HK1126355B - Natural stabiliser system for frozen dessert - Google Patents

Description

Field of the invention

The present invention relates to stabiliser systems which may be used in the manufacture of frozen dessert which comprise native rice starch egg yolk as a natural emulsifier and citrus fibres. It also relates to a method for manufacturing a frozen confectionery using a stabiliser system that contains only natural ingredients. The invention, in another aspect, also concerns the frozen confectionery products thus produced.

Background of the invention

In the manufacture of frozen confectionery, stabilisers are generally used for functional purposes such as improvement of smoothness, prevention of ice crystal formation in storage, improvement of handling properties, while the use of emulsifiers results in smaller air cells which are evenly distributed in the product.

These ingredients are indispensable to the manufacture of commercially acceptable products. Efficient stabiliser/emulsifier systems already exist, but these are often chemically modified products. There is thus a need for providing systems which are more natural and efficient. There have been some efforts in this field.

For instance WO2005/115163 describes the use of vegetable fibres which are more effective to maintain the compactness and structural resistance of similar products that use stabilisers like guar, carob, alginates, carrageenan and others.

EP 1180330 A1 proposes to replace the traditional use of expensive stabilising agents without compromising the organoleptic properties of frozen confectionery. To this end, it is proposed a frozen confectionery comprising fat, a sweetening agent, milk solids non fat, water, starch such that the total amount of starch and milk solids non fat is between 2.5 and 18% and that the weight ratio of starch to milk solids non fat is between 0.03 and 1.5.

Starch, in particular rice starch and/or oat starch, is also present in the composition of WO92/13465 as a fat substitute in frozen desserts. The dessert are said to have an excellent texture, smoothness and mouth feel. Similarly, CN1403008 also discloses the use of rice starch as fat substitute and JP3209714 discloses the preparation of a liquid base for ice cream also comprising rice starch.

EP 1400176 A1 also describes frozen aerated products which have no additional stabilisers or emulsifiers and have an overrun of 10-250%, a pH, when melted, of 3.5 to 5.2, and which comprise 0-20% fat, 0.25 to 20% milk solids not fat, 0.05 to 1.5% soluble dietary fibre and 0.1 to 5% insoluble dietary fibres.

WO 9115517 relates to low-cost crude pectin-containing vegetable product prepared from agricultural waste products which can be useful as a stabilizer for frozen desserts. The raw material may be used directly as it is obtained from the fruit or vegetable processing plants. Especially preferred sources of raw materials for the product are citrus fruit peel, apple pomace and sugar beet pulp.

Stabiliser systems are widely available on the market. These generally include gums, esters of mono-, diglycerides, etc. and are thus mostly not considered as fully natural products.

GB 2359727 also describes an emulsifier composition which be used in ice creams and which comprises an emulsifier which encapsulates a disintegration improver, such as a fibre or a hydrocolloid.

EP-A-0153870 , US-A-5234706 , EP-A-0480665 , US-B1-6395314 , EP-A-1563744 , and WO 2006/134584 disclose frozen confectionery products or compositions used for frozen confectionery products comprising native rice starch and vegetable fibers.

Janvary L.: "Possible uses of functional ingredients in ice cream targeting the wellness market." European Daily Magazine, 2006, pages 28-30 discloses frozen confectionery products (e.g. fat reduced ice cream) comprising native rice starch (nutrits) and vegetable fibers (Beneo: chicory oligofructose), in combination and both as stabilizer.

Object of the invention

There thus still remains a need to provide a stabiliser system which can be used in the manufacture of all natural frozen confectionery products. There is also a need for efficient stabiliser systems.

Summary of the invention

Accordingly, the present object is achieved by means of the features of the independent claims. The dependent claims develop further the central idea of the invention.

Accordingly, in a first aspect, the present invention provides a stabiliser system for use in frozen confectionery, characterised in that it comprises native rice starch egg yolk as a natural emulsifier and citrus fibres.

The use of a stabiliser system according to any of claims 1 to 5 in the manufacture of frozen confectionery also forms part of the invention.

In a further aspect, a method for the manufacture of a frozen confectionery comprising the steps of:

• a. Blending frozen confectionery ingredients with a stabiliser system comprising native rice starch, egg yolk and citrus fibres,
• b. Pasteurising the mix,
• c. Homogenising the ice cream mix in at least one stage at a pressure of 150-250bars, preferably 180-250bars, more preferably 200-230bars, and in a second stage at pressures between 10-20 bars,
• d. Freezing the mix

as well as a product obtainable by said method are provided by the present invention.

Finally, a frozen confectionery product characterised in that it comprises native rice starch, egg yolk as a natural emulsifier and expanded citrus fibres is also encompassed by the present invention.

Detailed description of the invention

The present invention concerns a stabiliser system for use in frozen confectionery. By "stabiliser system" is to be understood a mixture of ingredients, which contribute to the stability of the frozen product with respect to ice crystal formation, heat shock resistance, overall texture properties etc. Thus the stabiliser system may comprise any ingredients which are of structural importance to the frozen confectionery. This stabiliser system may thus comprise ingredients which render the texture creamier, or emulsifying ingredients, which overall contribute to the advantageous textural, structural, organoleptic properties of the product.

