The present invention relates to the use of ultrafine solid particles for improving chocolate temper recovery after exposure to high temperatures, particularly at temperatures higher than 34°C.

The present relation also relates to a chocolate confectionery composition containing ultrafine solid particles, and to a process for its manufacture.

The process of making chocolate involves a succession of processing steps, which comprises, inter alia, grinding the cocoa mass obtained from ground cocoa nibs mixed with sugar and milk powder (in case of milk chocolate), adding fat (usually, cocoa butter and lecithin) thereto and conching, which results in a chocolate mixture which will be further transformed into the desired final product, such as bars, sweets, coatings etc.

In particular, the chocolate mixture post conching, sometimes called chocolate mass, is submitted to a tempering process, which consists in applying heating, cooling and reheating combined with shearing.

Tempering provides the shearing of the chocolate mass at controlled temperatures (32°C to 34°C), so that the thermodynamically stable form of beta-polymorphic crystals of cocoa butter is obtained, which gives the desired glossy appearance, texture and sensorial attributes to the final chocolate product.

When chocolate is exposed to a temperature above 34°C, the beta-polymorphic crystals of cocoa butter are transformed into less stable polymorphs upon melting. This process is commonly referred to as "loss of chocolate temper". If the chocolate is subsequently cooled down, it will set up into a dull, soft and brittle texture with different sensorial attributes, and with time it will develop whitish crystal stains on the surface, known as "fat bloom".

In order to regain the beta-polymorphic crystal form, the chocolate must go through a tempering process.

Loss of temper is one of the most critical causes of chocolate quality defects, and this problem is particularly acute in tropical countries. Several solutions were proposed to improve the chocolate temper resistance, which includes the use of higher-temperature melting fats. However, such products have a negative impact on the chocolate in-mouth texture, which is felt waxy and slow-melting.

WO2010/148058 discloses a chocolate composition containing nanoparticles of nutritive carbohydrate sweetener (e.g. sucrose), in order to improve temperature shape stability properties.

There is thus a need for providing a chocolate composition or a process for manufacturing a chocolate composition where the chocolate mass can self-repair its temper, i.e. recover spontaneously the beta-polymorphic crystal form, after it has been exposed to a temperature higher than 34°C and then cooled down.

Broadly in accordance with one aspect of the invention there is provided a fat based confectionery composition, comprising 1 % or less by weight of a solid material consisting of food grade hydrophilic ultrafine particles having a size (dgo) below 0.2 microns, the weight percent being based on the weight of the fat based confectionery composition being 100%.

In a further aspect of the invention, there is provided a process for manufacturing a chocolate confectionery composition, comprising a step of adding 1 % or less by weight of a solid material consisting of food grade hydrophilic ultrafine particles having a size (dgo) below 0.2 microns the weight percent being based on the weight of the fat based confectionery composition being 100%.

Preferably the fat based confectionery composition of or prepared by the process of the invention comprises a chocolate confectionery composition.

In a third aspect, there is provided the use of ultrafine solid particles for enabling the chocolate to self-repair its temper after exposure to high temperatures.

Figure 1 shows a DSC thermograph of two compositions, where Example 1 is a composition according to the invention, and Comp A, used as a control, is substantially free of ultrafine particles having a size (dgo) below 0.2 microns.

Surprisingly the applicants have found that adding to a chocolate confectionery composition, 1 % or less by weight of a solid material consisting of food grade hydrophilic ultrafine particles having a size (dgo) below 0.2 microns, the weight percent being based on the weight of the fat based confectionery composition being 100%, the chocolate composition could self-repair its temper, i.e. that the cocoa butter could recover spontaneously the beta-polymorphic crystal form, after the composition has been exposed to a temperature higher than 34°C and then cooled down to standard temperature.

