IE922194A1 - Gelled food products - Google Patents

Abstract

A gelled food product containing a microparticulate suspension of an edible food ingredient, such as fats/oils, entrapped in a heat-set protein gel, such as egg white, blood serum or whey, is prepared.

Description

GELLED POOD PRODUCTS This invention relates to the preparation of microparticulate suspensions stabilised in heat-set gels for food applications.

Thermally induced gelation oocmt when restricted protein unfolding yields soluble polypeptide segments capable of specific interactions which form a well ordered three-dimensional network able to entrap large amounts of water. The ability of unfolded proteins to associate and form a gel depends upon the protein, its amino add composition and molecular weight, the protein concentration, heating temperatures and rates and a critical balance between attractive and repulsive forces.

Cross-linking is essential for gel formation; hydrogen bonding, ionic end hydrophobic interactions and covalent disulphide bonding are critical intmnolecular interactions for gel formation. The difference observed between globular proteins in their ability to form gels reflects different types of protein-protein interactions and the number and extent of interactive sites in the protein aggregates.

Milk proteins undergo gelation after several types of treatment but only those known as the whey proteins are capable of heat-induced gelation. Beta* lactoglobulin is considered to be the most important whey protein for gelation since it ia capable of forming uniform gels of high breaking strength due largely to its ready ability to eater into disulphide-mediated croaa-linking upon heating.

Egg white proteins are widely used in food preparations requiring high gel strength and heat-set properties, although the bonding is esdustvely non30 covalent. Special conditions in terms of electrostatic repulsion between the protein molecules are required for gelation and may be achieved by manipulating the pH, type of salt and salt concentration. -2Blood plasma proteins are often incorporated into manufactured meat products to effect improvement in water holding capacity through formation of a gelled structure.

The use cf gellable proteins in food systems has been described widely a> thickening, binding and water binding agantt.

US Patent No. 3392373 described the replacement of egg yob in salad dressings and mayonnaises by partly thermally denatured whey proteins acting as thickener.

Emulsions of greater firmness were achieved by the process described in Australian Patent No. 578379, which involved emulsifying a Upidic stibstaace with gellable whey protein, such as whey protein concentrate, and beating strongly. For a given protein concentration, the viscosity of the emulsions obtained after emulsification increased consideraWy with the lipid concentration. The protein-to-lipid ratio was selected according to the nature, firmness of tmture and nutritional properties required in foe products. The firmness of products was also influenced by the heating temperature. Far a cream type product, heating at a temperature of the order of 90 *C at atmospheric pressure for a treatment time of about 15 minutes was required. Tb obtain a gel like an egg-custard, it was preferred to place foe emulsion into containers which were hermetically sealed, the heat treatment being then applied in an autoclave at 115 *C for 15 to 30 minutes. The texture of the product was also determined by the diameter distribution of foe oil globules; only if it was narrow reflecting intensive homogenisation, was a firm gel obtainable. Compressive forces causing a rupture of foe gel were in the ranges 02 -1.0 (very soft), 1.0 - 2.0 (firm) and 2J0 - 4.0 (very firm) N/cnA We have now found that by selection of appropriate heat-galling protein and with appropriate selection and treatment of certain mlcroperticulate food ingredients, gelled products may be obtained in whidi contain the -3microparticulate ingredients in suspension and which are of much greater firmness than the products obtained by the proce» of Australian Patent No. 578,879.

The microparticulate suspension may consist ia whole or part rt an emulsion of a fat or oiL The gel strength of the gelled food products described by this invention may be modulated by the concentration of the protein and other factors.

However, while the products arising horn the process described in Australian Patent No. 578379 show viscosities which increase with lipkl or other included microparticulate substance up to a level dependent on the nature of the substance.

The difference between die two processes is further illustrated by the fact that to obtain even a soft, egg custard-like gel by the process of Australian Patent No. 578379, required heating emulsions in hermetically sealed containers in an autoclave at 115 C whereas much lower temperatures can be used in the practice of this invention.

