WO1996019114A1

WO1996019114A1 - A method for preparing an edible water-in-oil emulsion

Info

Publication number: WO1996019114A1
Application number: PCT/IE1994/000061
Authority: WO
Inventors: John Maguire; Joseph Patrick Mcauliffe
Original assignee: Charleville Research Limited
Priority date: 1993-07-02
Filing date: 1994-12-22
Publication date: 1996-06-27
Also published as: GB2280449A; GB2280449B; GB9413405D0

Abstract

A spread is prepared from a water-in-oil emulsion, which is prepared using a margarine process, in which the fat phase of the emulsion comprises unhydrogenated fish oil containing an antioxidant blend of ascorbyl palmitate. The aqueous phase of the emulsion is prepared without ingredients or additives which may react with, or act as a catalyst for a reaction with the unhydrogenated fish oil or the ascorbyl palmitate to at least retard the development of a metallic type off-flavour or fishy taste. The aqueous phase is prepared with de-ionised water having a very low calcium content, and a sequestrant is provided for binding metal ions. Milk protein containing ingredients are excluded from the aqueous phase.

Description

"A method for preparing an edible water-in-oil emulsion"

The present invention relates to a method for preparing an edible water-in-oil emulsion containing unhydrogenated fish oil. The invention also relates to the water-in-oil emulsion containing the unhydrogenated fish oil prepared by the method and to a spread prepared from the water-in-oil emulsion.

Fish oil has very significant and desirable nutritional properties. It is also relatively high in omega-3 polyunsaturated fatty acids, which have been found to play a significant role in the prevention, or at least reduction in the incidence of heart disease. However, fish oil suffers from a serious disadvantage in that it deteriorates at a relatively rapid rate. To arrest the relatively rapid deterioration of fish oil, the fish oil is subjected to various processes, and in particular, the fish oil is hydrogeπated. However, the hydrogenation process significantly reduces the omega-3 polyunsaturated fatty acids content, thereby significantly reducing the beneficial health effects of the fish oil, and in particular, its beneficial effects in the prevention and/or at least reduction in the incidents of heart disease. Therefore, in order to avoid a reduction in the omega-3 polyunsaturated fatty acids content, it is important that the fish oil should be unhydrogenated. It is known from European Patent Specification No. 0,304,115A that by blending unhydrogenated fish oil with vegetable oil during or shortly after refining and deodorising of the fish oil, a fat blend can be prepared which has a reasonable shelf life. Although, in general, it has been found that the unhydrogenated fish oil should be stabilised with an antioxidant prior to being blended with the vegetable oil. The antioxidant may be natural or synthetic, and typically may be ascorbyl palmitate. However, where such a fat blend is to be used to form a water-in-oil emulsion which would be suitable as a spread for spreading on bread and the like, and which should be firm at room temperature, the fat phase of such emulsions, typically, contain a hard stock fat, which may be a butter fat, and the aqueous phase, in general, contains various dairy ingredients.

It has, however, been found that water-in-oil emulsions containing unhydrogenated fish oil which have been treated with an antioxidant, when prepared in the form of a spread firm at room temperature develop a metallic off-type flavour which is often described as a fishy taste.

There is therefore a need for a method for preparing an edible water-in-oil emulsion containing unhydrogenated fish oil and an antioxidant in which the development of such a metallic type off- flavour and/or fishy taste is avoided, or at least if not avoided is retarded to provide a water-in-oil emulsion with a reasonable shelf life. There is also a need for such an edible water-in-oil emulsion.

The present invention is directed towards providing such a method and an edible water-in-oil emulsion.

According to the invention there is provided a method for preparing an edible water-in-oil emulsion containing unhydrogenated fish oil, the water-in-oil emulsion comprising a fat phase and an aqueous phase, the fat phase comprising unhydrogenated fish oil containing an antioxidant, wherein the aqueous phase is prepared without ingredients or additives which may react with, or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste, and thereby, at least retard the development of a metallic type off-flavour or fishy taste.

