Application of propolis as the hottest preservativ

Application of preservative propolis in food preservation

in recent years, with the deepening understanding of food safety, people have an increasingly strong desire for natural and safe food. In the process of production, processing, storage, transportation and sales, food is easy to be polluted by microorganisms due to the influence of external environmental factors, which will deteriorate and then lose its edible value, causing economic losses, and even producing toxins to endanger human health. As a natural substance, propolis not only contains various bioactive ingredients beneficial to human body, but also has high-efficiency and broad-spectrum antibacterial effect, which can be added to various foods as a preservative

1 chemical composition and physiological function of propolis

propolis is a kind of resin material collected by bees from the axillary buds or flower buds of new branches of plants, mixed with the secretion of its tongue gland and wax gland, and repeatedly metabolized by bees. It contains a large number of flavonoids and terpene compounds, as well as enzymes, lipids, alcohols, aldehydes, phenols, ethers, organic acids, a large number of amino acids Poly amino acids have also become a hot research field at home and abroad in the past 210 years, vitamins and other substances. Propolis has the functions of sterilization and anti-inflammatory, removing toxins, strengthening immune function, reducing blood lipids and blood glucose. It can prevent and treat tumors, cardiovascular and cerebrovascular diseases, diabetes and gastrointestinal diseases, protect hepatocytes, prevent liver cirrhosis, promote endocrine activities, improve tissue metabolism, regulate autonomic nervous function and other health functions

2 mechanism of propolis preservation

2.1

antibacterial ability

propolis has strong antibacterial and bactericidal ability. Its antibacterial ability is due to the existence of flavonoids, aromatic acids and their esters in the resin [1]. Researchers from Kazan Veterinary College of the former Soviet Union first confirmed the antibacterial activity of propolis. It can inhibit nearly 20 kinds of bacteria, such as Staphylococcus aureus, Streptococcus, Bacillus subtilis, Salmonella, Escherichia coli, acid resistant bacteria, especially Gram-positive bacteria. Kedzia's study showed that 1mg/ml propolis ethanol extract can highly inhibit 267 anaerobic bacteria [2]. In addition, propolis also has a strong inhibitory effect on yeast and mold. Ozcan et al. Studied the antifungal properties of propolis, and compared the inhibition of propolis aqueous extract with different concentrations on Penicillium, streptospora, Alternaria, applecarpa and Botrytis in the culture medium. The experiment found that 4% of the bolts with grade 8.8 and above were made of low-carbon alloy steel or medium carbon steel, and the antibacterial rate of propolis aqueous extract with heat treatment (quenching and tempering) concentration on the above bacteria was more than 50% [3]. Koo et al. Measured the antibacterial effect of propolis by agar diffusion method, and found that propolis had a good effect on Candida, Staphylococcus, Enterococcus, Streptococcus and actinomycetes. Among them, the inhibition radius of

to actinomycetes was the largest, and it was not affected by the medium matrix [4]. Yang Yanbin et al. Showed that the order of inhibition of propolis on various microorganisms was: Staphylococcus aureus> Bacillus cereus> Bacillus subtilis> Escherichia coli; Fungi: Mucor> Rhizopus nigrum> Fusarium oxysporum> Aspergillus niger> Penicillium; Yeast: beer yeast> abnormal Hansen's yeast> Candida [5]

2.2

film forming property and antioxidant effect

propolis is a resin substance with high viscosity. When it is coated on the surface of food, it will form a very thin film, which can isolate oxygen, block microorganisms, reduce water evaporation, reduce respiratory intensity and metabolism, reduce the consumption of nutrients, so as to prolong the preservation time of food and prevent its corruption and deterioration. In addition, a large number of flavonoids contained in propolis have the effects of scavenging free radicals and antioxidation, and have a better protective effect on the functional components in food. Hu Feng of Zhejiang Jinhua Bee Products Research Institute found that after applying propolis ethanol extract of a certain concentration to the surface of citrus and storing it in natural air drying baskets for 147 days, the average water loss rate of Citrus in the test group was 15.2%, while that of the control fruit was 20.71%, the lowest rotten fruit rate in the test group was 2.53%, and that of the control group was 16.7%, indicating that the effect of propolis delayed the time of Citrus wilting and corruption [6]. According to Zhao Ying and others, ginseng treated with 0.07% and 0.12% propolis preservative can be stored for more than 1 year, with a damage rate of 2 ~ 4%. The saponin content is only 0.6 ~ 0.65% lower than that of fresh water ginseng, and the total amount of amino acids is 0.25 ~ 0.49%. The difference is not obvious [7]

3 application of propolis in food preservation

han et al. Studied the effect of propolis alcohol extract and water extract on pork protein and fat preservation, and found that both propolis alcohol extract and alcohol extract can effectively prevent fat oxidation and protein enzymatic hydrolysis, but the preservative effect of water extract is better than alcohol extract, so propolis extract has good preservative effect on meat products [8] [9]. Ejnawawy et al. Studied the effect of propolis on the flora system in yogurt, and found that propolis can effectively inhibit the pathogenic bacteria of skimmed milk and yogurt [10]

was 2.25%, and the egg yolk outline was obvious without serious defects; While in the control group, when stored for 60 days, the protein was watery, all turned black, rotten and inedible. The preservation time of 1.6% and 2.2% alcohol extract is 8. Therefore, for the development of sealing machine in the market, the preservation time of 0 days, 3.9% alcohol extract is 90 days, and the preservation time of 7.3% and 15.9% alcohol extract is 100 days [11]

Song Xinfang studied the influence of different application methods of propolis on the fresh-keeping effect of eggs, and pointed out that spraying had better fresh-keeping effect than dipping. He used propolis as the main material to make a preservative for the preservation of fruits and vegetables. With the rotten fruit rate and weight loss rate as the monitoring indicators, he tested the effects of treatment methods and drug concentration on the preservation time of apples, tomatoes and vegetable peppers. The results showed that compared with the control group, the rotten rate of apples in the experimental group (high concentration group and low concentration group) was reduced by 7.94% and 6.06%, and the weight loss rate was reduced by 13.88% and 11.00%; The rotten fruit rate of tomatoes was reduced by 62.09% and 59.68%, and the weight loss rate was reduced by 51.55% and 50.33%; Vegetable pepper reduced the rotten fruit rate by 12.07% and 6.27%, and the weight loss rate by 25.95% and 12.22% [12]

Tang Fengxia et al. Conducted a preliminary study on the effect of propolis on fresh pork, and found that propolis alcohol extract had a good fresh-keeping effect on fresh pork. The pork fresh-keeping with 8% propolis liquid can also be kept fresh after using parallel interface and serial interface for 6 hours. The muscle is red, the fat is white, and the pH value does not change significantly. Hydrogen sulfide, volatile base nitrogen, peroxidase and other indicators meet the national first-class fresh meat standard. The test results showed that the control group maintained the general freshness for about 12 hours, the 4% propolis solution for about 24 hours, and the 8% propolis group could keep fresh for 40 hours, and the pork preserved with propolis kept the taste and flavor basically unchanged [13]. Yang Yanbin et al. Used 10% propolis instead of chemical preservatives in the production of royal jelly honey to maintain the pure natural state of the product [14]

4 conclusion

to sum up, propolis can have a good fresh-keeping effect at a low concentration, which is of great significance for perishable foods, especially some foods with high added value and high physiological activity. In addition, propolis also has health care effects. Therefore, as a kind of natural food preservative beneficial to human body, propolis has broad development prospects