The particle size values given herein may be measured by laser diffractometry (for example as described in Industrial Chocolate Manufacture and Use, editor Steve Beckett, fourth edition, 2009, Section 22.3.4. 'Particle size measurement', pages 522 to 524, the contents of which are incorporated herein by reference.). A suitable instrument to measure particle size from laser diffraction is a 'Coulter LS230 Particle Size Analyser'. Particle size is determined by measuring the volume distribution of the sample by plotting volume (%) versus size (microns) (e.g. see Figure 22.24 of Beckett). Particle size is then quoted as the linear dimension which corresponds to the diameter of an approximate spherical particle having the same volume as the mean volume calculated from the measured volume distribution. A normal particle size distribution (PSD) with single maximum peak (mono modal) is assumed in most cases for the particles used in the present invention. However other PSDs (e.g. multimodal such as bimodal) are not excluded from this invention.

As an alternative measure of particle size, the measure d _n may be used (also expressed in linear dimensions) which denotes the size of particle below which n% (by number) of the particles in a given particle sample lie. In this alternative a useful measure of particle size is where n is 50 (i.e. size is measured as dso), more usefully n is 70 (i.e. size is measured as d ₇₀ ), most usefully n is 90 (i.e. size is measured as dgo).

By "particles having a size below 0.2 microns" preferably denotes that the particles in a given particle sample have a size (dgo) less than 0.2 microns (= 200 nanometres). Preferably, the particles of the solid material described herein have a size (dgo) of from 5 nanometres to less than 0.2 microns more preferably from 5 to 100 nanometres, most preferably from 5 to 50 nm, for example from 5 to 20 nm.

As used herein the term 'chocolate' comprises any ingredient with cocoa or cocoa-derived fatty solids, whether or not they meet any legal or other formal definition of chocolate used in other contexts. Thus as used herein the term 'chocolate' encompasses ingredients having no cocoa butter (also referred to as 'compound') and/or also white chocolate or white compound. A chocolate coating is also referred to herein as a chocolate shell. Optionally the fat based compositions (such as fat based confectionery) of the invention may also comprises chocolate and/or similar ingredients (e.g. with similar taste). The terms 'chocolate compound' or 'compound' as used herein (unless the context clearly indicates otherwise) denotes a chocolate analogue in which all or part of the cocoa butter is replaced by cocoa butter equivalents (CBE) or cocoa butter replacers (CBR). The terms "chocolate confectionery composition" as used herein denotes a chocolate composition which is processed for manufacturing a final chocolate confectionery product which term also includes chocolate compound products.

Without wishing to be bound by theory, it may be hypothesized that the ultra-fine particle may form a network which appears to restrict the movements of cocoa butter molecule aggregates and solid particulates in the chocolate product. Thus, during the heating and subsequent cooling of tempered chocolate, the cocoa butter molecules and aggregates may maintain a molecular conformation which is well suited to recrystallization into beta crystals.

The solid material consisting of food grade hydrophilic ultra-fine particles having a size below 0.2 microns can, for example, be present in the chocolate composition in an amount of from 0.3% to 1 % by weight of the total chocolate composition being 100%.

The food grade hydrophilic ultra-fine particles are advantageously ultrafine nutrient crystalline particles, such as for instance calcium carbonate, calcium sulphate, iron oxide, silica oxide, magnesium citrate, sugar or other ultrafine nutrient crystalline particles. Said solid material consisting of food grade hydrophilic ultra-fine particles can, for example, be selected from sugar particles, sweetener particles and silica oxide particles.

In particular, said solid material described herein can comprise at least 1 part by weight of the total amount of all sugar in the confectionery composition being 100 parts. For instance, at least 1 part of the amount of sugar in the chocolate confectionery composition comprises sucrose particles having a size below 0.2 microns, preferably from 5 nanometres to below 200 nanometres.

The chocolate confectionery composition according to the invention contains cocoa powder, milk fat, milk powder and may contain at least one ingredient selected from emulsifiers, sugars, natural or artificial sweeteners, flavouring agents, nuts and fruits.

The invention further relates to process for manufacturing a chocolate confectionery composition, comprising a step of adding 1 % or less by weight of a solid material consisting of food grade hydrophilic ultra-fine particles having a size below 0.2 microns.

Preferably, the addition of the solid material is carried out during the mixing step following conventional processing conditions used for the pre-refiner mass preparation, or together with chocolate flakes in the conch. Alternatively the food grade hydrophilic ultra-fine particles can be added into the molten chocolate mass and blended in a conch or other suitable blender to ensure complete dispersion of the ultrafine particles.