Using die process of this invention a wide range of new products including low-fat” products with attractive texture may be prepared utilising various combinations of heat-geilsble proteins, at varying concentrations, and a variety of microparticulate components. Further variation may be obtained in the food product by addition of soluble substances including salts, colorants, fiawourants and sweeteners in die protein solution prior to gelation.

In our International patent application No. PCT/AU88/00141, Whey Protein Fractions” we describe a product, die beta-fraction, which by virtue of its beta-lactoglobulin content, demonstrates greater gel strength properties and versatility than other whey protein or other food protein products. -4We have now discovered in particular that we can disperse fats/ofls, in an emulsified state, in beta-fraction solution and subsequently The* (entrap) the fat droplets (microparticles) by heating and galling the beta-fraction protein around them. At a level of fat/oil around 5-10% w/w in the gel the product has “fat-hke* qualities (mouthfeel, opacity, juidneas etc), in other words it behaves tike a low-fat* fat. Surprisingly In (or below) this fat concent range die dispersed fat has little effect on the strength of the gel, and thus rheological characteristics can be largely determined by the protein content and solvent composition. The gel holds a large quantity of water tightly and if the fat is wen homogeniaod there is no free fat leakage. The product esn be sliced, (heed, chopped or minced and.because the gel is formed by heating at around 90 *C this Tow-fat* fat can be used as fat replacement in comminuted products that are to be heated.

IS According to one aspect of the present invention, there is provided a gelled food product comprising a microparticulate suspension of an edible food ingredient in a heat-set geL In another aspect the invention provides a gelled food product comprising an enriched beta-lactoglobulin, more preferably the beta fraction.

According to a further aspect of the present invention, a process for the preparation of a microparticulate suspensions entrapped in heat-set gel comprises the seeps of: (a) preparing an aqueous microparticulate suspension or dispersion of at least one edible food ingredient which is insoluble in water or aqueous solutions; (b) mixing the microparticulate suspension or dispersion from (a) with a protein capable of forming a uniform gel when heated, the proportions of said suspension or dispersion and the protein being suitable to form -5the desired product; (¢) heat treating the mixture from (b) to form a heat-set gel containing «aid suspension or dispersion; (d) cooling the heat-gelled mixture from (c) to ambient or sub-ambient temperature.

The preferred parameters for the steps of the process of the imeatiao will now be discussed in more detail The micraparticulate suspension or dispersion of edible food ingredients in the aqueous medium may be prepared by any suitable process, eg. by homogenisation so diet the particle size is reduced to an effective diameter IS within the range 100 to lOQflOO nanometers. The site of die dispersed particle may be optimised in relation to their buoyancy in, and interaction with the gellable protein solution when the two are mixed.

Step (b) involves selection erf a thermally gellable protein which should dissolve or disperse in aa aqueous medium at a concentration in the range of 10 to 150 g/L of true protein. To be considered suitable for use in the present process a protein should have a gel breaking strength at least equal to that cf gelled egg white with an equivalent protein concentration when heated at 90*C for 30 minutes. The protein maybe in its natural state or isolated by any suitable method which enables its heat gelation properties to be retained. For example, suitable proteins may be sourced from egg white, blood serum or whey, or mixtures thereof. Enriched beca-lactogfobufin in the form of betafraction prepared according to Peirce (198S), is die most preferred protein.

[Note: Rtf erases an listed at the end cf this description.) The protein may be added to the microparticulate suspension or * 6dlsperston in the solid or liquid state. The proteins may be dissolved or dispersed In water or any other suitable aqueous or nnraqueous liquid before mixing with the microparticulate suspension or dispersion. The gel strength may be modified by adjustment of the concentration of protein.

Also in step (b) other components soluble in an aqueous medium may be added to provide modulation of the strength of the geOed product after heating or sensory qualities induding saltiness, sweetness, colour and flavour.

