Introduction

The invention relates to a method for preventing the denaturation of protein during frozen storage. In particular this invention relates to a cryoprotective composition to preserve the biological activity of proteins during frozen storage.

Freezing is a widely used and highly effective means for long-term preservation of products, including food products. Freezing prevents microbial spoilage and minimises the rate of chemical and biochemical reactions contributing to quality deterioration. However, frozen storage and inappropriate storage conditions can result in profound effects on chemical and structural properties of food products. These changes are usually associated with proteins becoming denatured and as a result, there is a loss in quality of the end-products (Herrera and Mackie, 2004; Mackie, 1993; Barbut and Mittal, 1991).

Frozen blocks of beef, pork, poultry and fish are common starting materials in the food industry; therefore any detrimental changes to the starting material as a result of freezing will have a profound effect on processors along the production chain. This includes the economic aspect, which is mainly related to the resulting weight loss that must be minimised and the quality aspect where organoleptic properties are considered. One of the key issues in maintaining the shelf life and other quality attributes of frozen muscle systems is ice crystallisation. Quality changes during the freezing process are related to the way in which ice crystals are made to grow. During frozen storage, crystals undergo metamorphic changes. Crystal growth often inflicts damage during freezing. Recrystallisation occurs because systems tend to move toward a state of equilibrium where free energy is minimised and the chemical potential is equalised among all phases. After freezing, many solutes may be supersaturated in the unfrozen phase. In time, these may crystallise or precipitate. This will change the relative amounts of solutes and the

actual concentration of solutes. Therefore, the ionic strength can change, and pH can change due to changing ratios of buffer components. These factors also affect the stability of other molecules, and changes in characteristics of molecules in solution can occur.

A number of mechanisms have been proposed for freezing injury and cryoprotection. Hypotheses involve the concept that freezing damage occurs because important nonaqueous components are inadequately protected from water. Bound water in the form of lattices seems to be essential to cell integrity, especially protein structure and function. The cellular morphological changes during freezing and the physical events of crystallisation suggest that cellular membranes are preserved during slow-freezing because of increased stability of the lattice structure. Death in freezing seems to occur primarily as a result of extraction of bound water from vital cellular structures. The extracted water, incorporated into growing ice crystals, leaves proteins dehydrated and denatured. During rapid freezing, intracellular ice formation consumes not only the free water but also portions of the bound water, thereby weakening the lattice structures

According to Herrera and Mackie (2004), a number of compounds have been tested to protect muscle proteins from denaturation and so improve the technological properties of frozen muscle tissue. Carbohydrates, polyols and some amino acids and related compounds have shown the highest cryoprotective effectiveness (Matsumoto, 1980; Park 1994). It has been suggested that the most effective cryoprotectants for myofibrillar proteins are carbohydrates (Tomaniak et al., 1998). However, their application is limited by their sweetness. The intensity of sweetness is different for each of these substances and the more complex sensoric sensations (sweetness and off-tastes) are also different. Disaccharides such as sucrose and trehalose are natural cryoprotectants. Trehalose is a particularly attractive cryoprotectant because it has actually been isolated from plants and animals that remain in a state of suspended animation during periods of drought. Trehalose has been shown to be an effective protectant for variety of biological materials. Trehalose has the ability to form glasses, which have very high viscosity and low

mobility, leading to the increased stability of the preserved material. Apart from the formation of a glass the interaction between the sugar and the polar group in proteins and phospholipids appears to be essential for stabilising biomaterials of various composition during freezing (Patist and Zoerb, 2005). These authors postulate that trehalose has two mechanisms in preserving biomaterials. Firstly, trehalose has a very high glass transition temperature (Tg), as a result during freezing the proteins are physically constrained on a molecular scale and hence denaturation cannot occur. Secondly, trehalose is capable of forming strong hydrogen bonds with the polar group of the biomolecules, thus replacing the water molecules at the membrane-fluid interface and maintaining the head groups at their hydrated position upon drying. In this way, it is suggested that trehalose prevents the phase transition of the biomembrane from lamellar to gel phase and its accompanying leakage upon rehydration (Patist and Zoerb, 2005). Kowata et al. (2004) describe the use of sorbitol and/or trehalose as inhibitory agents for protein denaturation in kneaded meat.