In the present description, by "natural ingredients" is meant ingredients of natural origin. These include ingredients which come directly from the field, the animals etc. They may also include ingredients which are the result of a physical or microbiological/enzymatic process (e.g. extraction, fermentation etc.). However, they do not include ingredients which are the result of a chemical modification process.

In the present invention, the stabiliser system is characterised in that it comprises native rice starch, egg yolk as a natural emulsifier and citrus fibres.

By fruit fibres is to be understood fibres obtainable by any fruit or mixtures of fruits. They may be provided in the form of pieces of the fruit itself, fruit extracts, fruit juice, fruit puree, fruit concentrate etc. Suitable fruits include apple, lemon, banana, blackberry, blackcurrant, blueberry, cherry, pomegranate, pumpkin, cranberry, gooseberry, grapes, guava, kiwi, mango, orange, papaya, passion fruit, peach, pear, pineapple, plums, raspberry, redcurrant, strawberry, tomato, etc.

By vegetable fibres is to be understood fibres obtainable by any plant source other than a fruit. These may include beans, Brussels sprouts, carrot, cauliflower, celery, onions, sugar beet, potato, cabbage etc.

The fibres used in the present invention are citrus fibres.

By native rice starch is meant rice starch which has not undergone any chemical or physical modifications.

Without wishing to be bound by theory, it is suspected that the combination of fibres from vegetables, fruits, or mixtures thereof and native rice starch is particularly effective as a stabiliser.

Additionally, native rice starch has been shown to give better results than other starches (e.g. tapioca starch or maize starch) in terms of global texture and creaminess.

Furthermore, the stabiliser system presents the advantage that it does not contain any artificial or unnatural components.

The ratio of native rice starch to fibres in the stabiliser system of the invention is 1:1 up to 10:1, preferably 1:1 up to 6:1, most preferably the ratio is 2:1.

According to the present invention, the natural emulsifier used is egg yolk.

By emulsifier is meant compounds which confer to the finished product a smoother texture and stiffer body, which reduce the whipping time. The presence of emulsifiers results in air cells that are smaller and more evenly distributed throughout the internal structure of the ice cream.

In a most preferred embodiment, the stabiliser system comprises native rice starch, citrus fibres and egg yolk only.

The stabiliser system of the invention may be used in the manufacture of frozen confectionery. For example, it may be used in the same way as traditional stabiliser/emulsifier systems in the manufacture of ice cream, sorbet, mellorine etc. It presents not only the advantage of being particularly effective, but also the advantage that it contains only natural ingredients and can be used in green label, all natural frozen confectionery.

The invention further relates to a method for the manufacture of a frozen confectionery comprising, in a first stage, the step of blending frozen confectionery ingredients with a stabiliser system comprising native rice starch, citrus fibres and egg yolk.

Frozen confectionery ingredients are typical ingredients such as any of fat, sugars, milk solids non-fat and combinations thereof. In an embodiment, the ingredients do not contain any fat. In another embodiment, if fat is used, it is present in an amount of 5-20%, preferably 8-15%, more preferably 10-13%.

Once the above ingredients are mixed, the mix is pasteurised under standard conditions. The following homogenisation step is carried out in a first stage at a pressure of 150-250bars, preferably 180-250bars, more preferably 200-230bars and in a second stage at pressures between 10-80bars.

In a final step, the mix is frozen. The freezing step preferably is done in two steps: firstly, 10-60 minutes in a blast freezer at -35°C and then at least 2-3 hours at - 16°C.

Preferably, prior to freezing, the mix may be aged under standard conditions and packaged into containers of desired dimensions and hardened.

Optionally, the addition of flavourings, colourings, sauces, inclusions etc. may be carried out prior to the ageing step. If flavourings, colourings, sauces, inclusions etc. are added, these are selected from natural ingredients only.

In a preferred embodiment, the frozen confectionery is aerated to an overrun of 20-80%, preferably 30-60%.

The method of the invention thus lends itself to the manufacture of frozen confectionery which are all natural and do not contain any artificial ingredients, "E-numbers" etc. Furthermore, it is surprising that the high pressure homogenisation used in the present method to activate the fibres is compatible with the presence of native rice starch and, also optionally, the presence of high amounts of fat (up to 15%). Under standard manufacturing conditions, it would not be contemplated to combine high amounts of fat with the high homogenisation pressure. Furthermore, starch is normally sensitive to high pressures. However, the present invention has found that the present manufacturing conditions surprisingly produce stable products and products which have good creaminess properties.

Also, using the present stabiliser system in the production of sorbet (i.e. no or low fat content), allows to manufacture a sorbet with additional creaminess perception.

The products obtainable by the present method also form part of the invention.

