Views: 125 Author: Site Editor Publish Time: 2022-10-25 Origin: Site
Dehydroacetic acid and its sodium salt are white or light yellow crystalline powder, stable to light and heat, degraded to acetic acid in aqueous solution, non-toxic to human body. It is a broad-spectrum preservative and has a strong inhibitory effect on bacteria, moulds and yeasts in food. It is widely used in the preservation of meat, fish, vegetables, fruits, beverages and pastries.
Products include methyl, ethyl, propyl and butyl parabens. Among them, butyl paraben has the best preservative effect. China mainly uses ethyl and propyl paraben esters. Butyl paraben is the most used in Japan. The preservative mechanism of nipagin ester is that it destroys the cell membrane of microorganisms, denatures the proteins in the cells and inhibits the activity of the respiratory enzyme system of the cells. The antibacterial active ingredient of nipagin ester is mainly in the molecular state, as the hydroxyl group within the molecule has been esterified and is no longer ionised, 60% of the molecule is still present at a pH of 8. Therefore, nipagin ester is effective in the pH range of 4 to 8. It does not change with PH, is stable and less toxic than benzoic acid. It is a broad-spectrum preservative. As nipagin esters are insoluble in water, they are first dissolved in ethanol when used. For better preservative performance, it is best to mix two or more of these esters. Ethyl paraben is generally used in fruit beverages and propyl paraben is generally used in fruit beverages.
A preservative commonly used in pickles, safe, non-toxic, with good preservative effect, the final decomposition products in the human body are water and carbon dioxide. It has a good preservative effect. In sauces, 0.2% sodium diacetate and 0.1% potassium sorbate are used in sauces, which has good preservation effect.
White crystalline granules or powder, odourless or with slight propionic acid odour, stable to light and heat, easily soluble in water. Propionic acid is the product of oxidation of amino acids and fatty acids in the human body, so calcium propionate is a very good safety preservative. It has an inhibitory effect on moulds, has a small inhibitory effect on bacteria, has no effect on yeast, and is commonly used in the fermentation of pasta products and cheese products to prevent moulds, etc.
The product is colourless or slightly yellow transparent liquid, odourless, slightly salty and bitter, miscible in water, ethanol and glycerin. The general concentration of 60%-80%, 60% of the concentration of the maximum use limit of 30g/KG. sodium lactate is a new type of preservative and preservation agent, mainly used in meat and poultry products, has a strong inhibitory effect on meat food bacteria. Such as E. coli, Clostridium botulinum, Listeria monocytogenes, etc. Through the inhibition of food pathogenic bacteria, thus enhancing the safety of food. Enhances and improves the flavour of meat and extends shelf life. Sodium lactate has good dispersion in raw meat and good adsorption of water, thus effectively preventing dehydration of raw meat and achieving freshness and moisture retention. It is mainly applied to roast meat, ham, sausages, chicken, duck and poultry products and sauce and brine products. Reference formula for preserving freshness in meat products: sodium lactate: 2%, sodium dehydroacetate 0.2%.
The production of biological preservatives in China was started by streptococcus lactis, which has a history of ten years. Some progress has been made in the research, production and application of biological preservatives. gb2760 stipulates that streptococcus lactis and natamycin can be used, and the development of polylysine (now offered by four companies) has been started since 2006. work on applying for polylysine to enter gb2760 is underway and it is believed that it will be put on the market soon. There are also products marketed that claim to be biological preservatives but are in fact compounded formulations.