Application of nisin in pickles

Food Business Network News Pickles are a general term for various vegetable products made from fresh vegetables as the main raw material and made by different pickling techniques. Because of its fermentation or high salt, it was originally one of the ways people used to preserve vegetables. However, in recent years, with the continuous improvement of people's diet structure, pickles have developed toward low salt, acid and sweet. On the one hand, the raw material of the pickled vegetables is very high. On the other hand, the salt concentration is very suitable for the proliferation of microorganisms. Therefore, the pickled products are prone to spoilage and deterioration at room temperature, and it is difficult to preserve.

In order to meet the requirements of commercial sterility, the traditional practice is to sterilize the pickled products for a long time under high temperature and high pressure, but at the same time killing the microorganisms, it also causes great damage to the quality of the pickles, which leads to The product's brittleness is reduced, the color is deteriorated, the aroma and taste are not good, and the nutrients such as vitamins are also destroyed and lost, eventually losing the commercial value of the product. Therefore, many companies have abandoned this sterilization method and chose a milder bacteriostatic treatment process such as boiling water bath, pasteurization, steam cooking and the like. However, this type of process can only kill the vegetatives of microorganisms, but not the spores with strong heat resistance. Therefore, if the spoilage bacteria and their spores are germinated and propagated again under suitable conditions during storage, there is a risk of spoilage of the product during the shelf life.

Therefore, in order to extend the shelf life of pickles, it is necessary to add a preservative to the product to inhibit the growth of spoilage bacteria. Because chemical preservatives such as benzoic acid and sorbic acid are cheap and have low anti-corrosion costs, in order to make the pickled products have a long shelf life, some manufacturers over-add, resulting in excessive levels of preservatives in the pickled products. In recent years, the state has strengthened food safety supervision, and traditional chemical preservatives have been unable to meet the needs of the market. The market is in urgent need of a green, healthy and efficient preservative.

As an ideal natural food preservative, nisin has been recognized by more than 70 countries in the world and is widely used in various foods. Nisin can effectively inhibit many Gram-positive bacteria that cause food spoilage, such as Lactobacillus, Leuconostoc, Pediococcus, Staphylococcus, Listeria, etc., especially for spore-forming bacteria such as Bacillus, fusiform Bacillus has a strong inhibitory effect. The spores that can not be killed after pasteurization, steaming, etc., and the Gram-positive bacteria that are not easy to kill, nisin can play a very good inhibitory effect. Compared to traditional chemical preservatives, nisin has a very significant advantage.

First, nisin is a green safe biopreservative. The British company Aplin collected 251 milk samples from 9 countries and found that 109 samples contain nisin-producing Streptococcus mutans, indicating that this substance has long been naturally found in people's daily consumption of milk. In addition, bacteriological studies have demonstrated that nisin is completely non-toxic. Studies have shown that nisin is particularly sensitive to proteolytic enzymes (such as trypsin, etc.), so it can be quickly hydrolyzed into amino acids by proteolytic enzymes in the gastrointestinal tract after consumption in the digestive tract. After 10 minutes of ingestion of nisin, the activity of nisin is not detected in saliva, so it does not remain in the body, nor does it change the normal intestinal flora. It is a safe preservative. . There are many countries in the world such as the United Kingdom, France, and Australia that do not impose any restrictions on the amount of nisin added to food. China’s former Ministry of Health clearly stated in the documents approved for implementation: “It is scientifically safe to think that nisin is safe as a food preservative.”

Second, the use of a combination of nisin preservatives can significantly reduce the amount of chemical preservatives used. The researchers isolated the microorganisms from the pickled vegetables purchased in the market, and conducted the minimum inhibitory concentration experiment. The traditional sodium benzoate or potassium sorbate was used alone or in combination, even if the dosage reached the national limit of 1.0g/kg. It is also difficult to completely inhibit the growth of pickled microorganisms; while nisin and its complexation only need 0.4g / kg potassium sorbate + 0.2g / kg nisin + 0.15g / kg EDTA + 0.03g / kg Otamycin can achieve the desired bacteriostatic effect.

Code Safe

Code Safe,Smart Safe,Home Security Secret Book,Money Strongbox Metal Safes

Ningbo Reliance Security Technology CO.,Ltd , https://www.reliancesafes.com

Posted on