The advantages of the invention are many. It has been found that edible food products, for example, spreads, a bread shortening product and the like which have been prepared from the water-in- oil emulsion of the invention have a reasonable shelf life, typically, 16 weeks at 10°C. In general, during this shelf life virtually no deterioration of the product takes place. The products are free from any metallic type off-flavour or fishy taste. It is believed that any adverse reaction with the unhydrogenated fish oil which contains the antioxidant may take place with the antioxidant, and accordingly, it is believed advisable that the aqueous phase should be prepared without ingredients or additives which may react with or may act as a catalyst for reaction with the antioxidant to cause such a metallic type off-flavour or fishy taste. Additionally, the aqueous phase is prepared without ingredients or additives which would react with or would act as a catalyst for a reaction with a constituent ingredient of the antioxidant and/or an antioxidant blend. Where the unhydrogenated fish oil comprises an antioxidant or an antioxidant blend which is or includes ascorbyl palmitate, the aqueous phase is preferably prepared without ingredients or additives which would react with or would act as a catalyst for a reaction with the ascorbyl palmitate.

It is believed that milk proteins containing ingredients may react with or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the metallic type off-flavour or fishy taste. Accordingly, it is desirable that the aqueous phase should be prepared so that milk protein containing ingredients in any significant amounts are excluded from the aqueous phase, and preferably, milk protein containing ingredients should be entirely excluded from the aqueous phase. In particular, it is believed that any one or more of the following ingredients may react with or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the metallic type off-flavour or fishy taste: whey, whey powder, skimmed milk, skimmed milk powder, butter milk, butter milk powder, whole milk, whole milk powder, and sodium caseinate.

Accordingly, it is advisable to prepare the aqueous phase so that any one, and preferably, all the above ingredients and/or additives in any significant amounts are excluded from the aqueous phase, thereby, at least retarding, and in general, preventing the development of the metallic type off-flavour or fishy taste. Ideally, the aqueous phase is prepared so that all the above ingredients are excluded from the aqueous phase.

It is also believed that metals and trace metals in the aqueous phase may react with or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the metallic type off-flavour and/or fishy taste, and accordingly, it is advisable that the aqueous phase be prepared with de-ionised water. To further minimise the development of the metallic type off-flavour and/or fishy taste, it is preferable that a sequestrant should be added to the aqueous phase for binding metal ions therein. Any one or more of the following have been found to be suitable sequestrants: citric acid and/or its salts, phosphate salts, and ethylene diamine tetra-acetic acid and/or its salts.

It is also believed that calcium in the aqueous phase may compete for sequestration with the undesirable metal ions, thereby reducing the effectiveness of the sequestrant and causing the metallic type off-flavour and/or fishy taste, and accordingly, it is preferable that the aqueous phase should be prepared with a relatively low calcium content, and preferably, a very low calcium content. Ideally, the water of the aqueous phase should have a relatively low, and preferably, a very low calcium content. It is preferable that the calcium content of the aqueous phase should be less than twenty parts per million parts of the aqueous phase, and advantageously, the calcium content of the aqueous phase should be less than ten parts per million, and ideally, the calcium content of the aqueous phase should be less than five parts per million.

The fat phase of the water-in-oil emulsion may constitute up to 95% by weight of the water-in-oil emulsion. Although, normally, the fat phase would not constitute more than 82% by weight of the water-in-oil emulsion. More commonly, the fat phase would constitute up to 60% by weight of the water-in-oil emulsion, and in low fat emulsions which are suitable as low fat spreads, the fat phase would typically constitute approximately 40% by weight of the water-in-oil emulsion. The unhydrogenated fish oil containing the antioxidant may constitute up to 50% by weight of the water-in-oil emulsion, but generally would constitute up to 40% by weight of the water-in- oil emulsion. More typically, the unhydrogenated fish oil containing the antioxidant would not constitute more than 30% by weight of the water-in-oil emulsion, and preferably, the unhydrogenated fish oil containing the antioxidant constitutes between 3% and 20% by weight of the water-in-oil emulsion. In cases where the water-in-oil emulsion is for use as a spread, the unhydrogenated fish oil containing the antioxidant may typically constitute approximately 4% by weight of the water-in-oil emulsion. Good results have been achieved by using an unhydrogenated fish oil sold by Roche Products Limited of Great Britain under the Trade Mark R0PUFA "30" n-3 EPA Oil.

