GB2292949A - Stick-type margarines and spreads containing no trans fatty acid - Google Patents

Abstract

The present invention relates to stick-type margarines and other spreads which contain no detectable levels of trans fatty acids or tropical oils (e.g. coconut or palm) and which possess the desired margarine or spread characteristics of butter-like appearance, flavor, and physical properties equivalent to stick-type margarine which do contain trans fatty acids or tropical oils. The emulsified products of the present invention comprise specific blends of co-interesterified liquid unsaturated vegetable oils hardstocks, with the incorporation of a fully hydrogenated mono-glyceride emulsifier.

Description

FAT SYSTEMS AND PROCESSES FOR THE PRODUCTION OF NO TRANS FATTY ACID CONTAINING STICK-TYPE MARGARINES AND SPREADS BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to unique stick-type margarines and spreads which do not contain trans fatty acids but which possess the desired margarine characteristics of butter-like flavor, color and physical properties equivalent to stick-type margarines which do contain trans fatty acids. More particularly, the unique fat or oil system(s) of the present invention, which also do not include any tropical oils, are chemically interesterified to achieve both physical and functional characteristics comparable to hydrogenated oils.

Additionally, the final margarine blends require specific emulsifiers and preferably are manufactured according to specific processing parameters in order to achieve the desired stick-type margarine or spread products.

DESCRIPTION OF THE PRIOR ART Margarine is a fatty food manufactured in semblance of butter in flavor, color, physical properties and composition except that the fat is not principally milkfat. More specifically, margarine is generally a water-in-oil emulsion, i.e. a suspension of one liquid within a second immiscible liquid. In margarine the fat component is known as the continuous or oil phase while the dispersed or aqueous phase consists of water and/or water dispersible components. Margarine is generally defined as a composition containing at least 80% fat (or oil) by weight and about 20% by weight aqueous phase. In contrast, emulsions containing less than 80% by weight fat are spreads. Both are manufactured in several forms including stick, tub, whipped and liquid forms.

The fat in margarine is primarily completely processed (i.e. refined, bleached, hydrogenated and deodorized) mixed triglycerides (also known as triacylglycerols) of vegetable or animal carcass origin.

Triglycerides are triesters of glycerol and various saturated and unsaturated fatty acids. The physical properties of fats are determined by the characteristics of the individual fatty acid moieties and by their distribution within the triglyceride molecule. For purposes of making a suitable stick-type margarine, the fat must have a plastic consistency at refrigeration or ambient temperatures and yet have the essential characteristic of melting readily and with substantial completeness in the mouth of the consumer. Such a melting characteristic normally requires a solid fat index (SFI), which has specific values over a temperature range established by accepted methodology [American Oil Chemists' Society (AOCS) Official Method Cd 10-57].In addition, plastic margarine fats must have a crystal habit which provides a smooth organoleptic consistency without graininess or similar mouthfeel defects in homogeneity.

The physical properties of the margarine are derived predominantly from the composition of the fat, as well as the processing technique in making the margarine.

Margarine is generally prepared from edible fats which are physically modified by hydrogenation and/or interesterification. In the United States, hydrogenation has been the principal means of oil modification.

Hydrogenation is the chemical reaction of fats and oils with hydrogen gas in the presence of a catalyst which results in the addition of hydrogen to the fat, thus transforming unsaturated bonds into saturated bonds along with other reactions. The process of hydrogenation of fats results in the raising of the melting point of edible fats and improving the resistance of the fat to oxidative deterioration. Hydrogenation also generates positional and geometrical isomers.

Tropical oils, such as coconut, palm and palm kernal have been conventionally utilized as a component of margarine fats as they have acceptable melting and solidification properties resulting from their higher levels of intermediate carbon chain saturated fatty acids. However, consumers have been increasingly concerned in recent years about the saturated fat content in the foods they eat and the effect of such foods on their health. In fact, saturated fat has been shown in numerous studies to increase levels of cholesterol in the blood and has been linked to increased risk of heart disease. Consequently, it is no surprise that consumers conscientiously look for foods low in saturated fat content.Accordingly, in order to reduce the saturated fat, it is desirable to find suitable replacements for tropical oils in margarine formulas with alternatives that maintain the same flavor, color and physical properties provided by tropical oils.

