Phosphates in meat products have the effect of maintaining the water holding capacity of the meat and enhancing the adhesion. Meat in the freezing, refrigeration, thawing and heating and other processing, will lose a certain amount of water, and make the meat hard, and because of the loss of water and the loss of some soluble proteins and other nutrients.

When adding phosphate in meat, it can improve the water holding capacity of meat, so that meat in the processing process can still maintain its moisture, so that the meat nutrients less loss, but also to preserve the tenderness of the meat.

At present, there are 18 kinds of phosphates approved for use in China, including sodium tripolyphosphate, sodium hexametaphosphate, sodium pyrophosphate, trisodium phosphate, disodium hydrogen phosphate, disodium dihydrogen phosphate, sodium acid pyrophosphate, disodium dihydrogen pyrophosphate and so on.

Adding these substances to food helps to diversify food varieties, improve their color, aroma, taste and shape, maintain the freshness and quality of food, and meet the needs of the processing process. They are very important quality improvers.

Application of phosphate in meat products

1, in the role of meat processing

(1) Increase the pH value of meat;
(2) Chelating metal ions in meat;
(3) Increase the ionic strength of meat;
(4) dissociate actinomyosin.

Therefore, the addition of phosphate improves the water retention and yield of the product. However, the ability of phosphates to improve water retention of meat and to improve meat quality conformation depends on the type of phosphate applied, the conditions under which the phosphate system is applied, and the amount of phosphate added.

2, in the application of improving muscle protein water retention gel

The order of factors affecting the water retention of chest muscle protein gel is: sodium pyrophosphate > sodium tripolyphosphate > sodium hexametaphosphate; the order of factors affecting the water retention of leg muscle protein gel is: sodium hexametaphosphate > sodium pyrophosphate > sodium tripolyphosphate.

The different effects of the two muscle types were mainly due to the different muscle types and the different mechanisms of phosphate action. The test showed that pyrophosphate had a significant effect on the water retention of breast meat, which was attributed to the fact that pyrophosphate increased the pH value, which increased the water retention of the gel through hydration, and at the same time dissociated myosin into myosin and actin, and the protein molecules combined with water to improve the water retention.

The effect of tripolyphosphate on the water retention of leg meat protein gel is not obvious, at this time the effect of gel water retention is the structure of the gel, the water retention of the gel is good that the formation of the gel network is more detailed, a large number of tiny pores uniformly distributed in the gel network, with the help of the capillary force, to keep some water.

In terms of heat-induced gel strength of muscle protein, phosphate, however, has a reducing effect on its gel strength. Foreign literature reported that sodium pyrophosphate makes myosin unstable and reduces the gel strength, and interacts with myofibrillar gels, and sodium tripolyphosphate also makes myosin unstable, and improves myofibrillar protein gelation at 0.3 mol/liter and 0.4 mol/liter of sodium chloride, but reduces the gelation ability at 0.6 mol/liter of sodium chloride.

Sodium hexametaphosphate had no effect on myosin denaturation, but it increased gel strength. The effects of phosphates on muscle proteins are mostly attributed to the changes in ionic strength and pH that they bring about.

3、Application in improving water retention and yield

Add phosphate in meat products can improve the texture of the product, improve the water retention and product yield, improve the quality of meat quality structure, so as to reduce the cost of the product without lowering the quality of the product under the premise of reducing the cost of the product.

The principle of phosphate to improve the water retention of meat products is:
Tripolyphosphate and pyrophosphate can change the potential of the protein charge to improve the ionic strength of the meat system, and make it deviate from the isoelectric point, so that the charges are mutually exclusive, between the proteins to produce a larger space, that is, the protein “puffing”, so that the meat organization can contain more water and thus improve the water retention;

Hexametaphosphate can chelate metal ions, reduce the combination of metal ions and water, so that the protein combined with more water to improve water retention. It has been proven that a mixture of multiple phosphates is more effective than a single one, so mixed phosphates are usually used to increase the effect.