It is preferable that the fat phase comprises at least one vegetable oil, and at least one of the vegetable oils should preferably be liquid at room temperature. Any suitable vegetable oil may be used, however, the following vegetable oils have been found to be particularly suitable: rape seed oil , soya bean oil , sun flower oil , and olive oil .

In the preparation of a water-in-oil emulsion which is to be prepared as a spread, the fat phase should comprise a hard stock fat which is firm at room temperature. Ideally, though not essentially, the hard stock fat should be a vegetable oil, and any suitable vegetable oil may be used, although good results have been achieved by selecting the hard stock fat from any one or more of the following hard stock vegetable oils: hydrogenated or partly hydrogenated soya bean oil, hydrogenated or partly hydrogenated rape seed oil, hydrogenated or partly hydrogenated palm oil, hydrogenated or partly hydrogenated coconut oil, hydrogenated or partly hydrogenated palm kernel oil, and a vegetable oil naturally hard at room temperature, for example, coconut oil, palm kernel oil, palm oil and fractions thereof.

The hard stock fat may also be provided by an animal fat, for example, milk fat, tallow, lard and fractions thereof, and/or may be a combination of one or more animal fats and one or more vegetable fats.

The fat phase should ideally contain an emulsifier, and a suitable emulsifier is a mono and/or diglyceride of fatty acids. Typically, the water-in-oil emulsion may contain a colouring, a flavouring and/or vitamins. The aqueous phase may typically contain lactic acid, non-milk proteins and/or flavouring additives. Preferably, the aqueous phase should also include a stabiliser, salt and a preservative, such stabilisers and preservatives will be well known to those skilled in the art. While the water-in-oil emulsion may be prepared using any suitable method, emulsions prepared using a margarine process have been demonstrated to provide good results.

Additionally, the invention provides an edible water-in-oil emulsion containing unhydrogenated fish oil, the water-in-oil emulsion comprising a fat phase and an aqueous phase, the fat phase comprising unhydrogenated fish oil containing an antioxidant, wherein the aqueous phase is prepared without ingredients or additives which may react with, or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste, and thereby, at least retard the development of a metallic type off-flavour or fishy taste.

The invention also provides a spread prepared from the edible water-in-oil emulsion, as well as a spread prepared using the method of the invention.

The invention will be more clearly understood from the following description of the following non-limiting examples.

Example 1

A spread is prepared from an edible water-in-oil emulsion, which is prepared from the following ingredients in the proportions by weight of the water-in-oil emulsion set out below: Fat phase refined deodorised rape seed oil 22.6% Hydrogenated soya bean oil 12.9%

Dimodan 0T (glycerol mono stearate) 0.5% B Carotene 0.003%

Unhydrogenated fish oil containing an antioxidant blend 4.0%

Aqueous phase

De-ionised water 58.66% Sobalg FD 120 (sodium alginate) 1.20%

Potassium sorbate 0.10%

Citric acid 0.04%

The antioxidant blend of the unhydrogenated fish oil contains ascorbyl palmitate. In this particular embodiment of the invention the unhydrogenated fish oil is an unhydrogenated fish oil sold by Roche Products Limited of Great Britain under the Trade Mark ROPUFA "30" n-3 EPA Oil. The refined deodorised rape seed oil is liquid at room temperature, and the hydrogenated soya bean oil is firm at room temperature. The de-ionised water has a very low calcium content so that the calcium content of the aqueous phase is less than five parts per million of the aqueous phase.

The spread is prepared using a margarine process. The ingredients of the fat phase including the unhydrogenated fish oil are raised to a temperature of approximately 40°C to 45°C in a mixing tank until all the fats have melted and are thoroughly mixed. The ingredients of the aqueous phase are mixed and heated and the temperature of the aqueous phase is adjusted to lie in the range of 40°C to 45°C. The aqueous phase is then dispersed in the fat phase in the mixing tank and continuously stirred to form a water-in-oil emulsion. The emulsion is processed in a scraped surface heat exchanger and ancillary equipment to achieve pasteurisation, and is subsequently cooled and then subjected to texturising and/or plasticising. The spread is then packed as desired in foil, tubs or other suitable packaging.