The so-called "cryostabilisation" theory is based upon the ability of high molecular weight solutes to raise the glass transition temperature (Tg) of a solution (Park, 1994). At higher concentrations of solution, the Tg occurs at temperatures above freezing. Cryostabilistaion of proteins involves addition of a solute, such as trehalose, to raise the Tg to a temperature above the storage temperature, ensuring that the system is in the glass state. This effectively minimises the freeze-induced deteriorative process including ice crystal formation, since water is immobilised in the glass structure (Park, 1994). Lanier and McDonald (1992) concluded that cryostabilisers act to enmesh the protein in a glass where all deteriorative processes are greatly slowed.

Park et al., 1988; Sultanbawa and Li-Chan, 1998; Synch et al., 1990; Synch et al., 1991 describe the use of polydextrose for cryoprotective purposes. Lanier and Akahane (1986) describe the use of polydextrose as a cryoprotectant in comminuted meat.

Phosphates are commonly used in the food industry as acidity regulators, stabilisers, emulsifying salts and raising agents. They are extensively use in the meat industry as

acidity regulators and stabilisers. Both Trout and Schmidt (1983) and Knipe, (2004) describe the use of phosphates in meat products. Park et al. (1988) reported that phosphates reduced freeze-induced aggregation in stored fish myofibrils.

Hitherto, no single or combination of ingredients has shown any cryoprotective effects markedly better that the commercially practised combination of sucrose and sorbitol. Many other ingredients present problems in terms of cost, amount used and the method in which then have to be applied to the muscle system. It is the objective of this present invention to provide a cryoprotective composition which will address these issues.

Statements of Invention

According to the invention there is provided a cryoprotective composition comprising:

a disaccharide;

a non- starch polysaccharide; and

a source of phosphate ions.

In one embodiment the source of phosphate ions is a pyrophosphate ion source.

In one embodiment the disaccharide is selected from one or more of trehalose and lactose.

In one embodiment the non-starch polysaccharide is selected from one or more of polydextrose, inulin and oligofructose.

The source of phosphate ions may comprise at least one polyphosphate such as sodium and/or potassium tripolyphosphate.

In one embodiment the composition further comprises a source of chloride ions. The source of chloride may be sodium chloride and/or potassium chloride.

In one embodiment the composition further comprises a starch. The starch may be a rice starch. Rice starch is preferred because of its relatively small particle size. It is particularly suitable for dry blends.

The disaccharide may be present in an amount from 10 to 90% by weight, in an amount of from 10 to 50% by weight, and in an amount of from 20 to 30% by weight. The disaccharide may be present in an amount of from 3 to 90% by weight, 3 to 50% by weight, 3 to 30% by weight and preferably from 5 to 16% by weight, most preferably about 10% by weight. Results have shown that at this preferably range the drip loss was minimised as a result of freezing. The disaccharide may be trehalose or lactose.

The non-starch polysaccharide may be present in an amount of from 3 to 80% by weight, in an amount of from 5 to 40% by weight, and in an amount of from 10 to 25% by weight. The non-starch polysaccharide may be present in an amount of from 2 to 80% by weight, 2 to 40% by weight, 2 to 25% by weight, preferably from 2 to 10% by weight, most preferably about 3% by weight. Results have shown that at this preferably range the drip loss was minimised as a result of freezing. The non-starch polysaccharide may be polydextrose or inulin or oligofructose.

In one embodiment the polyphosphate is present in an amount of from 5 to 70% by weight, in an amount of from 10 to 50% by weight, and in an amount of from 10 to 20% by weight. The polyphosphate may be present in an amount of from 20 to 30% by weight, most preferably about 25% by weight. The polyphosphate may be sodium tripolyphosphate. Results have shown that at this preferably range the drip loss was

minimised as a result of freezing and the active concentration of phosphate ions in the meat is achieved in this range.

The sodium chloride and/or potassium chloride may be present in an amount of from 10 to 40% by weight, in an amount of from 15 to 30% by weight. The sodium chloride may be present in an amount of from 10 to 50% by weight, preferably from 30 to 50% by weight, most preferably about 40% by weight.

In one embodiment the rice starch is present in an amount of from 5 to 60%, in an amount of from 10 to 35% by weight. The rice starch may be present in an amount of from 15 to 30% by weight, most preferably in an amount of about 22% by weight. The small granule size of rice starch enables it to penetrate into the meat more easily and deeper, in comparison to other starches. The starch binds with water forming a gel which is freeze-thaw stable.

In one aspect the invention provides a cryoprotective composition comprising trehalose in an amount of from 5 to 16% by weight, polydextrose in an amount of from 2 to 10% by weight, tripolyphosphate in an amount of from 20 to 30% by weight, sodium chloride in an amount of from 30 to 50% by weight and rice starch in an amount of from 15 to 30% by weight.