Vegetable oils or domestic oils, i.e. non-tropical oils, such as soybean, corn, cottonseed, peanut, sesame, and the like, may be partially hydrogenated in order to achieve margarine oils of the requisite physical characteristics which tropical oils provide. Usually, selectively hydrogenated oils are blended in order to achieve the required physical characteristics for margarine. More particularly, the desired consistency has been typically obtained by blending two or more partially hydrogenated vegetable oils, or blending liquid (unhydrogenated) vegetable oil with a partially hydrogenated vegetable oil.Conventional partial hydrogenation of vegetable oils containing unsaturated acids, depending on catalyst selectivity, degree of hydrogenation and other processing variables, produce substantial amounts of unsaturated fatty acids of the trans-configuration rather than the naturally occurring cis-configuration.

The term "trans-acid" or "trans fatty acid" as used herein refers to an unsaturated fatty acid having a -carbon chain length of from generally 16 to 24 carbon atoms and having at least one unsaturated carbon-carbon bond which is in the trans-configuration. In conventional margarine fat prepared from partially hydrogenated vegetable oil, the trans acid content may exceed 25% by weight or more of the margarine fat composition. This is a result of the partial hydrogenation conditions which are required to provide an acceptable solid fat index for a margarine fat. Unfortunately, the presence of such trans isomers of fatty acids in the diet have also become the target of concern in relation to the consumers' dietary health.Accordingly, margarine fat systems are desired which contain no detectable amounts of such trans acid moieties, or are present at levels which are nutritionally insignificant, yet have the flavor, color and physical properties of margarines which contain tran fatty acids.

Apart from vegetable oils being hydrogenated to achieve desired results, vegetable oils intended to be used for any food preparation purposes are also processed by first subjecting them to the well known techniques of alkali or physical refining, bleaching and steam deodorization. See Bailey's Industrial Oil And Fat Products, Wiley-Interscience Publishers (1982), Chapter 4 of Volume 2 for a detailed description of refining and bleaching, and Chapter 3 of Volume 3'for a detailed description of deodorization, both of which are incorporated by reference herein.

The alternate method of chemically modifying edible fats mentioned earlier is the process of interesterification and the related process of transesterification. This is a technique which may also be used to alter the triglycerides profile and therefore ultimately the physical properties of the resulting triglyceride mixtures. Both chemical and enzymatic interesterification are well known for modifying the triglyceride profile of fats and oils.

Chemical interesterification is based on the use of a chemical catalyst, such as sodium methoxide or sodium metal, to promote the migration of the fatty acid moieties between triglyceride molecules and to produce a random redistribution of the fatty acid moieties.

Enzymatic transesterification may be used for selective interchange under relatively mild reaction conditions.

As stated earlier, in addition to the composition of the fat, the physical properties of the margarine are also influenced by the processing parameters. In standard margarine manufacture, the aqueous phase is dispersed in the oil phase and the resulting emulsion is then sent through a scraped surface heat exchanger such as a Votator A-Unit. The A-Unit supercools the emulsion with relatively short residence time. The supercooled emulsion" is then sent to a crystallizer known as a static B-Unit, in the form of a jacketed hollow tube or "resting tube", normally used to provide firm stick-type margarine. By comparison, "working B-Units", for example in the form of picker units, serve to break up larger crystals, which affects solidification properties.

SUMMARY OF THE INVENTION The present invention relates to stick-type margarines and spreads which are essentially free of trans fatty acids or tropical oils but yet possess the butter-like attributes of margarines which contain and are dependent upon the existence of trans fatty acids or tropical oils. More specifically, the butter-like characteristics of the stick-type margarines and spreads made in accordance with the present invention are obtained by the use of specific oil blends which are to be used as the base oil in the emulsion, the use of specific emulsifiers and the preferred implementation of specific processing parameters. By essentially free of trans fatty acids is meant that the level of trans fatty acids is negligible, typically below 2% by weight of the margarine oil.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram illustrating the process of making stick-type margarines and spreads in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to stick-type margarines and spreads which not only possess all of the desired butter-like characteristics such as flavor, color and physical properties, but which also meet growing health concerns. That is, the stick-type margarines and spreads made in accordance with the present invention are essentially free of trans fatty acids, the isomeric form of unsaturated fatty acids which have been linked to health risks such as heart disease. In addition, the stick-type margarines and spreads of the present invention do not incorporate tropical oils which contain relatively high levels of saturated fatty acids. Certain saturated fatty acids have been identified as having potential health risks.