Example 2

A spread is prepared from the following ingredients in the proportions by weight of the water-in-oil emulsion set out below using a similar method to that of Example 1:

Fat phase refined deodorised rape seed oil 22.6%

Hydrogenated soya bean oil 12.9%

Dimodan OT (glycerol mono stearate) 0.5% β Carotene 0.003% Unhydrogenated fish oil containing an antioxidant blend 4.0%

Aqueous phase

De-ionised water 57.16% Sobalg FD 120 (sodium alginate) 1.2%

Potassium sorbate 0.1%

Sodium chloride 1.5%

Citric acid 0.04%

Example 3

Fat phase refined deodorised rape seed oil 33.69%

Hydrogenated soya bean oil 19.8%

Dimodan 0T (glycerol mono stearate) 0.5% β Carotene 0.003%

Oil soluble flavour 0.01% Unhydrogenated fish oil containing an antioxidant blend 6.0%

Aqueous phase

De-ionised water 37.75%

Water soluble flavour 0.005% Sodium chloride 1.2%

Citric acid 0.04%

Example 4

Fat phase refined deodorised rape seed oil 15.5 % butterfat (anhydrous) 40.0% Dimodan OT (glycerol mono stearate) 0.5 - Unhydrogenated fish oil containing an antioxidant blend 4.0-

Aqueous phase De-ionised water 38.46%

Sodium chloride 1.5%

Citric acid 0.04%

Example 5

Fat phase refined deodorised rape seed oil 3.6%

Hydrogenated soya bean oil 26.0% Dimodan 0T (glycerol mono stearate) 0.4% β Carotene 0.003% Unhydrogenated fish oil containing an antioxidant blend 50.0% Aqueous phase

De-ionised water 19.96%

Citric acid 0.04%

Example 6 A water-in-oil emulsion, which is suitable for use as a bread shortening product is prepared from the following ingredients in the proportions by weight of the water-in-oil emulsion set out below using a similar method to that of Example 1:

Fat phase refined deodorised soya bean oil 21.4% Hydrogenated soya bean oil 45.8%

Dimodan OT (glycerol mono stearate) 1.2% Artodan CP80 (calcium stearoyl-2- lactylate) 1.6% Unhydrogenated fish oil containing an antioxidant blend 25.0%

Aqueous phase

De-ionised water 4.98%

Citric acid 0.02%

In Examples 2 to 6, the unhydrogenated fish oil is identical to the unhydrogenated fish oil used in Example 1. The emulsions of Examples 2 to 6 are prepared using a margarine process similar to the process described with reference to Example 1, and after texturising and plasticising the spreads of Examples 2 to 5 are packed. The bread shortening product of Example 6 is processed in a similar manner to the spreads of Examples 1 to 5 prior to packing, and is pasteurised, cooled, texturised and plasticised prior to packing. In each of Examples 2 to 5, the refined deodorised rape seed oil is liquid at room temperature. In Example 6 the refined deodorised soya bean oil is liquid at room temperature. In all the examples the de-ionised water has a very low calcium content, and in turn, the calcium content of the aqueous phase is less than five parts per million of the aqueous phase. In Examples 2, 3, 5 and 6 the hydrogenated soya bean oil is firm at room temperature. In Example 4 the butterfat is firm at room temperature. In each of the Examples 2 to 4, a small quantity of sodium chloride is included in the aqueous phase without adverse results.

In all the examples, as can be seen, neither the aqueous phase or the fat phase contain any of the following ingredients or additives: whey, whey powder, skimmed milk, skimmed milk powder, butter milk, butter milk powder, whole milk, whole milk powder, and sodium caseinate.

In all the examples, trace metals in the aqueous phase are kept to a minimum. The citric acid in the aqueous phase acts as a sequestrant, for binding the metal ions together in the aqueous phase.

All the spreads prepared according to Examples 1 to 5 and the bread shortening product of Example 6 were found to have a relatively long shelf life, the shortest of which was in the case of the spread of Example 5 which had a shelf life of 12 weeks before the development of a metallic type off-flavour or fishy taste could be detected, and the longest of which was the spread of Example 1 which had a shelf life of 20 weeks before a metallic type off-flavour or fishy taste could be detected. The bread shortening product of Example 6 was found to have a shelf life of 16 weeks.