In another aspect the invention provides a cryoprotective composition comprising lactose in an amount of from 5 to 16% by weight, polydextrose in an amount of from 2 to 10% by weight, tripolyphosphate in an amount of from 20 to 30% by weight, sodium chloride in an amount of from 30 to 50% by weight and rice starch in an amount of from 15 to 30% by weight.

In a further aspect the invention provides a cryoprotective composition comprising trehalose and/or lactose in an amount of from 5 to 16% by weight, polydextrose and/or inulin and/or oligofructose in an amount of from 2 to 10% by weight, tripolyphosphate in

an amount of from 20 to 30% by weight and rice starch in an amount of from 15 to 30% by weight.

In one embodiment trehalose may be present in an amount from 10 to 90% by weight, in an amount of from 10 to 50% by weight, in an amount of from 20 to 30% by weight.

In one embodiment the polydextrose is present in an amount of from 3 to 80% by weight, an amount of from 5 to 40% by weight, in an amount of from 10 to 25% by weight.

In one embodiment the polyphosphate is present in an amount of from 5 to 70% by weight, in an amount of from 10 to 50% by weight, in an amount of from 10 to 20% by weight.

In one embodiment the sodium chloride and/or potassium chloride may be present in an amount of from 10 to 40% by weight, in an amount of from 15 to 30% by weight.

In one embodiment the rice starch is present in an amount of from 5 to 60%, in an amount of from 10 to 35% by weight.

In one embodiment the composition comprises a dry blend, typically a dry powder blend. This greatly facilitates preparation, transport and use of the composition. This will allow manufacturers prepare the cryoprotective brine without difficulty.

The invention also provides a liquid cryoprotective composition made up using the dry blend composition of the invention fish and meat, such as whole muscle, for example of white meat (such as poultry), pork, or red meat (such as beef) may be cryoprotected by injecting into the meat the liquid cryoprotective composition at a level of 2 to 15%

We expect that the composition may also be useful for cryoprotection of comminuted products such as patties, mince, sausages and the like at a level of 0.1 to 5% depending on the product type.

We have found that the combination of ingredients of the invention gives good cryoprotective effects. We have found that a good cryoprotective effect can be achieved with a combination of a disaccharide, especially trehalose or lactose, a polysaccharide, especially polydextrose or inulin, and a source of phosphate ions, especially polyphosphate. The ingredients have a synergistic effect as follows:

Without wishing to be bound by theory, we believe that trehalose forms a glass during freezing leading to increased stability of the preserved protein. We also believe that there is an interaction between the polysaccharide and polar groups in the proteins, thus preventing any conformational or structural changes during freezing. In addition, we believe that the polydextrose also forms a glass during freezing leading to increased stability of the preserved protein. As the glass deteriorates over time, we believe that the rice starch further stabilises the system thereby reducing the drip loss.

The nomenclature of phosphates depends on their chain length: orthophosphate have one phosphate group, diphosphates or pyrophosphates have two phosphate groups while polyphosphates have 3 or more phosphate groups. The diphosphate is the 'active form',in terms of the diphosphate induced dissociation of actomyosin allowing myosin solubilise easier. The longer chain forms take longer to convert to the diphosphate form and become active.

Phosphates may affect the water-holding capacity (WHC) of post-rigor muscle by increasing the pH of the muscle, which increases the net negative charges in the muscle. The negative charges increase the electrostatic repulsion between fibers and ultimately increase the hydration of the muscle. The synergistic effect between salt and alkaline phosphates improves yield and maximises myofibrillar protein solubilisation. Phosphate

anions also act as polyelectroytes to increase ionic strength. This addition of electrolytes will cause an increase in WHC by direct binding of water to the phosphate anions and by the repulsion of protein groups due to the increase in and predominance of negative charges on the protein groups. This repulsing effect opens up protein structure, an increase the number of binding sites available for water which allows for more water to be contained in meat. Furthermore, phosphates allow for the swelling of myofibrils to increase the extractability of protein. Pyrophosphate reduces very substantially the sodium chloride concentration required for maximum swelling and the presence of the pyrophosphate completely extracts the A-band in the myofibril.

We believe that polyphosphate through the action of phosphate anions increases ionic strength. This addition of electrolytes causes a repulsion of protein groups due to the increase in and predominance of negative charges on the protein groups. This repulsing effect opens up protein structures and increases the number of binding sites available to trehalose. In this invention we generally use sodium tripolyphosphate as the phosphate anion and pyrophosphate source.