The optimal ratio of compound phosphate is 2:2:1 (sodium tripolyphosphate: sodium pyrophosphate: sodium hexametaphosphate) in most meat products (e.g., pork ham, beef, minced fish), but the optimal amount of phosphate used varies a lot from product to product, with the optimal amount of ham being 0.4% but for fish, the optimal amount of phosphate used is 0.5%;

The water retention effect of complex phosphates on surimi products was better than that of single phosphates, while the products had better color, taste, smell and texture;

However, in chicken products, the optimal phosphate ratios for obtaining the maximum yield were 32.6% for sodium hexametaphosphate, 45.6% for sodium tripolyphosphate and 21.8% for sodium pyrophosphate.

The larger the amount of compound phosphate added, the higher the yield, that is, the greater the positive effect on the water retention of products, but the dosage of more than 0.4% for chicken, more than 0.5% for fish, the product yield tends to slow down the upward trend.

4, in improving the application of tenderness
Compound phosphate is alkaline, which can improve the pH value of meat and promote the tenderizing effect of calcium-activated enzyme on meat. At the same time, compound phosphate with more negative charge, a lower concentration of compound phosphate can significantly increase the ionic strength of the solution, and thus can chelate metal ions, such as magnesium, zinc, etc., so that the protein-COO-terminal exposure, enhance the meat electrostatic repulsion for the meat relaxation, increasing the tenderness of the meat.

As the tenderness of meat and connective tissue and myogenic fiber content, the more collagen cross-linking in the connective tissue, the worse the tenderness of meat. The addition of compound phosphate can increase the solubility of collagen and reduce the cross-linking of collagen in the connective tissue, improving the tenderness of meat.

Compound phosphate can also make the actinomyosin dissociation, lifting the muscle stiffness, so that the tenderness of the meat is improved. The ratio of compound phosphate used is: tripolyphosphate: pyrophosphate: hexametaphosphate – 2:2:1, and its addition of 0.5% when the tenderizing effect on beef and rabbit meat is optimal, it is advisable to use the method of injection marinade for 16 hours.

Safety of Phosphates

Phosphate is the active ingredient of human tissues, such as teeth, bones and enzymes, and plays an important and indispensable role in the metabolism of important nutrients, such as sugars, fats and proteins. Therefore, phosphate is often used as a food fortifier.

However, when dietary phosphate levels are excessive, they can reduce calcium absorption and lead to calcium loss from human skeletal tissue. If it lasts for a long time, it can also cause developmental delays and bone deformities. Therefore, phosphate must be added and used strictly within the scope of use specified by the state.

How to Use Compound Phosphates

A phosphate-degrading enzyme present in meat products breaks down phosphates and renders them useless. Therefore, in the meat production process should also pay special attention to choose the appropriate process to add, in order to avoid destroying the role of phosphate.

Generally in the meat production and processing, usually choose to use the best effect in the marinade after the rolling mix; there is also the use of solution marinade method. At the same time, taking into account the excessive addition of phosphate will also degrade the flavor and color of the product, and is not conducive to human health.

Therefore, the amount of compound phosphate is taken as 0.4% for chicken and 0.5% for fish. The amount of phosphate added to meat should be in accordance with the standards issued by the state.

Conclusion

Like other additives, quality improvers will be compounded into complex quality improvers according to a certain formula. These quality improvers are very convenient and effective.

In the United States, carrageenan, phosphate additives have been successfully used to produce low-fat, low-salt, low-calorie and high-protein poultry food with health effects. This additive is mainly used to maintain the moisture in the poultry meat, and make the product in the salt content than the original reduction of 50%, in addition to increasing the volume of cooked poultry meat products, maintain product flavor, improve the structure, improve the cutability and other characteristics. Phosphate-ascorbic acid complex improver can be used to inhibit the oxidation of meat lipids.