Low fat chocolate

Abstract

The application describes comestible products comprising a water-in-oil emulsion, the water-in-oil emulsion comprising cocoa butter and a fat-crystal stabilised aqueous phase dispersed substantially through the cocoa butter continuous phase and optionally one or more additional ingredients of chocolate. Hydrocolloids, such as gelative or carrageenan are typically used to stabilise the aqueous phase. Methods of making comestible products are also provided.

Claims

1. A comestible product comprising a water-in-oil emulsion, the water-in-oil emulsion comprising cocoa butter type V fat-crystal stabilized particles encapsulating an aqueous phase, the type V fat-crystal stabilized particles being dispersed substantially through the cocoa butter continuous phase and one or more additional ingredients of chocolate, wherein the comestible product is made by a method in which cocoa butter is heated, optionally with an emulsifier, and mixed to form a heated mixture, and wherein the heated mixture is cooled to a temperature in the range of about 20° C. to about 30° C. to allow the type V fat-crystal stabilized particles to form.

2. A comestible product according to claim 1, wherein the aqueous phase contains hydrocolloid.

3. A comestible product according to claim 2, wherein the hydrocolloid comprises gelatine or carageenan.

4. A comestible product according to claim 1, wherein the continuous phase comprises vegetable fats.

5. A comestible product according to claim 1 which is chocolate.

6. A comestible product according to claim 1, wherein the aqueous phase comprises 70%-98%, by weight water and 2%-30% by weight of hydrocolloid.

7. A comestible product according to claim 1 comprising polyglycerol polyricinoleate (PGPR) emulsifier.

8. A comestible product according to claim 1, additionally comprising within the water-in-oil emulsion one or more additional components selected from sugar, milk powder, sweeteners, cocoa powder, flavourings, fruits, nuts, biscuit particles, candy particles and colourings.

9. A comestible product according to claim 1, wherein the type V crystals allow formation of the fat-crystal stabilized particles encapsulating the aqueous phase.

10. a comestible product according to claim 1, wherein the type V crystals allow the comestible product to be maintained at a temperature below the melting point of cocoa butter fat crystals for transportation without any deterioration in stability of the water-in-oil emulsion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will now be described by way of example only with reference to the following figures:

(2) FIG. 1 is a schematic diagram of the process for producing the water-in-oil cocoa butter emulsion.

(3) FIG. 2 is a graph showing Differential Scanning Calorimetry measurements of melting temperature for a chocolate product of the invention

(4) FIG. 3 show an SEM micrograph of fat crystal shells surrounding a water particle in a chocolate product.

DETAILED DESCRIPTION OF THE INVENTION

(5) FIG. 1 shows a schematic diagram of the equipment used to produce the water-in-oil cocoa butter emulsion. A heated cocoa butter and polyglycerol polyricinoleate emulsifier (PGPR) mixture 10 is added to the heated aqueous phase comprising water and hydrocolloid 11 and then stirred using an overhead stirrer 12 for a period of approximately 5 minutes until the mixture is homogeneous. The cocoa butter and PGPR mixture was heated using a water bath (not shown) to a temperature of 60° C. in order to melt all six forms of cocoa butter crystals and this temperature was maintained during mixing with the aqueous phase. This pre-emulsion mixture is then pumped through the margarine line 13.

(6) The margarine line 13 comprises a scrape surface heat exchanger (A Unit) and pin stirrer (C Unit). The margarine line is a continuous process in which the temperature of the two jackets can be manipulated so that tempering can occur during the emulsification stage through the control of shear and temperature.

(7) The scrape surface heat exchanger was kept at 20 degrees C., which allowed the cocoa butter to cool to approximately 25 degrees C., allowing crystal types IV and V to form. The pin stirrer is kept at 30 degrees C. to melt any type IV crystals, leaving just type V crystals. Both the scrape surface heat exchanger and pin stirrer are fitted with water baths (not shown) so the temperature can be altered to optimise the resulting chocolate product that is tempered.

