The Bactriostasis Of Propolis And The Applied Study On The Keeping Freshness Of Meat And Meat Products

Food preservation, especially for low acid food, such as meat and meatproducts, has always been a keen problem need to be solved in food industry. Propolis,claimed to be medicines for swarm of bees, is a kind of natural product that possessesthe biological characteristic of anti-oxidation, antiviral property, anti-bacteria,anti-fungus, anti-tumour, anti-protozoan and improving immune ability. Therefore,propolis has been widely used in the field of agriculture, medicine, food and cosmeticprocessing. This subject is mainly focus on the properties of propolis and its application inmeat and meat products preservation. 1. The inhibition ability of extracted propolis in alcohol on micro-organismsnaturally present in food was studied. The concentration of extracted propolis solutionapplied in experiment were 0.5%,1.5%,2.0%,2.5%,3.0%, respectively. Theintensive inhibition activity of propolis on S.aureus, Cl.botulinum, Shigella, B.subtiliswas observed, and the inhibition effect increased with increasing concentration ofpropolis. However, there is no obvious inhibitioneffecton E.coli was found. 2. Total bacterial populations, pH and TVB-N values were determined after freshpork was treated by 1.0%, 1.5% and 2.0% extracted propolis solution and subsequentto refrigerated storage at 7℃ (±０．５℃). Packaged in air, microbial spoilage (usually107CFU/g) was reached at 15, 18 and 21days, respectively (as opposed to 9 days forcontrol). And for packaged under vacuum, microbial spoilage occurred at 21, 23 and25 days, respectively (6 days for control). The lower TVB-N values for treatmentsamples were also observed, but the variation trend was different from total bacterialpopulations. Sensory properties were also evaluated, the result showed that all thesamples treated by extracted propolis solution were better than controls.3. The total bacterial populations of red sausages were tested during storage at 7℃ (±0.5℃) by prior treatment in 1.0%,1.5%,2.0% extracted propolis solution. Theresults showed that the microbial spoilage was reached at 19, 20 and 21 days,respectively, (as opposed to 10 days for control). Sensory evaluation also showed asimilar result. 4. The effect of extracted propolis solution that heated at 80℃,100℃,120℃ for30min on meat preservation properties was studied. The result showed that there wasno significant effect on meat preservation properties when the extracted propolissolution heated at 80℃. However, a marked effect was observed when the solutionwas heated at 100℃ and 120℃, and the negative effect increased with increasingheat temperature.