It has surprisingly been found that stick-type margarines and spreads can be made essentially free of trans fatty acids or tropical oils and yet maintain the desired qualities of a superior margarine or spread product. The stick-type products made in accordance with the present invention can be obtained by the implementation of a combination of factors, namely a unique oil blend to be used as the base oil in formulating the margarine or spread emulsion, specific emulsifiers and preferably specific processing conditions which deviate from the conventional processes involved in making margarines and spreads but which enable comparable products of the present invention to be made.

As stated above, the oil blends to be used in formulating the base oil fat blend of the margarine or spread emulsion is the first important factor critical to the present invention. The base oil of the present invention is comprised of only domestic oils, i.e. no tropical oils are present.

More particularly, the base oil, which is utilized in the present invention, is a blend of refined domestic vegetable oil (i.e. liquid oil) and refined and bleached fully hydrogenated vegetable oil (hereinafter referred to as "hardstock"). This specific blend is subjected to the interesterification reaction which may be random, directed or enzymatic. In the case of random interesterification, the reaction is generally carried out with about 0.1% to about 0.5% by wt. (usually based on starting free fatty acids (FFA)) of a suitable catalyst, for example, preferably sodium methoxide (methylate) at temperatures from about 60"C to about 1000C for a period of about 3 to about 120 minutes with agitation while under vacuum or inert atmosphere.After the reaction achieves equilibrium, the reaction is terminated through catalyst inactivation with either 1% to 3% by wt. of water or a dilute acid solution such as citric or phosphoric acid. The subsequent removal of residues, such as metallic soaps and mono-diglycerides, is carried out by traditional edible oil processing methods which include, but is not limited to, water washing, centrifugation, vacuum drying, bleaching with acid activated or neutral bleaching/filtering media and deodorization.

The base oil to be used in the present invention is an co-interesterified blend of a domestic oil, preferably a refined and bleached domestic oil and a refined, bleached and deodorized hardstock in proportions by weight of about 85:15 to about 60:40, preferably from about 80:20 to about 70:30. It is again noted that it is important that the vegetable oil hardstock be fully hydrogenated, and thus fully saturated in order that no trans fatty acids are formed. It is further noted that the hardstock have an Iodine Value (IV) of less than or equal to 5.

The IV of a fat or oil measures the number of grams of Iodine absorbed by 100 grams of sample as determined by A.O.C.S. Method Cd 1-25, also known as the wijs method. Iodine is absorbed by double bonds within the fatty acids comprising an oil or fat molecule (triglyceride) which is given to be an indication of an oil or fat's relative unsaturation. The amount of solid fat present at a given temperature for unhydrogenated fats or oils relates to the amount of saturated fatty acids found in the array or triglycerides unique to the fat or oil. Therefore, the lower the IV of a given fat or oil, the greater the saturation and solid content will be at a given temperature. For example, cocoa butter and cocoa butter substitutes and extenders usually have an IV of about 35 or less.

Although refined and bleached, soybean oil and canola oil are preferred as the domestic vegetable oil to be used in the base oil of the present invention, other domestic vegetable oils can be used. They include, but are not limited to, cottonseed oil, corn oil, peanut oil, sunflower oil, safflower oil, high erucic acid rapeseed oil (HEAR) and the like, as well as genetically altered varieties of these oils.

Similarly, the hardstock to be used in the oil blend of the present invention, together with the domestic vegetable oil, may be chosen from a wide variety of edible liquid vegetable oils or domestic oils, including soybean oil, cottonseed oil, corn oil, canola, peanut oil, sunflower oil, safflower oil, high erucic acid rapeseed oil (HEAR) and the like. Cottonseed oil, soybean oil and mixtures thereof are most preferred as the hardstock, as well as genetically altered varieties of these oils.