Spreads substantially similar to those of Examples 1 to 5 and a bread shortening product substantially similar to that of Example 6 have been prepared, however, these spreads have been prepared with an aqueous phase which included either whey, whey powder, butter milk or whole milk. In some cases, the water was not de- ionised, and none of these spreads included a metal sequestrant in the aqueous phase. All these spreads and the bread shortening product within a reasonably short time, typically, 1 week developed a metallic type off-flavour or a fishy taste. A 17 specific example of a spread which was prepared with an aqueous phase which included a milk protein containing ingredient, namely, whey powder is described below in Example 7.

Example 7 The spread was prepared from a water-in-oil emulsion which was prepared from the following ingredients in the proportions by weight of the water-in-oil emulsion set out below:

Fat phase

Refined deodorised rape seed oil 22.6% Hydrogenated soya bean oil 12.8%

Unhydrogenated fish oil 4.0%

Dimodan OT 0.6% β Carotene (30% suspension) 0.0035%

Aqueous phase Distilled water 56.93%

Sobalg FD 120 1.20%

Whey powder 0.5%

Lactic acid 0.03%

Salt 1.2% Potassium sorbate 0.1%

The unhydrogenated fish oil was identical to the unhydrogenated fish oil of Example 1. The water of the aqueous phase was not de-ionised and did not contain a metal sequestrant. The water being distilled would have had a relatively low calcium content.

The water-in-oil emulsion was prepared using a margarine process identical to that used in the preparation of the spreads of Examples 1 to 5, and the spread was texturised and plasticised and packed in similar fashion as the spreads of Examples 1 to 5. It was found that the spread of this Example 7 developed a metallic type fishy off-flavour within two days.

It is therefore believed that by preparing the emulsions which comprise unhydrogenated fish oil containing an antioxidant without ingredients or additives which would react with or would act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause development of metallic type off- flavour or fishy taste an emulsion is provided in which, in general, the development of the metallic type off-flavour or fishy taste is prevented or at least retarded, thereby, providing a product with a relatively long shelf life, which has been found, in general, typically to be 16 weeks.

It is believed that the avoidance of whey and other milk protein containing ingredients and additives as well as sodium caseinate in the aqueous phase contributes to the results achieved according to the invention. It is also believed that the use of de-ionised water further contributes to the results of the invention. The provision of a sequestrant in the aqueous phase binds the metal ions, thereby further contributing to the results of the invention, and by providing an aqueous phase with a low calcium content any adverse effect on the effectiveness of the sequestrant which may be caused by calcium is minimised or eliminated.

While the water-in-oil emulsion has been described in the examples as being a spread or a bread shortening product, it will be apparent to those skilled in the art that the edible water-in- oil emulsion may be other than a spread or a bread shortening.

The invention is not limited to the examples hereinbefore described, and it will be readily apparent to those skilled in the art that other edible water-in-oil emulsions containing unhydrogenated fish oil may be prepared according to the invention with other ingredients and other proportions of ingredients.

Claims

1. A method for preparing an edible water-in-oil emulsion containing unhydrogenated fish oil, the water-in-oil emulsion comprising a fat phase and an aqueous phase, the fat phase comprising unhydrogenated fish oil containing an antioxidant, characterised in that the aqueous phase is prepared without ingredients or additives which may react with, or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste, and thereby, at least retard the development of a metallic type off-flavour or fishy taste.

2. A method as claimed in Claim 1 characterised in that the antioxidant contained in the unhydrogenated fish oil is an antioxidant blend.

3. A method as claimed in Claim 1 or 2 characterised in that the antioxidant contained in the unhydrogenated fish oil comprises ascorbyl palmitate.

4. A method as claimed in any preceding claim characterised in that the aqueous phase is prepared without ingredients or additives which may react with or may act as a catalyst for a reaction with the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste.

5. A method as claimed in any preceding claim characterised in that the aqueous phase is prepared without ingredients or additives which may react with or may act as a catalyst for a reaction with a constituent ingredient of the antioxidant to cause the water-in-oil emulsion to develop a metallic type off- flavour or fishy taste.