(8) The resulting water-in-oil cocoa butter emulsion 14 then has sugar or other further ingredients added for the production of chocolate. These further ingredients are added by a suitable stirring process and can include but are not limited to sugar, milk powder and cocoa powder.

(9) In certain varieties of chocolate additional ingredients might be required, such as sweeteners, flavourings, fruit, nuts and/or biscuit particles. The sweeteners and flavourings can be added to the aqueous phase and/or the cocoa butter emulsion and/or the chocolate mixture.

(10) The chocolate mixture is then poured into the required shapes before cooling, removal from the mould and wrapping for storage and retail distribution. Alternatively, the mixture can be transferred to a sealable storage container in which it can be cooled and stored under refrigerated conditions for later use.

(11) If necessary, the chocolate can be maintained at a temperature below the melting point of the cocoa butter fat crystals for transportation without any deterioration in the stability of the water-in-oil emulsion.

(12) The sugar, milk powder and cocoa powder are selected with a particle size that gives the required texture in the chocolate. If the particle sizes are too large the chocolate will have a gritty texture. Smaller particle sizes result in a smoother texture.

(13) Cocoa butter is known to have at least five crystal forms, each of which have different melting points. Although the thermodynamically stable form is Form VI, consumers find Form V (β.sub.2) the most attractive, as it melts between 32 and 34° C. (mouth temperature). Furthermore, the Form V fat crystal network allows chocolate to snap, and provides the glossy appearance preferred by consumers.

(14) Scanning Electron Microscope images (FIG. 3) showing fat crystal shells in a chocolate product. The fat crystal shells surround the water and hydrocolloid to retain the water inside the shell 21, thereby osmotically separating the water from other ingredients in the chocolate.

EXAMPLE 1

(15) Firstly a cocoa butter emulsion was made comprising 20% aqueous phase (made up of 10% gelatine and 90% water) and 80% lipid phase (made up of 96% cocoa butter and 4% polyglycerol polyricinoleate (PGPR)). The water used to make up the aqueous phase was distilled water. The source of the gelatine was porcine skin (Fluka) and was a high gel strength grade (250 g bloom). The cocoa butter used was a commercial grade. The PGPR was supplied by Kerry Bio-Science.

(16) The cocoa butter and PGPR were heated together using a water bath to a temperature of 60 degrees C., in order to melt all six forms of cocoa butter crystals. The gelatine was dissolved in the water using a magnetic heater-stirrer. The aqueous phase was then added to the cocoa butter and PGPR mixture and stirred for 5 minutes using an over-head stirrer fitted with an anchor head until the mixture looked homogeneous. This pre-emulsion was then pumped through a bench-top margarine line comprising a scrape surface heat exchanger followed by a pin stirrer. Both the scrape surface heat exchanger and pin stirrer units are fitted with water baths so temperature of each unit can be altered to result in a chocolate product that is tempered.

(17) Further ingredients required for the chocolate were then added to the emulsion and mixed by stirring to give a homogeneous mixture with the following composition:

(18) TABLE-US-00001 Cocoa butter emulsion 30% Sugar 35% Milk Powder 28% Cocoa Powder  7%

(19) The ingredients selected for this example were readily available commercial products. The sugar was Silver Spoon icing sugar (ingredients icing sugar and tricalcium phosphate) from Silver Spoon Ltd. UK. The milk powder was Marvel Original Dried Skimmed Milk Powder (ingredients dried skimmed milk 99.5% and vitamins A & D) from Premier Foods Ltd. The cocoa powder used was Cadbury Bournville Cocoa (ingredients cocoa powder) from Cadbury Ltd. Bournville, Birmingham, UK.

(20) After mixing the bulk of the chocolate mixture was transferred to a sealable storage container for storage in a refrigerator. After a period of 2 months the chocolate showed no sign of bloom formation, indicating that no migration of the water content had taken place.