The base oil compositions described above are to be used in making stick-type margarine or spreads. In the market place, margarine is generally sold as one of two principal types, print or stick, and soft or tub margarine with minor amounts sold as whipped or liquid.

Print or stick-type margarine generally have a firmness consistent with a penetration range of from 35 to 120, said measurement being in units of 0.1 mm using an ASTM (7.200).

grease cone at 45OF/ Soft or tub margarine, on the other hand, as one would expect, does not have to be as hard as stick-type margarine and generally has a firmness consistent with a penetration range of from 130 to 250.

Lesser amounts of margarine are sold in a form so soft that it is fluid, being at least capable of being squeezed from a flexible container. Accordingly, it can be seen that depending upon the desired product type, both composition of the oil phase, as well as the processing parameters, play an important role.

The stick-type margarine base oil formulas in accordance with the present invention further include emulsifiers which will be discussed below. It is noted here, however, that without the addition of the specific base oil and specific emulsifiers, the emulsion products would not have the necessary plasticity, i.e.

spreadability, mouthfeel, or the thermal stability (cycling from refrigerated to room temperatures) necessary for acceptable stick-type products.

The mixtures of oils or fats to be used in the stick base oil formulas of the present invention are interesterified, in admixture or separately, and surprisingly achieve physical and functional characteristics comparable to hydrogenated oils, without the presence of trans fatty acids which are normally found in partially hydrogenated oils.

For the purpose of making margarines, the oil phase described above must make up at least 80% by weight of the margarine to meet the fat requirement set forth by the Standards of Identity for margarine. Still, the present invention is further directed to the use of the oil blends described above in the preparation of calori reduced margarines (diet margarines), bulk food processor margarine and spreads, blends with dairy products and other spreads containing less than 80% by weight fat by weight. For purposes of making emulsified products, which include margarine and spreads, the oil phase may range from about 25% to 90% by weight.

It is important to note that the percentages of said oil phases given above include, in addition to the indicated base oil, emulsifiers, and optional colorings, oil-soluble flavors, vitamins and antioxidants.

Of the additional components which may be added to the oil phase in addition to the base oil, the second critical factor for the purposes of making the products in accordance with the present invention is the presence of specific emulsifiers. The specific emulsifiers to be used in the oil phase of the present invention are nonplastic fully hydrogenated distilled monoglycerides such as Myverol 1807to' (Eastman Chemical, Kingsport, TN).

Lecithin is also used in the oil phase of the emulsions in accordance with the present invention. The nonplastic distilled monoglycerides act to help formulate the water-in-oil emulsion and, in addition, provides necessary physical integrity and plasticity to allow machinability (forces inherent in forming and packaging).

Lecithin, to a lesser extent, has the same function as conventional emulsifiers. However, lecithin also functions to impart the primary salt perception to the product as well as being a known anti-spattering additive. The non-plastic distilled monoglycerides may be present in the oil phases of the present invention in an amount from about 0.2t to about 3.08 by weight based upon the total weight of the margarine or spread.

Preferably, the non-plastic distilled monoglycerides are present in an amount of from about 0.3% to about 1.0% by weight.

With respect to the optional components of the oil phase, examples of typical coloring agents which may be added include beta-carotene, annatto, turmeric, paprika, FD & C dyes and the like. Various oil-soluble flavors which may be added to the oil phase of the fat blends of the present invention include lipolyzed butter oils, diacetyl, 2-octanone, butyric acid, hexanoic acid and the like. Examples of vitamins which may be added to the oil phase include Vitamin A and its derivatives. In addition, antioxidants, such as TBHQ (or other approved phenolic-type antioxidants), can also be added into the oil phase mix.