The invention further relates to the use of a solid material consisting of food grade hydrophilic ultrafine particles having a size below 0.2 microns for improving the chocolate temper- resistance at temperatures higher than 34°C. Preferably, this use comprises a step of adding said solid material to the chocolate mass during the mixing step following conventional processing conditions used for the pre-refiner mass preparation, or together with chocolate flakes in the conch.

Said solid material is preferably selected from sugar particles, sweetener particles and silica oxide particles.

The preferred features mentioned above for the chocolate confectionery composition apply equally to the process for its manufacture, and to the use of a solid material consisting of food grade hydrophilic ultra-fine particles for improving the chocolate temper-resistance, according to the invention.

Further aspects and preferred features of the present invention are described in the claims.

TEST METHODS AND DEFINITIONS

Unless defined otherwise, all technical and scientific terms have and should be given the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

RANGES

In the discussion of the invention herein, unless stated to the contrary, the disclosure of alternative values for the upper and lower limit of the permitted range of a parameter coupled with an indicated that one of said values is more preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and less preferred of said alternatives is itself preferred to said less preferred value and also to each less preferred value and said intermediate value.

For all upper and/or lower boundaries of any parameters given herein, the boundary value is included in the value for each parameter. It will also be understood that all combinations of preferred and/or intermediate minimum and maximum boundary values of the parameters described herein in various embodiments of the invention may also be used to define alternative ranges for each parameter for various other embodiments and/or preferences of the invention whether or not the combination of such values has been specifically disclosed herein.

PERCENTAGES

It will be understood that the total sum of any quantities expressed herein as percentages cannot (allowing for rounding errors) exceed 100%. For example the sum of all components of which the composition of the invention (or part(s) thereof) comprises may, when expressed as a weight (or other) percentage of the composition (or the same part(s) thereof), total 100% allowing for rounding errors. However where a list of components is non exhaustive the sum of the percentage for each of such components may be less than 100% to allow a certain percentage for additional amount(s) of any additional component(s) that may not be explicitly described herein.

All percentages for amounts are given in percent by weight, if not otherwise indicated and applicable.

IMPROVEMENTS / COMPARABLE PROPERTIES Compositions of and/or used in the present invention may also exhibit improved properties with respect to known compositions that are used in a similar manner. Such improved properties may be (preferably as defined below) in at least one, preferably a plurality, more preferably three of more of those propert(ies) labeled 1 to 5 below. Preferred compositions of and/or used in the present invention, may exhibit comparable properties (compared to known compositions and/or components thereof) in at least one, more preferably at least two, even more preferably at least three, most preferably at least four, for example all of those properties labeled 1 to 5 below.

1 ) Reduced SFA content being defined as less than 65% total fat content being SFA;

2) Resistance to visual defects due to heat exposure (bloom resistance) being defined as having a visual rating of at least 4 after being subject to temperature Regime 2;

3) Stability against heat damage being defined as having at least 80% of the sample surface free of damage after being subject to temperature Regime 1 ;

4) Sheen (gloss retention) after heat exposure under Regime 1 being rated as G or M, preferably G.

5)Auto-tempering as defined herein.

Improved properties as used herein means the value of the property of the component and/or the composition of and/or used in the present invention, where it can be measured quantatively, is > +8% of the value of the known reference component and/or composition described herein, more preferably > +10%, even more preferably > +12%, most preferably > +15%.

Comparable properties as used herein means the value of the property of the component and/or composition of and/or used in the present invention, where it can be measured quantatively, is within +/-6% of the value of the known reference component and/or composition described herein, more preferably +/- 5%, most preferably +/- 4%.

The percentage differences for improved and comparable properties herein refer to fractional differences between the component and/or composition of and/or used in the invention and the known reference component and/or composition described herein where the property is measured in the same units in the same way (i.e. if the value to be compared is also measured as a percentage it does not denote an absolute difference).