(21) A sample of the chocolate was taken for melting point determination using Differential Scanning Calorimetry (DSC). The results for the DSC test are shown in FIG. 2 and indicate that the example chocolate with gelatine had a melting point close to that of a popular commercial brand (“Cadbury Dairy Milk, Cadbury Ltd. Bourneville, Birmingham, UK), an important feature for mouth feel in such products.

EXAMPLE 2

(22) A low calorie chocolate was made by first making a water in cocoa butter emulsion with a water content of 20%

(23) To make the water in cocoa butter emulsion an aqueous phase was made by adding 2% gelatin to 98 g of distilled water. The distilled water was heated to 60° C. and the gelatin was dissolved in the water using a magnetic heater-stirrer and slowly adding the gelatin while the mixture was stirred. The source of the gelatin was porcine skin (Fluka) and was a high gel strength grade (250 g bloom)

(24) A fat phase was made up of cocoa liquor (52% cocoa butter and 48% cocoa solids) and 1% PolyGlycerol PolyRicinoleate (PGPR) dispersed through the mixture. This fat phase was heated to 60° C. using a water bath and a cocoa butter emulsion was prepared by adding the aqueous phase to the fat phase mixture and stirred for 5 minutes to produce a pre-emulsion using an over-head stirrer fitted with an anchor head until the mixture looked homogeneous.

(25) The pre-emulsion was then emulsified in a high shear mixer (Silverson L4RT, 5000 rpm, 5 mins) to produce a fine water-in-oil emulsion with water droplets with a size of approximately 3 μm.

(26) The emulsion mixture was then mixed with sugar at 27° C. to produce a full chocolate and cooled to room temperature or 5° C. The sample was checked using a DSC and was found to be tempered with a Form V fat crystal network structure for the cocoa butter corresponding to a melting point of 32° C. for an acceptable mouth feel. The resulting chocolate was found to have a glossy surface appearance and snapped as expected for a dark chocolate.

EXAMPLE 3

(27) Example 2 was repeated but the emulsification process was carried out in a scrape surface heat exchanger (SSHE) and a pin stirrer at temperatures of 20° C. and 27° C. respectively. This resulted in a water droplet size of 2 μm to 3 μm. The resulting emulsion was then mixed with icing sugar at 27° C. in a 50:50 ratio by weight to produce a full chocolate before cooling to room temperature.

(28) The resulting dark chocolate was glossy and snapped, with an effective 12% calorie reduction.

EXAMPLE 4

(29) Example 3 was repeated with a ratio of water to cocoa liquor of 40% to 60%. The droplet size obtained was in the range 3 μm to 4 μm. The resulting emulsion was mixed with milled sugar in a 50:50 mixture to produce a full chocolate. The mixture was cooled to room temperature or 5° C. Again, the desired Form V fat crystal network structure with a melting temperature of 32 C was produced and the chocolate was glossy and snapped.

(30) The resulting dark chocolate was glossy and snapped, with an effective 24 to 36% calorie reduction.

EXAMPLE 5

(31) Example 2 was repeated but instead of using gelatin in the aqueous phase no hydrocolloid was added.

(32) It was found that the resulting chocolate was glossy but did not snap as well as the samples containing a hydrocolloid.

EXAMPLE 6

(33) Example 2 was repeated with the aqueous phase containing 0.5% kappa carrageenan as a replacement for the gelatin. Macro and micro structural properties were similar to that of example 2.

EXAMPLE 7

(34) Example 6 was repeated with the aqueous phase containing 0.5% iota carrageenan as a replacement for the kappa carrageenan. Macro and micro structural properties were similar to that of example 2.

EXAMPLE 8

(35) Example 3 was repeated in which the gelatin in the aqueous phase was replaced with 0.5% kappa carrageenan. Macro and micro structural properties were similar to that of example 3.