Glutamine transaminase, known as the 21st century binder, is a bio-enzyme preparation isolated and purified by microbial fermentation. It can catalyze covalent cross-linking of proteins or molecules and improve the structure and function of proteins. If it is added to the meatballs, it can replace the composite phosphate, which can increase the elasticity and increase the brittleness. So in the processing of meat products, the use of glutamine transaminase needs to pay attention to those problems?

1, determine the role of the object

The target of glutamine transaminase is protein. The common substrates of common glutamine transaminase are casein and sodium salt in milk, gelatin and myosin in meat, 11s globulin in soybean protein and 7s ball. protein. Catalytic is the reaction of the "reactive" glutamine residue, so the protein content and the "reactive" glutamine residue content have a great influence on the effect of glutamine transaminase. The reaction also requires the presence of a lysine residue, otherwise the role of glutamine transaminase can only be to change the solubility of the protein and its associated properties.

The role of glutamine transaminase is protein, otherwise the role of glutamine transaminase can only change the solubility of proteins and their related properties.

2, the optimum reaction temperature

The glutamine transaminase is stable at 0 °C - 40 °C, and after 50 °C, the enzyme activity gradually decreases with increasing temperature, and is inactivated below 10 °C and above 75 °C. Under the premise of ensuring the quality of the product, it directly affects the amount of TG enzyme added and the length of time required for the catalytic reaction. For example, for low-oil and easily deteriorated products such as fish, meat and dairy products, the selected reaction temperature is low ( 1 ~ 10 ° C), and the corresponding reaction time is longer (2 ~ 12 hours or more), such as the reaction temperature (40 ° C -50 ° C), correspondingly shorten the reaction time (15-20 minutes).

3, the optimum range of PH value

Glutamine transaminase has good pH stability and is stable over a wide range of pH values (5-8). Therefore, the environment should be between pH 6 and 7 and preferably not more than pH 5 to 8. . For example, adding salt and other seasonings to foods can be added after mashing to avoid the effect of high concentration salts (>1%) on glutamine transaminase.

4, the best amount of addition

The addition amount is added from 0.3% to 0.5% of the total amount of the material. Due to the difference in the production process, environment and food production process, and the characteristics of the product, it should be based on the percentage of raw materials and auxiliary materials used in the food processing process, and glutamine. The optimum addition amount of the temperature and time processing technology of the transaminase action, and even the processing cost and the cost performance of the product. When the optimum amount of addition cannot be determined, it can be obtained by a small test while avoiding the loss of materials.

5, according to different products, choose whether you need to kill enzymes

Glutamine transaminase is stable at 0 °C-40 °C, and it is determined according to the actual product, such as yogurt, the production process is (fresh milk → blending → homogenization → sterilization → cooling to 40) - 50 ° C → add glutamine transaminase → inoculation → fermentation → refrigeration), due to the characteristics of yogurt products, do not need to destroy the enzyme. However, the kanafu tofu, which is also reacted at a low temperature overnight, may affect the quality of the product if it is not inactivated by the enzyme, and the glutamine transaminase may be inactivated by cooking (inactivation at 80 ° C for 1 minute).

Glutamine transaminase is an SH enzyme with a cysteine active center, and the oxidation of the SH-group deactivates the enzyme, so it is vacuum packed.

6, keep the enzyme activity to create an anaerobic environment

Glutamine transaminase products are usually packaged in vacuum, because glutamine transaminase is an SH enzyme with a cysteine active center, and oxidation of the SH-group can inactivate the enzyme, so it is processed. The application must maintain the activity of the enzyme as much as possible, so that the effect of glutamine transaminase is more ideal. The vacuum environment can be maintained before the enzyme is added to the end of the enzyme reaction, such as vacuum agitation, filling and shaping, followed by adding a sulfur-containing SH-containing substance such as glutathione (glutarine-containing yeast) to the food. Extract) and cysteine. Glucose oxidase (glucose oxidase can remove oxygen from food and containers to effectively prevent food deterioration) and its substrate glucose, blocking oxygen and react with aminoamide transaminase, is added to foods.

Compared with chemical preparations, the cost of glutamine transaminase is relatively high, but it has the safety advantage unmatched by chemical preparations. With the large application of glutamine transaminase and continuous research investment, it is believed that glutamine transaminase is used in the meat industry. Development will have a greater role to play.