6. A method as claimed in any preceding claim characterised in that milk protein containing ingredients in any significant amounts are excluded from the aqueous phase.

7. A method as claimed in Claim 6 characterised in that milk protein containing ingredients are excluded from the aqueous phase.

8. A method as claimed in any preceding claim characterised in that the aqueous phase is prepared without any one or more of the following ingredients or additives being present therein in any significant amounts: whey, whey powder, skimmed milk, skimmed milk powder, butter milk, butter milk powder, whole milk, whole milk powder, and sodium caseinate.

9. A method as claimed in Claim 8 characterised in that the following ingredients are excluded from the aqueous phase: whey, whey powder, skimmed milk, skimmed milk powder, butter milk, butter milk powder, whole milk, whole milk powder, and sodium caseinate.

10. A method as claimed in any preceding claim characterised in that the aqueous phase is prepared with de-ionised water.

11. A method as claimed in any preceding claim characterised in that a sequestrant is added to the aqueous phase for binding metal ions in the aqueous phase.

12. A method as claimed in Claim 11 characterised in that the sequestrant is selected from any one or more of the following sequestrants: citric acid and/or its salts, phosphate salts, and ethylene diamine tetra-acetic acid and/or its salts.

13. A method as claimed in any preceding claim characterised in that the aqueous phase is prepared with water having a relatively low calcium content.

14. A method as claimed in Claim 13 characterised in that the calcium content of the water of the aqueous phase is very low.

15. A method as claimed in Claim 13 or 14 characterised in that the calcium content of the aqueous phase is less than 20 parts per million of the aqueous phase.

16. A method as claimed in Claim 15 characterised in that the calcium content of the aqueous phase is less than 10 parts per million of the aqueous phase.

17. A method as claimed in Claim 16 characterised in that the calcium content of the aqueous phase is less than 5 parts per million of the aqueous phase.

18. A method as claimed in any preceding claim characterised in that the fat phase constitutes up to 95% by weight of the water- in-oil emulsion.

19. A method as claimed in Claim 18 characterised in that the fat phase constitutes up to 82% by weight of the water-in-oil emu1sion.

20. A method as claimed in Claim 19 characterised in that the fat phase constitutes up to 60% by weight of the water-in-oil emulsion.

21. A method as claimed in Claim 20 characterised in that the fat phase constitutes approximately 40% by weight of the water- in-oil emulsion.

22. A method as claimed in any preceding claim characterised in that the unhydrogenated fish oil containing the antioxidant constitutes up to 50% by weight of the water-in-oil emulsion.

23. A method as claimed in Claim 22 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes up to 40% by weight of the water-in-oil emulsion.

24. A method as claimed in Claim 23 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes up to 30% by weight of the water-in-oil emulsion.

25. A method as claimed in Claim 24 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes between 3% and 20% by weight of the water-in-oil emulsion.

26. A method as claimed in Claim 25 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes approximately 4% by weight of the water-in-oil emulsion.

25 27. A method as claimed in any preceding claim characterised in that the unhydrogenated fish oil is an unhydrogenated fish oil sold by Roche Products Limited of Great Britain under the Trade Mark ROPUFA "30" n-3 EPA Oil.

28. A method as claimed in any preceding claim characterised in that the fat phase comprises at least one vegetable oil.

29. A method as claimed in Claim 28 characterised in that at least one of the vegetable oils is liquid at room temperature.

30. A method as claimed in Claim 28 or 29 characterised in that the vegetable oil is selected from any one or more of the following oils: rape seed oil , soya bean oil , sun flower oil , and olive oil .

31. A method as claimed in any preceding claim characterised in that the fat phase comprises a hard stock fat firm at room temperature.

32. A method as claimed in Claim 31 characterised in that the hard stock fat is a vegetable oil.

33. A method as claimed in Claim 31 or 32 characterised in that the hard stock fat is selected from any one or more of the following oils: hydrogenated or partly hydrogenated soya bean oil, hydrogenated or partly hydrogenated rape seed oil, hydrogenated or partly hydrogenated palm oil, hydrogenated or partly hydrogenated coconut oil, hydrogenated or partly hydrogenated palm kernel oil, a vegetable oil naturally hard at room temperature, for example, coconut oil, palm kernel oil, palm oil and fractions thereof, and animal fats, for example, milk fat, tallow, lard and fractions thereof.