The reference composition used to measure improvement or comparability is preferably a composition analogous to those of the present invention that comprise a Triglyceride Blend, where the Triglyceride Blend is replaced by the same total amount by weight of one SUS triglyceride selected from any as described for Ingredient (i) herein all other ingredients remaining unchanged.

BLOOM RESISTANCE

Immediately prior to being tested for bloom resistance, the samples to be tested were pre- stored at 20°C in temperature-controlled cabinets and their appearance assessed to provide a comparison to the appearance after the test.

To assess bloom resistance the test sample was then subjected to a specific temperature storage regime (where the samples were also stored in temperature-controlled cabinets during these tests) which unless otherwise specified is one or more of those temperature regimes described below.

Regime 1 (also referred to herein as Isothermal Storage) denotes that the samples were heated to 60°C to fully melt the fat and subsequently stored at 20°C. The appearance of bloom was monitored visually after three days of storage at 20°C.

Regime 2 (also referred to herein as Cycling Temperature Storage) denotes the sample was stored for seven hours at a temperature of 45°C followed by three days at 20°C and then this temperature cycle was repeated (for a total of two times). At the end of the second cycle the sample was stored for a further eight days at 20°C.

Regime 3 denotes the sample was stored for eight hours at 37°C followed by sixteen hours at 20°C.

Regime 4 denotes the sample was stored in a cabinet, programmed with a temperature cycle for eight hours at 37°C followed by sixteen hours at 20°C. This cycle was repeated for a total of five times and the appearance of bloom was observed at the end of the fifth cycle.

Regime 5 is similar to Regime 1 except the appearance of bloom was monitored after thirteen days of storage at 20°C.

After the specified storage regime the formation of bloom on the surface of the test sample was observed and bloom resistance of the sample was then rated according to one or more of the assessment criteria as described herein. As a control comparison a reference sample (such as Comp A as described herein) may also be assessed for bloom formation after a suitable storage regime such as isothermal storage (Regime 1 ).

The formation of bloom on the test samples was observed and manually rated as described herein and/or by taking pictures of the samples (for example using DigiEye image system).

VISUAL ASSESSMENT OF SAMPLES

Where indicated in some of the tests described herein (e.g. bloom test), the visual appearance of a sample can be assessed before and after the tests as described herein. The appearance can be determined by inspecting the sample surface either manually or for example by taking pictures of the samples using a DigiEye image system (some of the pictures from which are shown in the Figures herein).

In one assessment method the sample appearance may be assessed by measuring what percentage of the sample surface area is unblemished (e.g. by damage, discoloration, haze and/or blooming, as appropriate). In one embodiment of the invention a sample that is deemed acceptable (i.e. passes the test) - assuming before the test the sample is 100% unblemished -, may have a percentage surface area post-test which is substantially unblemished, preferably at least 85%, more preferably at least 90%, even more preferably at least 95%, most preferably at least 99%, for example 100% unblemished

Alternatively or as well the samples herein can also be evaluated visually before and after the test using one or both of the visual rating and/or gloss rating as described below.

The visual rating is used to rate a sample from 5 (best) to 1 (worse) where:

5 is very good, denoting there are no visible signs of blemishes;

4 denotes that blemishes are only slightly visible;

3 denotes there are clearly apparent blemishes;

2 denotes the surface is partially blemished;

1 is very poor, denoting that surface is completely blemished.

Unless otherwise indicated herein a visual rating of 4 or 5 is considered to be a pass and 1 , 2 or 3 a fail.

The gloss rating the surface is placed in one of three categories (B, M or G) to assess bloom resistance where: B denotes a bloomed surface appearance (fail, an unacceptable level of bloom); M denotes a matt surface appearance and G denotes that a glossy surface appearance (M or G showing an acceptable bloom resistance, G being preferred).

STANDARD CONDITIONS

As used herein, unless the context indicates otherwise, standard conditions (e.g. for defining a solid fat or liquid oil) means, atmospheric pressure, a relative humidity of 50% ±5%, ambient temperature (22°C ±2°) and an air flow of less than or equal to 0.1 m/s. Unless otherwise indicated all the tests herein are carried out under standard conditions as defined herein.