In addition to the oil phase, the emulsions used to make the products of the present invention must also contain an aqueous phase which ranges from 10% to 75t by weight of the emulsion. The aqueous or water phase of the emulsions in accordance with the present invention is comprised of conventionally known components and may include water-soluble flavors, milk or milk solids, whey solids, salt, preservatives, casein, caseinates, albumin, water and other suitable margarine ingredients. The milk component can be derived from whole milk, low-fat milk ( < 2% butter fat content), skim milk or nonfat dry milk solids. The amount of milk and/or milk solids (in terms of % by weight solids) usually ranges from about 0.5% to about 5% by weight of the emulsified product and more typically from about 1% to about 3% by weight.

Particularly where milk solids are incorporated as a protein source, potable water is included as part of the aqueous phase. Salt may also be included in an amount of from about 0.5% to about 3 5t by weight of the emulsified spread and more typically in an amount of from about 1% to about 2.5t by weight. The amount of other water soluble flavors depends upon the particular flavor characteristics desired. Examples of preservatives which are added in amounts to prevent or retard bacterial and mold growth, include citric acid, potassium sorbate, EDTA, sodium benzoate, sorbic acid and the like.

The aqueous phase, thus comprising preferably potable water, a suitable protein source, salt, and appropriate preservatives, is slowly added and blended with the oil phase at a temperature from about 4CC to about 630C to form an emulsion. The ingredients may be formulated in separate mix tanks from which they are metered out into another tank where the aqueous phase is dispersed in the melted oil phase. The emulsion is then processed under processing conditions to produce the final product.

Figure 1 is a schematic diagram of the processing steps and conditions which result in the stick-type margarine and spreads of the present invention. With reference to Figure 1, the emulsion (2), i.e. the combined oil and aqueous phases, is fed from a storage tank (4) via a supply pump (6) and a positive displacement pump (8) to a scraped surface heat exchanger (10). An example of a scraped surface heat exchanger is the Votator A-Unit. The A-Unit (10) usually consists of a stainless steel shaft (mutator shaft) rotating accentically inside a shell which is cooled externally by liquid ammonia or brine solution or other refrigerant.

The rotating mutator shaft is fitted with scraper blades which at high rotation speeds are pressed against the cooled inner surface. The rotation speed of the scraper blades by definition is proportional to the extent of supercooling the emulsion. The internal pressures and chilling action supercools the emulsion in the A-Unit (it).

It has surprisingly been found that given the specific oil base in accordance with the present invention, there exists a unique relationship between improved machinability of the products produced and the degree of supercooling in the A-Unit (10), as well as the incorporation of an extrusion valve (16) between the exit of the A-Unit and the entrance of the crystallization tube (18), which will provide the necessary shear to enhance solidification properties.

The invention will be described, in relation to experiments, and pilot plant runs conducted on a pilot scale Votator Model No. S3/41A manufactured by Cherry Burrell Process Equipment (Louisville, Kentucky) which was fitted with an extrusion valve Part No. 201848 also manufactured by Cherry-Burrell. The back pressures, extrusion pressures, rpms and pump pressures set forth, hereinafter, relate specifically the aforementioned equipment. One skilled in the art would be able to utilize this information, in arriving at suitable processing conditions for other equipment. However, it is preferred in all cases, with all equipment, to incorporate an extrusion valve located between the exit of the A-Unit and the entrance of the crystallization tube.The extrusion valve will produce a smaller crystal size, which will in turn enhance the formability of the margarine or spread product, thereby facilitating crystallization rate and making the product more machinable. The extrusion valve, in this application, produces a different function than the more commonly utilized back pressure valve. The extrusion valve produces high shear, in that it provides a constant flo and maintains a constant pressure and shearing/homogenization action as a consequence of its design. This is in direct contrast with a back pressure valve, which has a primary function of regulating and maintaining proper volume in the A-Unit to insure efficient, uniform chilling.