34. A method as claimed in any preceding claim characterised in that the fat phase contains an emulsifier.

35. A method as claimed in Claim 34 characterised in that the emulsifier is a mono and/or diglyceride of fatty acids.

36. A method as claimed in any preceding claim characterised in that the water-in-oil emulsion contains a colouring, a flavouring and/or vitamins.

37. A method as claimed in any preceding claim characterised in that the aqueous phase contains lactic acid, proteins and/or flavouring additives.

38. A method as claimed in any preceding claim characterised in that the water-in-oil emulsion is prepared using a margarine process.

39. An edible water-in-oil emulsion containing unhydrogenated fish oil, the water-in-oil emulsion comprising a fat phase and an aqueous phase, the fat phase comprising unhydrogenated fish oil containing an antioxidant, characterised in that the aqueous phase is prepared without ingredients or additives which may react with, or may act as a catalyst for a reaction with the unhydrogenated fish oil and/or the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste, and thereby, at least retard the development of a metallic type off-flavour or fishy taste.

40. An edible water-in-oil emulsion as claimed in Claim 39 characterised in that the antioxidant contained in the unhydrogenated fish oil is an antioxidant blend.

41. An edible water-in-oil emulsion as claimed in Claim 39 or 40 characterised in that the antioxidant contained in the unhydrogenated fish oil comprises ascorbyl palmitate.

42. An edible water-in-oil emulsion as claimed in any of Claims 37 to 39 characterised in that the aqueous phase is prepared without ingredients or additives which may react with or may act as a catalyst for a reaction with the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste.

43. An edible water-in-oil emulsion as claimed in any of Claims 37 to 40 characterised in that the aqueous phase is prepared without ingredients or additives which may react with or may act as a catalyst for a reaction with a constituent ingredient of the antioxidant to cause the water-in-oil emulsion to develop a metallic type off-flavour or fishy taste.

44. An edible water-in-oil emulsion as claimed in any of Claims 39 to 43 characterised in that the aqueous phase does not contain any significant amounts of milk protein containing ingredients.

45. An edible water-in-oil emulsion as claimed in Claim 44 characterised in that the aqueous phase does not contain any milk protein containing ingredients.

46. An edible water-in-oil emulsion as claimed in any of Claims 39 to 45 characterised in that the aqueous phase is prepared without any one or more of the following ingredients or additives being present therein in any significant amounts: whey, whey powder, skimmed milk, skimmed mil powder, butter milk, butter milk powder, whole milk, whole milk powder, and sodium caseinate.

47. An edible water-in-oil emulsion as claimed in Claim 46 characterised in that the following ingredients and/or additives are excluded from the aqueous phase: whey, whey powder, skimmed milk, skimmed milk powder, butter milk, butter milk powder, whole milk, whole milk powder, and sodium caseinate.

48. An edible water-in-oil emulsion as claimed in any of Claims 39 to 47 characterised in that the aqueous phase is prepared with de-ionised water.

49. An edible water-in-oil emulsion as claimed in any of Claims 39 to 48 characterised in the aqueous phase contains a sequestrant for binding metal ions in the aqueous phase.

50. An edible water-in-oil emulsion as claimed in Claim 49 characterised in that the sequestrant is selected from any one or more of the following sequestrants: citric acid and/or its salts, phosphate salts, and ethylene diamine tetra-acetic acid and/or its salts.

51. An edible water-in-oil emulsion as claimed in any of Claims 39 to 50 characterised in that the aqueous phase is prepared with water having a relatively low calcium content.

52. An edible water-in-oil emulsion as claimed in Claim 51 characterised in that the calcium content of the water of the aqueous phase is very low.

53. An edible water-in-oil emulsion as claimed in Claim 51 or 52 characterised in that the calcium content of the aqueous phase is less than 20 parts per million of the aqueous phase.

54. An edible water-in-oil emulsion as claimed in Claim 53 characterised in that the calcium content of the aqueous phase is less than 10 parts per million of the aqueous phase.