In the instance of enriched beta-lactoglobulin as gellable protein the strength of the heat-set gel hasbeen shown to be dependent on the pH, the sodium ion content and the cakaumion content (MuhihiU and KinseDa,1987). Other ions may also be Influential, for example potassium and magnesium ions. Such additional components may be added as such at step (b) or dissolved or dispersed with the protein before addition.

In die mixing operatic», die usual approach is to mix a proportion of the microparticulate suspension from (a) with the protein (in solid form or as a solution or dispersion) so as to provide a maximum volume of suspended microparticulates of about 30% by volume and to achieve a geliable protein concentration in the range 10 to 150 g/L of true protein. Preferably die volume of suspended microparticulate is less than 15% and the protein content corresponds to between 50 and 110 g/L of true protein. Generally incorporation of air should be avoided, unless air bubbles are a specific requirement in the final product In step (c), the mixture from step (b) is heat treated, preferably at a temperature in the range 25 to 100 *C feu* from 5 to 120 minutes, more preferably in the range 60 to 90’C for from 15 to 60 minutes. After the beat treatment die mixture is cooled to ambient temperature or below (step (d)).

One suitable heat treatment method is to place die solution in a vessel which is preferably dosed but not hermetically sealed, and which, if required, may be in the form of a moulding device. Heat treatment may also be carried out by •7any other suitable method.

When the gellable protein it natorel egg white, the gelled product after heating without the microparticulate suspension, it white and opaque; consequently the product containing suspended microparticles win also be opaque. However, contfitions of pH and ionic content have been described which allow the major protein of egg white ovalbumin, to be heat-set as either transparent or opaque gels (Hegg et al 1979).

The form of heat-induced protein gds from blood plasna proteins may vary according to the level ofprotein fractionation of the product While gelled whole plasma protein is opaque, conditions have been described in which blood serum albumin gels may be transparent (Yasuda, stot 1986). A comparison of the properties of heat-induoed gels from egg albumin and bovine plasma proteins showed that plasma proteins produced a gel which was strong and elastic whereas egg albumin protein gels were fragile and brittle (Hickson, et al, 1982).

When the gellable protein is an enriched beta-lactogjobulin whey protein fraction, the gelled product after heating in the absence of a microparticulate suspension may be dear or opaque dependent upon the oaooentration of metal ions sudi as sodium and calcium ions (MuMhill dt Kinsdla, 1987; Pearce, 1991). Consequently conditions of ionic content in the protein solution produoed in the second step of the prooess may be selected so that the nticroparticulate suspension may be stabilised in a dear or opaque medium. The size and content of microperticulate component may also affect the appearanoe of die gelled product as, for example, when fat or oil is finely dispersed in the gel the product is white and opaque.

The nature of die selected mkrcparticulate component may demand specific pretreatment in the preparation of the dispersion (step (a)) prior to mixing with the geUable protein solution. For example, in the dispersion of ,E 922194 -8· fats or oils into a mfcroparticulate state, homogenisation in the presence of an emulsifying agent may be necessary. The emulsifier may be the same protein as the geQable protein, if the latter displays good emulsifying properties in addition to high performance gelation. Alternatively the emulsifier may be another protein, provided that it does not interact adversely with the gellable protein and reduce its gelling performance, or it may be a naturallyoocuring emulsifying substance, a chemical emulsifier, or a combination of these, provided that it does not interact detrimentally with the gellable protein.

Where additional solublecomponents are disserved in the gellable protein solution their nature and content should be such that the gelling performance of die gellable protein remains satisfactory with regard to product requirements. The breaking strength cf heat-set protein gels is influenced by pH and therefore, addition of acid or alkali (usually food grade) may be IS necessary to obtain the desired gelation performance.

To provide the desired organoleptic properties in the product, salt and/or suitable sweeteners, flavourants and colorants may be added together with the gellable protein in step (b).