A further aspect of the invention relates to frozen confectionery comprising native rice starch, egg yolk as a natural emulsifier and expanded citrus fibres.

Expanded fibres are fibres which have undergone an "activation" step, for example by high energy processing of the fibres in a solvent. Such high energy processing may be high pressure homogenisation and/or high shear mixing. Thus, the three-dimensional structure of the fibres is modified in that the surface area of the fibres is increased. Expanded fibres, i.e. fibres with higher surface area provide improved functionality and confer better thickening properties, freeze-thaw, heat and/or foam stability etc. to the compositions in which they are present.

The expanded fibres present in the frozen confectionery are expanded citrus fibres.

The frozen confectionery may be an ice cream or a sorbet and may have an overrun of 20 to 100%, preferably 20 to 80%, more preferably 30 to 60%.

In an embodiment, the fat content of the present frozen confectionery is 5-20%, preferably 8-15%, more preferably 10-13%, while in another embodiment, the fat content may be lower than 5%, down to 0%.

The rice starch is preferably present in an amount of 0.1-3%, preferably 0.2-2% of the frozen confectionery.

The fibres in the frozen confectionery may be present in an amount of 0.05-2%, preferably 0.1-0.8% of the frozen confectionery.

The present confectionery are characterised in that they comprise only natural ingredients.

The present invention proposes a new way in which an "all natural" frozen confectionery which is stable and organoleptically acceptable by the consumer may be manufactured without resorting to artificial ingredients. Standard stabiliser/emulsifier systems which comprise "e-numbers" or chemically synthesised compounds are dispensed with, which provides a more appealable product to the consumer. Furthermore, organoleptic aspects such as creaminess are not compromised despite the high energy processing conditions, not normally used in frozen confectionery manufacture.

The present invention is illustrated further herein by the following non-limiting examples.

Examples Example 1

An ice cream of the invention was manufactured under the following conditions:

• Sugar, milk fat, MSNF, native rice starch and citrus fibres were blended with water using a high speed blender. The mix was then pasteurised under continuous pasteurisation using a high temperature short time (HTST) heat exchanger in a large, insulated feed tank, with preheating to 30-40°C. Pasteurisation was carried out, followed by homogenisation in two stages, firstly at above 180 bars and, in the second stage, at 50 bars. Flavours, colourings, inclusions, sauces could be added to the mix. The mix was then aged for 6 hours at 3°C before being packed in boxes. The ice cream was then hardened at -35°C, followed by -16°C and then stored at -18°C.

Example 2

An ice cream recipe having an overrun between 20-80% according to the present invention is given below:

Fat	8-15
Sugar	17-24
MSNF	8-12
Egg yolk	1.5-3
Rice starch	0.2-1
Citrus fibres	0.1-0.6
Total solids	38-48

Example 3

A sorbet recipe having an overrun between 20-80% according to the present invention is given below:

Sugar	30-38
Rice starch	1.2-2
Citrus fibres	0.2-0.7
Total solids	31-41

Claims (14)

1. stabiliser system of natural ingredients for use in frozen confectionery characterised in that it comprises native rice starch, egg yolk as a natural emulsifier and citrus fibres.
2. Use of a stabiliser system according to claim 1 in the manufacture of frozen confectionery.
3. Method for the manufacture of a frozen confectionery comprising the steps of:

   a. Blending frozen confectionery ingredients with a stabiliser system of natural ingredients comprising native rice starch, egg yolk and citrus fibres,

   b. Pasteurising the mix,

   c. Homogenising the ice cream mix in a first stage at a pressure of 150-250bars, preferably 180-250bars, more preferably 200-230bars and in a second stage at pressures between 10-80 bars,

   d. Freezing the mix.
4. Method according to claim 3, wherein the frozen confectionery ingredients include any of fat, sugars, milk-solids non-fat and combinations thereof.
5. Method according to claim 4, wherein the fat is present in an amount of 5-20%, preferably 8-15%, more preferably 10-13%.
6. Method according to claim 4, wherein the frozen confectionery ingredients do not include fat.
7. Method according to any of claims 3 to 6, which comprises an additional ageing step and a packaging step prior to freezing the mix.
8. Frozen confectionery product characterised in that it comprises native rice starch, egg yolk as a natural emulsifier and expanded citrus fibers.
9. Frozen confectionery product according to claim 8, which is an ice cream or a sorbet.
10. Frozen confectionery product according to any of claims 8 or 9, which has an overrun of 20 to 100%, preferably 20 to 80%, more preferably 30 to 60%.
11. Frozen confectionery product according to any of claims 8 to 10, which has a fat content of 5-20%, preferably 8-15%, more preferably 10-13%.
12. Frozen confectionery product according to any of claims 8 to 10, which has a fat content lower than 5%, down to 0%.
13. Frozen confectionery product according to any of claims 8 to 12, which comprises native rice starch in an amount of 0.2-2% and citrus fibres in an amount of 0.1-0.8% of the frozen product.
14. Frozen confectionery product according to any of claims 8 to 13, which comprises only natural ingredients.