More specifically, in conventional processing, when utilizing the previously-identified equipment the mutator shaft speed of the A-Unit (10) is usually about 200+20 rpms while both the pump pressure (12) and back pressure (14) range from about 50 to about 75 psi (about 3.45 to about 5.17 bar). In accordance with the present invention, the mutator shaft speed of the A-Unit (10) can be set somewhat higher than that used in conventional processing. Optimum integrity of the final product is obtained when the A-Unit operates from about 200 to about 275 rpms. The pump pressure (12) is significantly higher in the process of the present invention at a pressure of from about 250 to about 350 psi (about 17.24 to about 24.13 bar), with a pressure of about 300 psi (about 20.68 bar) being preferred.The process of the present invention also employs an extrusion valve (16) positioned near the entrance to the crystallization tube (18) in order to maintain a system pressure (14) of from about 225 to about 425 psi (about 15.51 to about 29.30 bar), which is also significantly greater than conventional processing conditions. The preferred extrusion pressure to be maintained in the method of the present invention is between about 250 to about 350 psi (about 17.24 to about 24.13 bar).Pressures below 225 psi (15.51 bar) result in a product too soft to form while a pressure of 425 psi (29.30 bar) or greater results in a product exhibiting signs of emulsion stress (i.e. weeping) However, modern equipment for high speed processing allows pressures up to 1200 psi (82.74 bar) . It has been found that with the increased pump pressure and extrusion pressures employed by the process of the present invention, the formability of the product is improved greatly and a superior product is obtained.

The temperature within the A-Unit (10) ranges from about 40C to about 10 C. The emulsion is discharged from the A-Unit (10) and through the extrusion valve (16) at a temperature of from about 10"C to about 130C. The total residence time within the A-Unit (10) ranges from about 2.5 seconds to about 3.5 seconds.

The chilled emulsion from the A-Unit (10) is then supercooled without further working by being pumped to a static crystallization tube (18). Residence time in the resting tube is a function of the rate which best achieves the integrity necessary for filling or forming and wrapping.

The residence time of the emulsion in the crystallization tube (18) is at least about 1.6 minutes and is more typically from about 1.6 to about 5 minutes.

The temperature in the static crystallization tube (18) generally ranges from about lOCC to about 13 C.

The crystallized emulsion leaves the resting tube (18) and is fed into the former (20) where it is packed as the final stick-type margarine product. For the stick-type products of the present invention, the former (20) is a square die which either extrudes or molds the margarine product into sticks by techniques well known in the margarine art. The packed margarine is usually tempered at a temperature of from about -10C to about 10"C for at least a period of about 24 hours or until crystal stability is achieved.

Thus, it has been found by employing the specific blends of co-interesterified liquid oils and hardstocks of the present invention which include the incorporation of the specific emulsifiers identified above, and preferably by adjustinq the processing conditions, i.e.

the supercooling rate in the A-Unit as well as the incorporation of an extrusion valve which produces elevated pressures and sufficient shear, a stick-type margarine product essentially free of trans fatty acids or tropical oils is obtained which has all the functional benefits and physical characteristics of stick-type margarines which have trans fatty acids (i.e. partially hydrogenated oils) or tropical oils.

The following examples are provided to further illustrate the present invention.

EXAMPLE 1 A stick-type margarine was made with an emulsion having the following ingredients: Oil Phase Wt. % Co-interesterified soybean oil: 79.727 Cottonseed oil hardstock (75:25) Myverol 1807to 0.399 Lecithin 0.100 Flavor 0.052 Carotene/Vitamin A mix 0.004 Aqueous Phase Potable Water 13.452 Salted Whey 4.884 Salt 1.333 Preservative 0.049 More specifically, a blend of completely dry, refined soybean oil and refined, bleached and deodorized cottonseed oil hardstock (75:25) was co-interesterified in the presence of 0.38 sodium methylate for a period of about 30 minutes under an inert atmosphere. After achieving equilibrium, as determined by melting point, the reaction was terminated by adding 2t by wt. of a citric acid solution.The oil was then washed to remove residual by-products of the interesterification reaction and then dried under an inert atmosphere at a temperature of about 104 C.

After achieving a moisture level of < 0.1% by wt, the interesterified blend was treated with 1% acid activated bleaching earth at a temperature of about .32 C. The temperature was then raised and held at a temperature of about 104"C for a period of about 20 minutes. The interesterified blend was then cooled and filtered to remove the spent bleaching earth. Following filtering, the oil was deodorized using standard well-known conditions to remove compounds that promote unacceptable flavor and oxidative characteristics in a finished edible oil product.