Thus, this particular combination of ingredients complements one another by opening up the structure of the protein, thereby allowing the disaccharide and non-starch polysaccharide to interact with the protein and form a glass during freezing. This action appears to prevent any conformational and structural change of the proteins thus protecting them during the freezing process.

Preferably, the composition also includes a source of chloride ions such as NaCl which acts synergistically with the phosphate ions. The salt has a major effect on ionic strength. More specifically, the chloride ion serves a valuable role in causing electrostatic repulsion of the muscle proteins which opens up their structure.

The cryoprotective composition of the invention can be used to protect a wide variety of muscle proteins during long term frozen storage. The invention also provides a

cryoprotective method comprising the steps of injecting whole muscle meats, at low levels to incorporate the muscle with appropriate amount of cryoprotective ingredients in order to retard the denaturation of the muscle protein.

The cryoprotection composition will provide the food industry with a solution to protect muscle foods during extended period of frozen storage and will improve the quality of their products.

While the invention is described in relation to meat muscle cryoprotection it will be appreciated that the cryoprotective composition could be used in a wide range of other applications such as fish muscle and products, other proteins, plant tissue, enzymes, pharmaceutical and other biological tissues.

The cryoprotective composition of the invention is generally in the form of a dry blend. However, the blend can be re-constituted with water to form a liquid composition which may have a concentration of from 5% to 40% w/v. This can be injected into meat for preservation. In the case of preservation of biological materials more generally the composition may be added to an aqueous composition containing the biological material to be protected. The preservation system can then be preserved by any suitable technique such as drying (for example, spray drying, freeze drying or vacuum drying) or freezing.

Detailed Description

The invention will be more clearly understood from the following description thereof given by way of example only with reference to the accompanying figures, in which :-

Fig. 1 is a bar chart presenting the results of a cryoprotection trial for a cryoprotective composition of the invention against two controls;

Fig. 2 is a bar chart presenting the results of a cryoprotection trial for three cryoprotective compositions against a control and a comparative;

Fig. 3 is a bar chart presenting the results of a cryoprotection trial for nine cryoprotective compositions against a control;

Fig. 4 is a bar chart presenting the results of a cryoprotection trial for three optimised cryoprotective compositions against a control; and

Fig. 5 is a bar chart presenting the results of a cryoprotective trial in poultry meat of three cryoprotective compositions against a control.

The term non-starch polysaccharide refers to polysaccharides with a degree of polymerisation of 150 or less. They may be naturally occurring or synthetic and/or chemically modified. Also included are analogs thereof.

Polydextrose is a particularly preferred polysaccharide as we have found that it significantly enhances the cryoprotective properties of the composition. A detailed description of polydextrose is given for example in US2004/0213802A, the contents of which are herein incorporated by reference.

lnulin is also a preferred polysaccharide as we have found that it also significantly enhances the cryoprotective properties of the composition. Inulins are polysaccharides belonging to the polyfructan group. The fructose units in this mixture of linear fructose polymers and oligomers are each linked by β(2-l) bonds. The chain lengths of these fructans generally range from 2 to 60 units, with an average degree of polymerisation of about 10.

Oligofructose is also a preferred polysaccharide as we have found that it also enhances the cryoprotective properties of the composition. Oligofructose is a sub-group of inulin, consisting of fructose polymers with a degree of polymerisation of less than 10. Oligofructose may be referred to as an oligopolysaccharide.

The term disaccharide refers to carbohydrates that are made up of two monosaccharides. They may be naturally occurring or synthetic and/or chemically modified. Also included are analogs thereof. The most preferred disaccharides are trehalose (also referred to as mykose) which is a non-reducing sugar with known cryoprotective properties. We have also found that lactose (a reducing sugar) may be used as cryoprotective agent in the composition of the invention. Because of its non-reducing properties trehalose may be preferred for applications where any discoloration would be undesirable. One such application would be for cryoprotection of white meat such as poultry meat or fish. It is anticipated that other reducing disaccharides such as maltose, maltotriose, lactulose and sucrose may also be useful. Of these sucrose would not be preferred in applications where sweetness was not desirable.