Alternatively or additionally, in a product In which the microparticulate suspension b an emulsified lipid, the sensory properties of the gelled food product of the invention may be modified, for example to simulate the sensory qualities of fat For example, the concent and composition of emulsified fat or oil ic the microparticulate suspension may be varied to allow selection of the nature of the gelled food product when used in a fat replacer. In addition lipid-soluble flavourants and/or colorants may be included in the suspension in step (a). The physical properties ol gel strength, texture and opacity of the gelled food product may also be varied by adjustment of the protein and mineral contents.

When required, microbubbles of gas may be included or generated in -9the gellable mixture so that when subiUsed by heat-setting, the gel may have an aerated, spongy texture.

The invention is further described and illustrated by the following non5 limiting examples. These examples demonstrate, freer alia the following features of the products of the invention. 1. The firmness of the product is determined by the concentration of gellable protein. _ 2. The firmness of the product is independent of the concentration of dispersed microparticulates. 3. When an oil is the dispersed microparticulate, the firmness of the product is independent of the source sad physical characteristics of the oil. 4. The clarity of gelled product prepared from ^fraction as the gellahle protein is modulated by mineral content. •10EXAMPLE1.

This example shows that the firmness of the product is determined by the concentration of gellable protein. a) In the absence ef suspended ndmpartiadates Aqueous solutions of β-fracdon, a product derived from cheese whey (obtained by a thermal fractionation process and containing 75% protein on a dry matter basis and 65% of the protein being p-lactogfobulitt) were prepared at pH 6.8 at different protein concentrations in the range 53 to 9.0% w/w.

Aliquots (50mL) of ^fraction iplutions were placed gad sealed to dialysis tubing bags having adiameter of 30mm. Each bag containing protein solution was heaved at 90 *C for 30 minutes and cooled to running tap-water for 1 hour. Slices 30mm in length were cut from the gelled protein solution and evaluated for gel breaking strength using an Instron Universal Testing Machine to IS compressive mode at 20*C with a cross-head velocity of SQttm/min and fitted with a 10mm diameter circular disc probe applied to the centre of the cut surface. The results are shown in Table 1. Values reported are the mean of three determinations.

TABLE 1: Protein Concentration Gel Breaking Strength (% w/w) ω 53 0 6j0 0 63 0 7Λ 112 73 218 &0 424 83 632 9J0 TK> -11 b) In the presence cf suspended miaopardadates A microparticulate dispersion of butter oil in water was prepared by two stage homogenisation at 172 and 3J MPa at SO’C, using ^fraction to stabilise the emulsion at an oiLprotein ration of 10:1. The dispetsion was mixed with solutions of ^fraction (as in Example 1 (a)) to yield a final concentration in the range 7.0 to 11.0% w/w of protein and a final oB content of 5% w/w. Aliquots of each mixture were heated to stabilise the mkroperticnlate dispersion in a geOed protean matrix under conditions as used in Example 1 (a). Gel breaking strength was measured as in Example 1 (a). Results are shown in Table 2. ..

TABLE 2: Protein Concentration in Mixture Containing 5% Oil Dispersion (% w/w) Gel Breaking Strength (i) 7Λ 160 9.4 570 11Ό 845 EXAMPLE 2.

This example shows that the firmness of the product in general is independent of the concentration of dispersed microparticulates but this may not apply at high levels of mkroparticulates. a) Buttered dispersion A miaoparticulate dispersion of butter oil was prepared as in Example 1 (b). Aliquots of the dispersion were mixed with ^fraction solution SO that the final protein concentration was 9.4% w/w and the final oil concentration in the range 1.0 to 9.0% w/w. Portions of each mixture were heated to stabilise ίΕ 922194 - 12the microparticulate dispersion in a gelled protein matrix under conditions as used in Example 1 (a). Oel breaking strength was measured as in Example 1 (a). Results are shown m TaWe 3.

