Preservative effect of nisin in food

Nisin mainly has two forms in the natural state, namely NisinA and NisinZ, which are refined by fermentation and culture of nisin, and the solubility and antibacterial ability of the latter are greater than those of the former.

In Meat Products

Nisin can effectively inhibit the gram-positive bacteria that cause food spoilage, such as Listeria, Staphylococcus aureus, Clostridium botulinum and various spoilage microorganisms. times the shelf life. Adding 5-15g/100kg of nisin, combined with a small amount of other preservatives, can make the shelf life of low-temperature meat products at room temperature for more than three months.

In Dairy Products

Add 0.05g/kg nisin to yogurt and fruit milk with a pH value of about 4. After sterilization at 90°C and 20min, the shelf life of the product is extended from 6d at room temperature to more than one month; after ultra-high temperature sterilization, no Bacteria-filled milk, adding 0.05g/kg nisin product spoilage rate from 0.04% to 0; adding 0.08-0.1g/kg nisin in canned sugar-free condensed milk can inhibit the formation of heat-resistant spores. For growth, reduce the heat treatment time by 10min; add 0.08g/kg nisin, and heat treatment at 121°C for 3 minutes (F0=3) to make low-fat milk, unsalted butter, fat-free milk, and flavored milk. At 40°C, it can still be stored for up to six weeks; in cheese, adding 0.05g/kg-0.1g/kg nisin can solve the problem of heat-resistant gram-positive bacteria spores (such as gram-positive bacteria) during cheese processing. Corruption caused by Clostridium botulinum and other anaerobic Clostridium, Lactobacillus bulgaricus, etc.).

In Canned Food

Canned food is often contaminated with some extremely heat-resistant bacterial spores, such as the spores of Bacillus stearothermophilus and Clostridium pyrolyticum. Once the conditions are suitable, they will grow, causing gas production, acid production and spoilage. The addition of 0.1g/kg of nisin to canned food can keep canned food in hot conditions for 2 years. And can reduce heat treatment intensity by 1/2, save energy, keep canned food good nutritional value, appearance, flavor, color, maintain product quality, prolong food shelf life, and its effect is better than potassium sorbate.

In Cooked Aquatic Products

Seafood products such as fish and fresh shrimp are loved by people for their delicious taste and high nutritional value, and they are often eaten cold. Because they are easily spoiled and deteriorated, they are easily contaminated by Listeria and E-botulinum. Controlling the number of bacteria in the finished product is very important. very important. Adding 0.1-0.15g/kg of nisin can inhibit the growth and reproduction of spoilage bacteria and prolong the freshness and shelf life of the product. Raw shrimp meat is the main material, and the processed shrimp minced meat generally only has a shelf life of 2 days. After adding nisin, the shelf life can reach 60 to 70 days.

In Fruit Drinks

The cause of rancidity in fruit juices and juice beverages comes from Geobacillus acidophilus, an acid- and heat-resistant spore-forming rod-shaped bacterium. It is suitable for growth and reproduction in the environment of 25°C-60°C and pH 2.5-6.0. Geobacillus acidophilus exists in the process of beverage production and water use, and it is easily brought into fruit juice and juice beverage products. Corruption of fruit juice products. Adding 0.05-0.1g/kg nisin, pasteurization can prevent the growth and reproduction of surviving Geobacillus acidophilus spores, prevent product spoilage, and meet the quality assurance requirements.

In liquid Eggs and Egg Products

The addition of 0.05g/kg—0.1g/kg nisin to egg products can effectively inhibit the heat-resistant spores that cause product spoilage, and extend the shelf life of egg products with an original shelf life of 7 days to more than one month.

In Condiments

0.05g/kg—0.2g/kg of nisin is added to salad dressings, etc., which can effectively inhibit the growth of lactic acid bacteria and spores, reduce the spoilage of low-fat and low-salt products, and prolong the shelf life by more than 3 times.