Example 1

Pork topsides were injected to approximately 7% of their green weight with a cryoprotective brine solution, containing the various blends, using a Dorit Model No. PSM-21-4.5 multi-needle brine injector. A trial was formulated so that with an approximate injection level of 7% the injected meat contained the following:

Cryoblend 1 Phosphate Blend (Control 2) S SaaIltt [[NNaaCCll]] 0 0..3355%% Phosphate 0.4%

STPP 0.25%

Rice Starch 0.50%

Polydextrose 0.30%

Trehalose 0.40%

The polydextrose, a highly branched polysaccharide, is available from Danisco Sweeteners under the following brand name Litesse®. This is a brand for a family of polydextrose which are prepared from dextrose, sorbitol and citric acid.

Trehalose is available from Cargill Health & Food Technologies under the brand name ASCEND™ as produced by the Hayashibara method.

Rice starch is available from Remy Industries under the brand name Remyline and is prepared from rice.

Sodium tripolyphosphate is available from Europhos (Prayon) under the brand name Carfosel and is prepared from phosphoric acid. This is hereinafter referred to as STPP.

Based on these concentrations above the cryoblend was formulated as follows:

Cryoblend 1

Salt 19.44%

STPP 13.89%

Rice Starch 27.78% Polydextrose 16.67%

Trehalose 22.22%

After injection the muscles were reweighed, vac-packed and then frozen immediately at - 30°C. Muscles were then thawed at 1 week, 1 month, 3 months and 6 months. Drip loss was calculated as the differential weight before and after freezing.

Trials involving freezing, thawing and re-freezing at -30 ⁰ C were also carried out using these blends. The results were similar to those obtained without re-freezing.

The first trial [Fig. 1] shows that the cryoblend reduces purges loss by 8% in comparison to the control and by 4% in comparison to the control phosphate blend after 6 months frozen storage. The results show that the cyroblend effectively inhibits the protein denaturation of the muscles as a result of freezing.

Example 2

In a second trial (Figure 2) we varied the composition of the cryoblend so the meat had the following approximate concentrations:

This resulted in the following formulations:

All ingredients where blended by hand and packed. The blends where then added to the appropriate amounts of water as follows:

After injection the muscles were reweighed, vac-packed and then frozen immediately at - 30°C. Muscles where then thawed at 1 month, 3 months and 6 months. Drip loss was calculated as the differential weight before and after freezing.

Trials involving freezing, thawing and re-freezing at -30°C were also carried out using these blends. The results were similar to those obtained without re-freezing.

Results from the second trial [Fig. 2] are after 6 months frozen storage. The cryoblends show a protective effect by reducing the drip loss by 2.8-5.2%Cryoblend 1 has the same formulation as the cryoblend in the initial trial with Cryoblend 2 having a reduced rice starch, trehalose and polydextrose content. The results show that when rice starch is excluded (Cryoblend 3) the cryoprotective effect of the blend does not deteriorate significantly. However when both rice starch and phosphate is excluded (Comparative - cryoblend 4) the blend has no cryoprotective effect with a purge loss of 12.6%. When looking at both trials it can be seen that neither phosphates alone (Control 2) nor a blend of trehalose/polydextrose (Cyroblend 4 - comparative) has sufficient cryoprotective properties.

A blend of salt/phosphate/rice starch/trehalose/polydextrose has a cryoprotective effect on frozen pork muscles by reducing purge loss by 4-8%. A blend comprising phosphate combined with trehalose and polydextrose provides very effective cryoprotection.

Example 3

Results from a third trial are after 9 months frozen storage are illustrated in Fig 3. The methodology used was the same as in Examples 1 and 2. As with previous trials the cryoblends show a positive effect by reducing the drip loss by 3-5%. Cryoblend 1 has the same formulation as the cryoblend in the initial trial. The other cryoblends are similar except that other ingredients have been used instead of salt, STPP, rice starch, polydextrose or trehalose.

Cryoblend 1 19.44% NaCl 13.89% STPP

27.78% Rice Starch 16.67% Polydextrose 22.22% Trehalose

Crvoblend 5

19.44% NaCl

13.89% Disodium Monophosphate

27.78% Rice Starch

16.67% Polydextrose 22.22% Trehalose

Disodium Monophosphate is available from Europhos (Prayon). The monophosphate replaced STPP in the original formula. The results (Fig 3) show a slight improvement in drip loss. This may be due to the increased buffering effect of the monophosphate. However, monophosphates are not widely used in meat products (Troutt and Schmidt,

1983) due to the fact that pyrophosphate is responsible for the dissociation of actomyosin thereby improving the myosin solubility at salt levels commonly used in meat products.