TABLE 3; Final Concentration of Oil Dispersed in ^fraction Solution at 9.4% w/w Protein (% w/w) Gel Breaking Strength U) -. L0 435 ..... 2.0 450 3.0 435 4.0 425 6.0 505 9.0 460 h) Cocoa powder dispersion A microparticulate dispersion of cocoa powder was prepared by vigorous stirring erf the powder in water. Aliquots of the dispersion were mixed with p-firaction solution so that the final protein concentration was 9.4% w/w and the final cocoa powder concentration in the range 1 to 5% w/w. Portions of each mixture were heated to stabilise the microparticulate dispersion in a gelled protein matrix under conditions as used in Example 1 (a). Gel breaking soength was measured as in Example 1 (a). Resulo are shown in Table 4. -13· TABLE 4: Final Concentration of Cocoa Powder dispenedin jHr action Solution at 9.4% w/w Protein (% w/w) Gel breaking strength (ί) 1.0 510 3.0 505 5.0 770 EXAMPLE 3. _ _ This example shows that when an oil is the dispersed microparticulate, the firmness of die product is independent of die source and physical characteristics of die oil.

Microparticulate dispersions of oils and fats were prepared as in 15 Example 1(b). Afiquott of each oil or fat dispersion were mixed with pfractkm solution so that the final concentration of protein was 9.4% w/w and final oil/fat concentration was 5 % */*. Portima of each mixture were heated to stabilise die microparticulate dispersion in a gelled protein matrix under conditions as used in Example 1 (a). Get breaking strength was measured as in Example 1 (a). Results are shown in Table 5.

TABLES: Qil/Fat used at 5% w/w in Gel Breaking Strength p-fracdon Solution at 9.4% w/w Protein ω butter oil 570 coooa butter 515 pork lard 595 sunflower oil 570 ·14· EXAMPLE 4.

This example shows that the clarity of gelled product prepared from p· fraction as the gellable protein is modulated by mineral oonteat. a) In the absence Aqueous solutions ot p-fracdon were prepared as in Example 1 (a). Ax 9A% srhr protein concentration the concomitant concentration of sodium and calcium chlorides were equivalent to 0.004 and 0ί064% w/w respectively. Sodium chloride and calcium chloride were added to aliquots of the p-fracdon to achieve concentrations in tbejrange 0L004JO 0200% w/w sodium chloride and 0.064 to 0.100% w/w calcium chloride. A portion of each p-fracdon solution was heated to effect gelation of protein as described in Example 1 (a). Gel breaking strength was measured as In Example 1 (a). Clarity of gels was determined using a Minolta Chromameter on freshly cut slices of gelled product and recorded aa L* values, a measure of reflectance. Results are shown in Tables 6 and 7.

TABLES: Gel Breaking Strength (g) 20 Sodium Chloride Concentration % Q004 0.05 0.1 0.15 02 sr/st Calcium Chloride Concentration % w/w 0.064 570 510 540 580 550 25 0.070 555 od 545 nd 450 0.080 540 nd 575 ad 440 0.090 545 nd 535 ad 300 0.100 475 nd 355 nd 190 n3r^Mnou3etennwe7 -15TABLE7: Reflectance *(L value) Sodium Chloride Concentration % w/w 0.004 0.100 0200 5 Calcium Chloride Concentration % w/w 0Ό64 47.9 61-5 752 0.070 49.9 652 77.7 0.060 563 69.9 76.7 0.090 “ 63.6 /74.0 76t4 10 0.100 643 773 763 • L (water) 305 L (homogenized milk) = 923 EXAMPLES.

This example shows that mfcroparticulate suspensions may be stabilised in heat-set ^-fraction gel sweetened with sucrose. (a) In Ae absence cf Aspersed micrapartiaiates An aqueous solution of ^fraction was prepared as in Example 1 (a).