The co-interesterified soybean oil: cottonseed oil hardstock blend was mixed with the other oil phase components identified above, i.e. the emulsifier (i.e.

Myverol 1807#), lecithin, coloring (beta carotene), Vitamin A, and natural and/or artificial butter flavor, in proportions to achieve the > 80% fat requirement set forth by the Standards of Identity for margarine. The water or aqueous phase, comprising potable water, salted whey (i.e. a suitable protein source), salt and preservatives, was then mixed with the oil phase at a temperature of 52 C+2 C to achieve an emulsion.

The emulsion was then pumped through the A-Unit of the previously described Votator equipment. The supply pump (5) maintained approximately 30 psi (approximately 2.07 bar) to the A-Unit feed pump. The extrusion pressure vaive was adjusted to achieve 300 psi (20 68 bar) - The system pressure of 300 psi (20 OB bar) was achieved with ar extrusion valve positioned between the A-Unit and the entrance o the crystalization tube. Oxit temperature out of the A-Unit was 9 C.

The rate was adjusted to maintain minimal temperature differential, i.e. 1"C, between the A-Unit discharge and the exit temperature of the crystallization tube which provided a residence time of about 1.6 minutes in the crystallization tube.

The resulting plasticity relative to mouthfeel, flavor release (i.e: sharpness of melting at body temperature), spreadability after 24 and 48 hrs. was determined by an expert panel to be comparable to hydrogenated stick-type margarine even though the product has more solids at lower SFI temperatures. In addition to the aforementioned characteristics of the stick-type margarine, it is noted that trans fatty acids were undetected in the margarine as was the presence of any tropical oils.

COMPARATIVE EXAMPLE 1 An emulsion was prepared as in Example 1 with the exception of the emulsifier. The Myverol 1807 was replaced with approximately 43% type mono-diglyceride at the same level.

This resulted in a product having a significant drop in plasticity. The resulting product was too soft to endure the forces involved in extruding, forming, and wrapping stick-type margarine.

COMPARATIVE EXAMPLE 2 An emulsion was prepared as in Example 1 with the exception of the processing configuration and conditions.

The extrusion valve used in the present invention was replaced with a conventional back pressure valve positioned near the exit of the A-Unit. Exit temperature out of the A-Unit was 90C. Residence time in the crystallization tube was 2 minutes.

Again, the resulting product was too soft and lacked the integrity to withstand the forces involved in extruding, forming and wrapping stick-type margarine.

EXAMPLES 2-6 stick-type margarines were prepared in accordance with Example 1 with the exception that the cointeresterified soybean oil: cottonseed oil hardstock (75:25) was replaced with the following cointeresterified domestic vegetable oil: hardstock blends: EXAMPLE CO-INTERESTERIFIED BLEND 2 soybean oil: cottonseed oil hardstock (80:20) 3 soybean oil: soybean oil hardstock (80:20) 4 soybean oil: soybean oil hardstock: cottonseed hardstock (80:19:1) 5 soybean oil: soybean oil hardstock: cottonseed hardstock (75:24:1) 6 canola: cottonseed oil hardstock (75:25) The stick-type margarines produced in Examples 2 to 6 were comparative to the final product as described in Example 1.

COMPARATIVE EXAMPLES 3 AND 4 A co-interesterified soybean oil and cottonseed oil hardstock (90:10) blend was prepared as was a Co- interesterified soybean oil and cottonseed oil hardstock (50:50) blend and were substituted into the stick-type margarine formula described in Example 1.

The (90:10) blend (Comparative Example 3) was obviously too soft to form a stick-type margarine and ar emulsion was not even attempted.

Similarly, the (50:50) blend (Comparative Example 4) was obviously too hard and too brittle to form an acceptable stick-type margarine and an emulsion was not even attempted.

The above preferred embodiments and examples are given to illustrate the scope and spirit of the present invention. The embodiments and examples described herein will make apparent, to those skilled in the art, other embodiments and examples. These other embodiments and examples are within the contemplation of the present invention. Therefore, the present invention should be limited only by the appended claims.