Crvoblend 6 19.44% NaCl 13.89% STPP 27.78% Rice Starch 16.67% Polydextrose Ultra 22.22% Trehalose

Polydextrose Ultra - Litesse Ultra is available from Danisco. It is a sorbitol terminated randomly bonded polymer of D-glucose with some bound sorbitol and a suitable acid. The polydextrose ultra is a further refined polydextrose and replace the polydextrose (Litesse II) in the original cryoblend. It improved the drip loss compared to the original. This may be due to its slightly different functional properties e.g slightly higher pH and different molecular structure.

Crvoblend 7 19.44% NaCl

13.89% STPP

27.78% Rice Starch

16.67% Inulin

22.22% Trehalose

Inulin is available under the brand Raftiline from Orafti and replaced polydextrose, it showed an improvement in drip loss (4.3 v 5.3%).

Cryoblend 8 19.4% NaCl 13.8% STPP 27.78% Rice Starch 16.67% Oligofructosaccharide 22.22% Trehalose

Oligofructose is available under the brand Raftilose from Orafti and replaced polydextrose, it showed a slight increase in drip loss (5.7 v 5.3%).

Crvoblend 9

19.4% NaCl

13.8% STPP

27.78% Potato Starch 16.67% Polydextrose

22.22% Trehalose

Potato Starch is available from under the brand Farina from Avebe and replace the rice starch and showed a similar drip loss to the original.

Crvoblend 10

19.44% NaCl

13.89% KTPP

27.78% Rice Starch 16.67% Polydextrose

22.22% Trehalose

KTPP is available from Prayon and replaced STPP and showed a slight increase in drip loss (5.5 v 5.3%).

Cryoblend 11

19.44% Potassium Chloride 13.89% STPP 27.78% Rice Starch 16.67% Polydextrose 22.22% Trehalose

Potassium chloride replace NaCl and showed a slight improvement in drip loss, however the use of KCl is limited due to its metallic aftertaste.

Cryoblend 12 19.44% NaCl 13.89% STPP 27.78% Rice Starch 16.67% Polydextrose 22.22% Lactose

Lactose is available from Dairygold Food Products and most other milk ingredient suppliers and replaced trehalose and showed an improvement in drip loss (4.5 v 5.3%).

The results from this trial show that inulin had a positive impact (4.3 vs. 5.3%) when it replaced polydextrose while a different form of polydextrose gave a similar result. Likewise, lactose had a positive impact when it replaced trehalose (4.5 vs. 5.3). The results show that these cryoblends have a cryoprotective effect in frozen pork muscles. A blend comprising of salt and phosphate combined with trehalose or lactose, polydextrose or inulin provides very effective cryoprotection.

Example 4

A total of 14 blends with various formulations similar to cryoblend 1 were analysed using regression modelling techniques:

The results indicate that the optimum formulation is likely to be as follows with the specific ingredients indicated in % by weight:

Trehalose: 5 to 16% (preferably approximately 10%) Polydextrose: 2 to 10% (preferably approximately 3%) Sodium tripolyphosphate: 20 to 30% (preferably approximately 25%) Sodium chloride: 30 to 50% (preferably approximately 40%) Rice starch: 15 to 30% (preferably approximately 22%)

A fourth trial (Blends Cryoblends 13-15) involved looking at various combinations in these ranges. The results (Fig. 4) show that the formulations reduced the drip loss further

after freezing (1.6-1.9 versus 8.8%). The results also show that when rice starch is removed and with an increased concentration of salt and phosphate the drip loss remains low

Cryoblend 13 Cryoblend 14 Cryoblend 15

Salt 40.00% 38.76% 51.00%

STPP 25.00% 25.00% 32.00%

Rice Starch 22.00% 23.00% 0.00%

Polydextrose 3.00% 8.24% 12.00%

Trehalose 10.00% 5.00% 5.00%

100 100 100

Example 5

A fifth trial was carried out on poultry meat using cryoblend 1 , a blend containing inulin (replacing the polydextrose), and a blend with a low phosphate content as follows. The methodology used was the same as in Example 1 and 2.:

Cryoblend 1 Cryoblend 7 Cryoblend 16

Salt 19.44% 19.44% 25.00%

STPP 13.89% 13.89% 3.06%

Rice Starch 27.78% 27.78% 16.39%

Polydextrose 16.67% - 22.22%

Trehalose 22.22% 22.22% 33.33%

Inulin - 16.67% -

100 100 100

Results are illustrated in Fig. 5 and show that as with previous trials the blends show a increased level of cryoprotection, in terms of less drip loss after freezing compared to the control.

The invention is not limited to the embodiments hereinbefore described which may be varied in detail.

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