SUBSTANTIALLY

The term "substantially" as used herein may refer to a quantity or entity to imply a large amount or proportion thereof. Where it is relevant in the context in which it is used "substantially" can be understood to mean quantitatively (in relation to whatever quantity or entity to which it refers in the context of the description) there comprises an proportion of at least 80%, preferably at least 85%, more preferably at least 90%, most preferably at least 95%, especially at least 98%, for example about 100% of the relevant whole. By analogy the term "substantially-free" may similarly denote that quantity or entity to which it refers comprises no more than 20%, preferably no more than 15%, more preferably no more than 10%, most preferably no more than 5%, especially no more than 2%, for example about 0% of the relevant whole. Preferably where appropriate (for example in amounts of ingredient) such percentages are by weight.

The invention is illustrated by the following non-limiting Figure 1 herein, where:

Figure 1 is a DSC thermograph of Example 1 and Comp A, generated as described in the examples herein.

It should be noted that embodiments and features described in the context of one of the aspects or embodiments of the present invention also apply to the other aspects of the invention. Although embodiments have been disclosed in the description with reference to specific examples, it will be recognized that the invention is not limited to those embodiments. Various modifications may become apparent to those of ordinary skill in the art and may be acquired from practice of the invention and such variations are contemplated within the broad scope of the present invention. It will be understood that the materials used and the chemical details may be slightly different or modified from the descriptions without departing from the methods and compositions disclosed and taught by the present invention.

Further aspects of the invention and preferred features thereof are given in the claims herein.

As used in this specification, the words "comprises", "comprising", and similar words, are not to be interpreted in an exclusive or exhaustive sense. In other words, they are intended to mean "including", but not limited to.

Any reference to prior art documents in this specification is not to be considered an admission that such prior art is widely known or forms part of the common general knowledge in the field.

The invention is further described with reference to the following examples. It will be appreciated that the invention as claimed is not intended to be limited in any way by these examples. It should be appreciated that variations and modifications may be made without departing from the scope of the invention as defined in the claims. Furthermore, where known equivalents exist to specific features, such equivalents are incorporated as if specifically referred in this specification.

Examples

The present invention will now be described in detail with reference to the following non limiting examples which are by way of illustration only.

Example 1 and Comp A :

Two chocolate compositions were prepared with the same ingredients, except that Example 1 (of the invention) contains silica oxide particles having a size of 7 nanometres, while Comp A (a control) does not contain silica oxide particles but contains molten milk fat.

The chocolate compositions are shown in Table 1 below (expressed in weight parts):

Table 1

Chocolate mass preparation:

Molten cocoa butter was weighed. In Comp A, molten milk fat was added and mixing was performed until a homogenous mixture was obtained. In Example 1 , silica oxide particles (Aerosil A380) were added and mixing was performed using a Silverson L4R mixer at 5000rpm for 10 min at 50°C. Soy lecithin was added and mixing was performed until a homogenous mixture was obtained. Skimmed milk powder, cocoa powder and sugar were added and mixed until a homogeneous mass was obtained

Chocolate Mass Tempering

Chocolate mass was tempered manually by on a marble table by a confectioner skilled in the art. The hand tempering method is described by S Beckett in The Science of Chocolate, 2 ^nd Ed (2008) RSC Publishing, p 128. After tempering, the chocolate mass was molded and placed in the fridge for setting. After setting the chocolate pieces were unmolded, packed in plastic bags and stored at 20°C.

Assessment of chocolate stability The following DSC program was used to assess the chocolate stability of each sample. The sample (accurately about 1.3mg) was loaded at 15°C and equilibrated for 5 min. The sample was then cooled down rapidly to -30°C and maintained at this temperature for 10 min. A rapid heating was applied to the sample to 37°C before the sample was cooled back down to -30°C. The sample was maintained at -30°C for 10 min before melting to 70°C to develop a melt thermograph. The thermographs generated are shown in Figure 1 .

The DSC thermographs show that the control sample Comp A (dotted line in Fig 1 ) lost most of its temper after exposure to 37°C as indicated by the area of the higher melting peak. On the contrary, Example 1 of the invention (solid line in Fig 1 ) shows a significant proportion of high melting crystals.