Claims (19)

1. A margarine and/or spread comprising an emulsion of from about 25% to about 90% by weight of a oil phase and from about 10% to about 75% by weight of an aqueous phase, wherein said oil phase comprises a co-interesterified blend comprising a domestic vegetable oil and vegetable oil hardstock in proportions by weight of from about 85:15 to about 60:40 and from about 0.2k to about 3.0k by weight of a non-plastic, fully hydrogenated, distilled monoglyceride emulsifier based upon the total weight of the margarine or spread.

2. A margarine and/or spread according to claim 1, wherein said domestic vegetable oil is selected from soybean oil, cottonseed oil, peanut oil, sesame oil, corn oil, sunflower oil, canola, safflower oil and mixtures thereof.

3. A margarine and/or spread according to claim 2, wherein said domestic vegetable oil is soybean oil or canola.

4. A margarine and/or spread according to any one of claims 1 to 3, wherein said vegetable oil hardstock is selected from soybean oil, cottonseed oil, corn oil, canola, peanut oil, sunflower oil, safflower oil, high erucic acid rapeseed oil (HEAR) and mixtures thereof.

5. A margarine and/or spread according to claim 4, wherein said vegetable oil hardstock is cottonseed oil, soybean oil or a mixture thereof.

6. A margarine and/or spread according to any one of claims 1 to 5, wherein said vegetable oil hardstock has an iodine value of less than or equal to 5.

7. A margarine and/or spread according to any one of claims 1 to 6, wherein the proportion is from about 80:20 to 70 :30.

8. A margarine and/or spread according to any one of claims 1 to 7, wherein said non-plastic fully hydrogenated distilled monoglyceride emulsifier is present in an amount of from about 0.3k to about 1.0% by weight.

9. A margarine and/or spread according to any one of claims 1 to 8, wherein said oil phase comprises at least 80% by weight of the emulsion.

10. A process for making an emulsified stick-type margarine or spread comprising the steps of: (a) forming an emulsion of from about 25% to 90% by weight of an oil phase and from about 10% to about 75% of an aqueous phase, wherein said oil phase comprises a cointeresterified blend of a domestic vegetable oil and vegetable oil hardstock in proportions by weight of from about 85:15 to about 60::40, and from about 0.2k to about 3.0% by weight of a non-plastic, fully hydrogenated, distilled, monoglyceride emulsifier based upon the total weight of the margarine or spread; (b) feeding said emulsion into an A-Unit; (c) supercooling said emulsion in said A-Unit; (d) discharging the supercooled emulsion from the A-Unit through an extrusion valve which functions to maintain sufficient pressure and shear; (e) feeding said emulsion into a crystallization tube; and (f) forming and packing the emulsion in stick-type form.

11. A process according to claim 10, wherein said extrusion valve is positioned between the exit of the A-Unit and the entrance to the crystallization tube.

12. A process according to claim 10 or claim 11, wherein said domestic vegetable oil is selected from soybean oil, cottonseed oil, peanut oil, sesame oil, corn oil, sunflower oil, canola, safflower oil and mixtures thereof.

13. A process according to claim 12, wherein said domestic vegetable oil is soybean oil or canola.

14. A process according to any one of claims 10 to 13, wherein said vegetable oil hardstock is selected from soybean oil, cottonseed oil, corn oil, canola, peanut oil, sunflower oil, safflower oil, high erucic acid rapeseed oil (HEAR) and mixtures thereof.

15. A process according to claim 14, wherein said vegetable oil hardstock is cottonseed oil, soybean oil or a mixture thereof.

16. A process according to any one of claims 10 to 15, wherein said vegetable oil hardstock has an iodine value of less than or equal to 5.

17. A process according to any one of claims 10 to 16, wherein the proportion is from 80:20 to 70:30.

18. A process according to any one of claims 10 to 17, wherein said non-plastic fully hydrogenated distilled monoglyceride is present in an amount of from about 0.3% to about 1.0% by weight.

19. A process according to any one of claims 10 to 18, wherein said oil phase comprises at least 80k by weight of the emulsion.