55. An edible water-in-oil emulsion as claimed in Claim 54 characterised in that the calcium content of the aqueous phase is less than 5 parts per million of the aqueous phase.

56. An edible water-in-oil emulsion as claimed in any of Claims 39 to 55 characterised in that the fat phase constitutes up to 95% by weight of the water-in-oil emulsion.

57. An edible water-in-oil emulsion as claimed in Claim 56 characterised in that the fat phase constitutes up to 82% by weight of the water-in-oil emulsion.

58. An edible water-in-oil emulsion as claimed in Claim 57 characterised in that the fat phase constitutes up to 60% by weight of the water-in-oil emulsion.

59. An edible water-in-oil emulsion as claimed in Claim 58 characterised in that the fat phase constitutes approximately 40% by weight of the water-in-oil emulsion.

60. An edible water-in-oil emulsion as claimed in any of Claims 39 to 59 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes up to 50% by weight of the water-in-oil emulsion.

61. An edible water-in-oil emulsion as claimed in Claim 60 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes up to 40% by weight of the water-in-oil emulsion.

62. An edible water-in-oil emulsion as claimed in Claim 61 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes up to 30% by weight of the water-in-oil emulsion.

63. An edible water-in-oil emulsion as claimed in Claim 62 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes between 3% and 20% by weight of the water-in-oil emulsion.

64. An edible water-in-oil emulsion as claimed in Claim 63 characterised in that the unhydrogenated fish oil containing the antioxidant constitutes approximately 4% by weight of the water- in-oil emulsion.

65. An edible water-in-oil emulsion as claimed in any of Claims 39 to 64 characterised in that the unhydrogenated fish oil is an unhydrogenated fish oil sold by Roche Products Limited of Great Britain under the Trade Mark ROPUFA "30" n-3 EPA Oil.

66. An edible water-in-oil emulsion as claimed in any of Claims 39 to 65 characterised in that the fat phase comprises at least one vegetable oil .

67. An edible water-in-oil emulsion as claimed in Claim 66 characterised in that at least one of the vegetable oils is liquid at room temperature.

68. An edible water-in-oil emulsion as claimed in Claim 66 or 67 characterised in that the vegetable oil is selected from any one or more of the following oils: rape seed oil, soya bean oil , sun flower oil , and olive oil .

69. An edible water-in-oil emulsion as claimed in any of Claims 39 to 68 characterised in that the fat phase comprises a hard stock fat firm at room temperature.

70. An edible water-in-oil emulsion as claimed in Claim 69 characterised in that the hard stock fat is a vegetable oil.

71. An edible water-in-oil emulsion as claimed in Claim 69 or 70 characterised in that the hard stock fat is selected from any one or more of the following oils: hydrogenated or partly hydrogenated soya bean oil, hydrogenated or partly hydrogenated rape seed oil, hydrogenated or partly hydrogenated palm oil, hydrogenated or partly hydrogenated coconut oil, hydrogenated or partly hydrogenated palm kernel oil, a vegetable oil naturally hard at room temperature, for example, coconut oil, palm kernel oil, palm oil and fractions thereof, and animal fats, for example, milk fat, tallow, lard and fractions thereof.

72. An edible water-in-oil emulsion as claimed in any of Claims 39 to 71 characterised in that the fat phase contains an emulsifier.

73. An edible water-in-oil emulsion as claimed in Claim 72 characterised in that the emulsifier is a mono and/or diglyceride of fatty acids.

74. An edible water-in-oil emulsion as claimed in any of Claims 39 to 73 characterised in that the water-in-oil emulsion contains a colouring, a flavouring and/or vitamins.

75. An edible water-in-oil emulsion as claimed in any of Claims 39 to 74 characterised in that the aqueous phase contains lactic acid, proteins and/or flavouring additives.

76. An edible water-in-oil emulsion as claimed in any of Claims 39 to 75 characterised in that the water-in-oil emulsion is prepared using a margarine process.

77. A spread prepared from the edible water-in-oil emulsion as claimed in any of Claims 39 to 76.

78. A spread as claimed in Claim 77 characterised in that the water-in-oil emulsion is prepared according to the method as claimed in any of Claims 1 to 38.