There are many types of preservatives, their bacteriostatic mechanism and bacteriostatic spectrum are different, a single food preservative can usually only play a killing or inhibiting effect on a specific spoiled bacteria, while there is no inhibitory effect or weak effect on other bacteria, and it is also easy to make microorganisms adaptable. Based on the fence technology, the synergistic effect of different types of preservatives can not only enhance the bacteriostatic effect, but also reduce the amount of single preservatives used. This paper lists the application of four compound preservatives in food production.
<h1 class="pgc-h-arrow-right" data-track="2" >01, natamycin, and streptococcin lactate were studied[1</h1>].
The compounding of natamycin and streptococcin lactate can simultaneously inhibit the growth of fungi and bacteria, prolong the shelf life of food, and has high research value in the food industry.
Natamycin, referred to as Natamycin, is mainly a polyene macrolide antibacterial agent obtained by the fermentation of Streptomyces natal and Streptomyces brownosa, which is a odorless and odorless crystalline powder. Natamycin can effectively inhibit and kill yeast and mold, inhibit food spoilage and mycotoxins to cause damage to the human body.
Physicochemical properties of natamycin
Natamycin is an amphoteric substance with 1 acidic group and 1 alkaline group in the molecule, which is almost insoluble in water and most organic solvents, and is more soluble in dilute acid dilute alkali solutions such as glacial acetic acid and dimethyl sulfoxide. Due to the cyclic molecular structure, the stability of natamycin is affected by factors such as light, temperature, heavy metals, ph and so on. The PH should be kept within the range of 4 to 7 when using, while avoiding high temperatures and light.
Bacteriostatic mechanism of natamycin
Natamycin is a specific and highly effective antifungal agent, which has a good inhibition effect on almost all yeasts and molds. The bacteriostatic mechanism of natamycin is that it combines with ergosterol on the cell membrane to form a complex that changes the structure and permeability of the cell membrane, causing intracellular electrolytes, amino acids and other substances to leak, further causing cell death. Li Dong et al. have shown that the minimum inhibitory concentration of natamycin on Aspergillus is 0.63mg/kg, the minimum inhibitory concentration of Aspergillus niger is 1.80mg/kg, and the minimum inhibitory concentration of Penicillium is 1.10mg/kg. Zhang Xuan and other studies have shown that natamycin has a significant inhibitory ability on fungi, and the minimum inhibitory concentration is roughly 1mg/L.
Streptococcus lactate, referred to as Nisin, is a peptide substance with bactericidal effect produced by Streptococcus lactate in the metabolic process, which is composed of 34 amino acid residues, which is a natural preservative with high efficiency and non-toxic side effects. The antimicrobial spectrum of streptococcin lactate is narrow and can only effectively inhibit food spoilage caused by bacteria.
The image was posted by account_deleted on Pixabay
Physicochemical properties of streptococcin lactate
Streptococcin lactate is very stable under acidic conditions, especially when the PH < 2.0 can tolerate sterilization at 121 °C without inactivation; when the PH is neutral and alkaline, the vitality of streptococcin lactate is basically lost after sterilization. The solubility of PH and streptococcin lactate is also closely related, and its solubility increases as PH decreases.
Bacteriostatic mechanism of streptococcin lactate
Streptococcin lactate has a good bacteriostatic effect on most gram-positive bacteria, especially on Staphylococcus aureus and Bacillus. It can act on the bacterial cell membrane, form a pore-like structure, break the balance inside and outside the cell, and lead to cell death; it can also inhibit the synthesis of peptidoglycans, hindering the synthesis of the cell wall, thereby inhibiting cell growth. Jiang Ali et al. have shown that when PH is acidic, the concentration of streptococcin lactate is higher than 10 μg/mL, which has a certain bacteriostatic effect on Listeria monostizois.
Application of compound preservatives in the food industry
Yi Jianhua et al. found that streptococcin lactate and natamycin compound preservatives have the best bacteriostatic ability for low-salt pickles. The combination preservatives of streptococcin lactate and natamycin have little effect on pickle acidity and organolepticity within 3 months, and the bacteriostatic effect is very good.
Gu Jiaying and other studies found that adding 15g/kg of lactic acid streptococcusin and 100mg/kg of natamycin compound solution to the egg yolk filling can achieve the purpose of internal antiseptic, and spraying the skin of the egg yolk mooncake with 300mg/kg of natamycin solution can achieve the purpose of external antiseptic.
Li Qingxiu et al. applied the combination of streptococcus lactate and natamycin to chicken meat, which well inhibited the growth of putrefactive microorganisms in chicken meat and had no impact on the taste of chicken meat.
Ding Peifeng et al. studied the application of natamycin, streptococcus lactate and tea polyphenols in soy sauce preservatives through experiments, and found that a single preservative cannot play a good bacteriostatic effect, while the 3 kinds of preservatives are compounded proportionally, which can make the shelf life of soy sauce reach 1 year.
Zhang Yuxin's research showed that when the ratio of streptococcin lactate to natamycin is 0.02:0.0065, its bacteriostatic effect is comparable to potassium sorbate, which can effectively inhibit the growth of spoilage bacteria in convenient fabric packages.
<h1 class="pgc-h-arrow-right" data-track="21" >02, application of streptococcin lactate and chemical preservatives in steamed cakes</h1>
At present, the chemical preservatives commonly used in pastries have a good inhibitory effect on mold and yeast, while the inhibitory effect on bacteria is weak. The biological preservative streptococcus lactate is a polypeptide substance with antibacterial activity extracted from the fermentation products of Lactococcus lactis, which can inhibit the growth and reproduction of many gram-positive bacteria that cause food spoilage, especially the spores produced by Bacillus thermotrope and Clostridium botulinum have a strong inhibitory effect.