Aliquots of this rotation were mixed with aliquots of sucrose solution so that the final protein concentration was 9A% w/w and the final sneroee concentration in the range 4 to 12% w/w. Portions cf each mixture were heated to effect gelation of the protein as described in Example 1 (a). Gel breaking strength was measured as in Example 1 (a). Results are shown in Table & (b) In Ae presence cf Aspersed mlcrupariiadates A mfcroparticulate suspension of cocoa butter was prepared as in Example 1(b). Aliquots of the dispersion were mixed with ^fraction solution -16and with sucrose solution so that the final concentration of protein was 9.4% w/w, so that the final concentration cf oil was 5.0% w/w and that the final sucrose concentration was in the range 4 to 12% w/w. Portions cf each mixture were heated to stabilise the microparticulate suspension in a sweetened gel protein mixture under conditions as used in Example 1(a). Gel breaking strength was measured as in Example 1 (a). Results are shown in Table 9.

TARCJE* Sucrose concentration itf p-firactitm~ ‘ · ' ' Ϊ, » solution containing 9.4% w/w protein (% w/w) Gel Breaking Strength ¢8) 4 540 8 560 15 12 520 TABLE 9: Sucrose concentration in mixture containing 9.4% w/w ^fraction and 5.0% w/w cocoa butter in dispersion (% w/w) Gel Breaking Strength fc> 4 500 8 520 25 12 520 -17EXAMPLE6.

This example shows that micropartKoiate suspensions may be stabilised in heat-set gels of proteins derived from various sources. (of Gdatton cf egg white protein in the absence of disponed ndcropartiaiates Atpsoaos solutions of egg white protein were prepared from commercial, spray dried powder ax different concentrations of protein and at pH 6B as in Example 1 (a). Aliquots of protein solutions were heated to effect gelation as described in Example 1 (a). Gel breaking strength was measured as in Example 1 (a). Results are shown in Table 10.

V ..... -- - TABLE IQ; Concentration of egg white protein in solution at pH 6.8 (%w/w) Gel Breaking Strength ¢8) 7.0 85 9.4 195 11.0 290 (b) Gelation cf blood plasma, protein tn die absence cf dispersed micnpartlatate? Atfseonn solutions of blood plasma proteins were prepared from commercial, tpny dried powder at different concentrations cf protein anti at pH &8 as in Example 1 (a). Aliquots of protein solutions were heated to effect gelation as described in Example 1 (a). Gel breaking strength was measured as in Example 1 (a). Results are shown in Table 11.

TABLE lli •18- Concentration of blood plasma proteins in solution at pH &8 (%w/w) Gel Breaking Strength (8) 7Λ 235 9.4 510 11.0 690 (c) In die presence ef dispersed ndcrapartiadaies A mkroparticulate dispersion of butter oil in water was prepared aa in Example 1(b). Aliquots of this dispersion were mixed with aqueous solutions of ^fraction, egg white protein (prepared using spray dried egg white powder) or blood plasma protein (prepared from Wood plasma protein powder) to achieve final concentrations dt protein of 9A% veto and final concentrations of oil of 5% w/w. A portion of each mixture was heated to stabilise the miaoparticulate suspension in a gelled protein matrix under the conditions used in Example 1 (a). Gel breaking strength was measured as in Example 1 (a). Results are presented in Table 12.

TABLE 12: Source of Gellable Protein in 9A% w/er protein with various fat contents Gel Breaking Strength ω Butter oil content % w/w 3 6 9 β-fraction from cheese whey 435 505 460 Egg white 190 210 195 Blood plasma 690 675 700 ·»· The following example» show the ose of the gelled food products of the Invention as Tat replace»* In the preparation of manufactured food items, namely Tow-fat meat products.

EXAMPLE 7 Manufacture of Itwftat fanlfurterl wiener type sausage A frankfurter/wiener-type sausage traditionally contains lean meat and fat in a finely comminuted and uniformly emulsified form with a typical fat content of about 22%. Using a gelled food product in accordance with die invention as fat replacer, aa in thia Example, the product had a fat content of M%.

