried and subjected to solvent based extraction process using Ethyl alcohol. The solvent based extraction process yields 2.7 kg of hemp oil and 4.2 kg of residual cake. Example 3: Cattle feed production from residual cake of Example 2

20 kg of water and NaOH is added to 4.2 kg of the residual cake and agitated for about 30 minutes to obtain second slurry having pH in the range of 8.5-9.5. The second slurry is thereafter filtered to obtain 9.5 kg of the liquid fraction and 14.75 kg of residual mass. The residual mass is having 80% moisture content. The residual mass contains carbohydrates, minerals, proteins and can be other elements and can be used as a cattle feed after drying.

Example 4: Hemp Protein extraction from the liquid fraction of Example 3

To the 9.5 kg of the liquid fraction obtained in Example 3, HC1 acid is added. The quantity of acid added is such that the pH of the liquid fraction is maintained at about 3.5. The addition of acid results in precipitation of hemp proteins. The precipitate is recovered and subjected to drying to obtain hemp protein of 1.25 kg with 90% purity.

Apart from the above, hemp oil is extracted from the hemp seeds directly. After hemp oil is extracted from the hemp seeds, a residual mass is left out. Attempts were made to extract either hemp milk or hemp protein, but none was successful.

In yet another case, hemp milk is extracted from the hemp seeds leaving behind hemp cake. Instead of extracting hemp oil from the hemp cake, attempts are made to extract hemp protein using the same procedure as mentioned above. However, such attempts were not successful.

In light of the above, it can be concluded that all of hemp milk, hemp oil and hemp protein are extracted from hemp seeds only if sequential extraction as specifically described is followed and not otherwise.

Thus, it can be observed that the present invention produces a variety of value added products from hemp seeds. As each of the value added product has significant demand in market, the person implementing the process can earn more amount of money by selling these value added products. It can be seen that in the earlier processes, these value added products were not recovered separately. While certain present preferred embodiments of the invention have been illustrated and described herein, it is to be understood that the invention is not limited thereto. Clearly, the invention may be otherwise variously embodied, and practiced within the scope of the following claims.