Image source: Qiantu network members
Zhang Panxian [2] et al. selected streptococcin lactate and commonly used chemical preservatives to inhibit and optimize the compounding of spoiled microorganisms in steamed cakes, and the conclusion showed that the compound preservatives (0.2g/kg streptococcus lactate + 0.25g/kg sodium dehydroacetate + 0.3g/kg sodium propionate) can significantly inhibit the growth of putrefactive microorganisms in steamed cakes, and the bacteriostatic effect is better than that of chemical preservatives (sodium dehydroacetate and sodium propionate), which can improve the quality of the product and extend the shelf life of the product. Compared with chemical preservatives (sodium dehydroacetate and sodium propionate), compound preservatives with streptococcal lactate not only enhance the ability to inhibit the spoiled microorganisms in the steamed cake, but also reduce the amount of chemical preservatives added and improve the safety of the product.
<h1 class="pgc-h-arrow-right" data-track="25" >03, application of compound preservatives in smoked sausages</h1>
Yao Yuan et al. found that high concentrations of sodium lactate can cause denaturation of pork actin and myosin heavy chains; The low concentration of sodium lactate has little effect on protein expression in pork. The bacteriostatic effect of the compound preservative based on sodium lactate is mainly through the effective penetration of bacteria and mold cell walls and interference with the interaction of enzymes, inhibiting the production of bacteria and mold, so as to achieve efficient bacteriostatic, anti-mildew, anti-corrosion and other purposes.
Zhang Lifeng [3] et al. took low-temperature smoked sausages as the research object in the experiment, and carried out preservation and antiseptic tests with single and compound preservatives respectively, and the conclusion showed that the bacteriostatic effect of each single and compound preservative was measured by the changes in volatile salt-based nitrogen (TVB-N) and the total number of colonies in the smoked sausage before and after treatment, and the antiseptic effect of the compound preservative was found to be better than that of the single preservative.
And the test showed that the compound sodium lactate (2.0% sodium lactate + 0.04% sodium diacetate solution + 0.006% streptococcin lactate) had the best bacteriostatic effect. The compound product can significantly extend the shelf life of the smoked sausage, and has the characteristics of good antiseptic effect, simple application, economy, safety and harmlessness, and has broad market prospects.
<h1 class="pgc-h-arrow-right" data-track="30" >04, effects of tea polyphenol compound bacteriostatic agents on the quality change of cold fresh pork storage period</h1>
Due to consumers' fear of chemical preservatives, scholars have turned their attention to cold fresh meat preservation materials to natural preservatives, which are favored by scholars for their broad spectrum, high efficiency and safety characteristics. So far, the natural preservatives commonly used in cold fresh meat are: tea polyphenols, lactic acid streptococcin, chitosan, natural spices, citric acid, lactic acid, lysozyme and so on.
In the early days of natural preservative research, many scholars have studied the bacteriostatic spectrum of a single natural preservative and its effect on the dominant spoilage bacteria in meat and meat products. However, with the limited effect of a single bacteriostatic agent on the quality of meat products, people have gradually changed the research direction from single factor to multi-factor synergy, and the use of bacteriostatic agents also tends to be used in combination with a variety of bacteriostatic agents to achieve a synergistic bacteriostatic effect.
Luo Jia [4] et al. used the cold fresh meat of domestic pig slaughtering enterprises as raw materials, and used the compound solutions of natural preservative tea polyphenols, streptococcus lactate and sodium lactate to study the effect of different concentration combinations on the freshness of cold fresh pork, and the results showed that in the one-factor test, the solutions of tea polyphenols, sodium lactate and streptococcin can significantly extend the shelf life of cold fresh meat.
From the results of orthogonal testing, it can be seen that the effects of three natural preservatives on the quality of cold fresh meat are, in order: tea polyphenols> sodium lactate> streptococcin lactate. The optimal ratio of tea polyphenols to sodium lactate and streptococcin lactate compound solution was finally determined: tea polyphenol 0.02%, sodium lactate 0.25%, streptococcin lactate 0.04%, which can extend the shelf life of cold fresh meat to 9 days.
With the improvement of people's material living standards, people's demand for food is increasing, which makes some food need to be stored and transported for a long time before it can be eaten, so it is inevitable to prevent food. Different types of preservatives can play a better inhibitory effect on different types of microorganisms, so as a production enterprise, it is necessary to fully understand the characteristics of preservatives and improve the antiseptic effect through the form of compounding.
bibliography:
Feng Linhui,Li Yingqiu. Application of natamycin and streptococcin lactate compound in food. Chinese Condiments. Volume 44, Issue 2, February 2019
Zhang Panxian,Ye Shengde,Zhou Bin. Application of compound preservatives in steamed cakes. Chinese food additives
Zhang Lifeng,Ning Haifeng,Liu Yudong,Zou Song. Application of compound preservatives in smoked sausages in the meat industry. Issue 9 of 2017, issue 437
[4] Luo Jia,Zhou Yi,Wang Liting,Cheng Lijia,Wang Juan. Effects of tea polyphenol complex bacteriostatic agents on the quality change of cold fresh pork during storage period. Light Industry Technology. Volume 37, Issue 3, 2021
Source: Food R & D and production Finishing, please indicate the source when reprinting.
Reminder: The article is for reference only, if there is any impropriety, welcome to leave a message to correct and communicate. Moreover, readers should not act on the content of the article without authorization in the absence of specific professional advice, and the operator of this official account is not responsible for the losses caused. If the article involves infringement or does not want to be published on my platform, please contact us.