The sausage mix containing the gelled food product was processed using traditional technology and provided a product which was satisfactory with respect to fat distribution, texture and other sensory attributes, but with a much lower fat content than the traditional product (a) Preparation of gelled food product as fat rcptocer Using the general method set out in Example 1, a gelled food product containing microparticulate pork lard was prepared whfc a beta-fraction protein content of 8% w/w and a fat content (pork laid) of 12% w/w to provide the required texture and sensory quality in the final product (b) Preparation cf sausage Competition beef (95% cl)’ pork (90% cl) fat replacer3 ice 30 sodium chloride sodium nitrite 6.0 kg 4.0 kg 10 kg 13 kg 270 g 16 sodium tripolypbosphate 40g seasoning 68g ascorbic add 13 g garlic 15 g beef «attract 20 g Notes: 1. cl chemical lean 2. Le. the gelled food product described in (a) above W Method . .... _ . _ The beef and porkwere chilled to 4-5 *C and minced separately through a 10mm plate.

Prior rc the addition of the fat replacer, it was frozen to -20’G The minced beef, sodium chloride, sodium nitrite and sodium tripotypbosphate were placed in a silent cotter which was nm at high speed for five revolutions of the bowl prior to the addition of half of the frozen fat replacer. After an additional IS revolutions the minced pork plus the remainder of the fat repiacer was incorporated together with the ascorbic add, eoosomnfc garlic and beef extract The emulsion was rhoppftri in the cutler until it reached a temperature of 14’C The emulsion was filled into 24mm diameter sheep casings using a vacuum staffer. The frankfurters were surface dried in a cooker/smokehouse at 50 *C and then smoked at 6$*C for 15 hours followed by cooking to an internal temperature of 72 *G When cooking was complete the frankfurters were showered to oool diem and then chilled overnight at 5 *G EXAMPLES Manufacture of torfat Stnuburg xuoage A Strasburg sausage traditionally contains coarsely chopped meat and fat distributed in a uniform meat and fat emulsion with a typical total fat content of about 30%. In this Example both chopped and emulsified fat have •Ε 922194 -21 been replaced by the gelled food product of the invention to gwe a product containing 7% fat.

The sausage mix containing gelled food product was processed into Strasburg sausage using traditional technology and resulted in a product with the appearance cf a traditional Strasburg sausage and a satisfactory texture and other sensory attributes.

The fat replacer used was prepared as described in Example 7.

Composition beef (95% cJ.) 23 kg poit(90%c±) 2.0 kg fat replacer 325 kg sodium chloride 155 g sodium nitrite 1« sodium tripoiypboephate 24g seasonings 84g ascorbic add Bg beef extract 20 g Method The beef and pork were chWed to 5*C and minced separately through a 10mm plate. The fat replacer for the emulsion phase (125kg) was frozen to -20 *C. The fat repiacer to be used in the non-emulsified form (2.0kg) was chopped from a chilled state at 5’C The beef, sodium chloride, sodium nitrite and sodium tripolyphosphate were chopped in a silent cutter at high speed for 10 revolutions of the bowi The frozen fat replacer was added and chopped for a farther 30 revolutions of the bowl. Seasoning, ascorbic add and beef extract were added and chopped until the temperature of the emulsion was 10’C Coarsely cut (l-5mm) fat -22replacer and minced pork were added and mixed into the emulsion in the cutter at low speed for two revolutions of the bowl.

The product was filled into 90knm diameter, moisture impermeable 5 casings and cooked to an internal temperature of 68 *C After showering to cool the product, it was «billed to S*C IE 922194 -23REFERENCES HEGG, PO, MARTENS, H. & LOFQUBT, B. (1979) Λ Set Food Agric. 34 981-993.

HICKSON, D.W„ DHL, CW, MORGAN, R.G, SWEAT, VJ5., SUTER, DA A CARPENTER, ZJ- (1982) /. Food ScL 47,783-791.

MULVIHILI, DAL and X3NSELLA, LE. (1987) Food TecknoL 41, 10 102-111.

PEARCE, RJ. (1988) New Zealand Patent No. 224,615; Australian Patent Να 616,411; International Patent Application Να PCT/AU88/00141.

PEARCE, RJ. (1991) Food Res. Qtfy. SI, 74-85.

YASUDA K., NAKAMURA R. A HAYKAWA S. (1988) 7. Food ScL

Claims (21)

1. A gelled food product characterised in that it comprises a microparticulate suspension of an edible food ingredient in a beat-set geL X A food product as claimed in Claim 1, characterised in that the edible food ingredient is a fat or ofl, or a mixture thereof.

2. 3. A food product as claimed in Claim 1 or Claim 2, characterised in that 10 the gel is farmed from protein.

3. 4. A food product as claimed in Claim 3, characterised in that the protein la sourced from egg white, blood serum, dairy whey or mixtures thereof. 15

4. 5. A food product as claimed in Claim 4, characterised in that the protein is enriched beta-lactogiobulin in the form of beta-fraction.

5. 6. A process for the preparation of a akroparticulare suspension entrapped in heat-set gels characterised by the steps of: (a) preparing an aqueous microparticulate suspension or dispeisfon of at least one edible food ingredient which is insoluble in water or aqueous solutions; 25 (b) mixing the microparticulate suspension or dispersion from (a) with a protein capable of forming a uniform gel when heated, the proportions of said suspension or dispersion and the protein being suitable to form foe desired product; 30 (c) heat treating the mixture from (b) to form a gel; (d) cooling the heat-gelled mixture from (c) to ambient or sub-ambient -25temperature.

6. 7. A process as claimed in Claim 6, characterised in that the protein added in step (b) is in solid form.

7. 8. A process as claimed in Claim 6, characterised in that the protein added in step (b) fa in the form of a solution or dispersion.

8. 9. A process as claimed in any one of Claim 6 to 8, characterised in that

9. 10 the amount of protein added in step (b) fa sufficient to provide a gellable protein concentration in the range-10 to 150 g/L of true protein. 10. A process as claimed in any one ot Claime 6 to 9, characterised in that the volume of suspended micropartides is not greater than 30% by volume.

10. 11. A process « claimed in any one of Claims 6 to 10, characterised in that the volume of micropartides fa less than 15% by volume and the protein content corresponds to from 50 to 110 g/L of true protein. 20

11. 12. A process as claimed in any one of Claims 6 to 11, characterised in that the protein has a gel breaking strength at least equal to that of gelled egg white with an equivalent protein concentration when heated at 90 *C for 30 minutes. 25

12. 13. A process as claimed in Claim 12, characterised in that foe protein fa sourced from egg white, blood serum, dairy whey or mixtures thereof.

13. 14. A process as claimed in claim 13, characterised in that foe protein fa enriched beta-lactoglobulin in foe form of beta-fraction.

14. 15. A process as claimed in any one of Claims 6 to 14, characterised fax that the heat treatment in step (c) is carried out at a temperature in the range of -2625 to 1WC for from 5 to 120 minutes.

15. 16. A process « claimed in Claim 15, characterised in that die heat treatment is carried out at 60 to 90 *C for 15 to 60 minutes.

16. 17. A food or food material characterised in that it contains a gelled food product as claimed in any one of Qaims 1 to 5.

17. 18. A gelled food product according to claim 1, substantially as hereinbefore described and exemplified.

18. 19. A process according to claim 6, for the preparation of a microparticulate suspension entrapped in heat-set gels, substantially as hereinbefore described and exemplified.

19. 20. A microparticulate suspension entrapped in heat-set gels, whenever prepared by a process claimed in claim 6-16 or 19.

20.

21. A food or food material according to claim 17, substantially as hereinbefore described and exemplified.