Study On Biological Activity Of Fermented Milk Containing Alcohol

Alcohol-containing fermented milk is an important member of the traditional fermented milk family.It is a kind of alcoholic milk beverage containing acid,alcohol,aromatic substances and a small amount of carbon dioxide,which is fermented naturally by lactic acid bacteria and yeast.Due to the lack of in-depth study on the functional strains and fermentation mechanism of traditional alcoholic fermented milk,industrialized production has not been achieved so far.Although the biological activity and health function of traditional alcoholic fermented milk have been recognized by the public,the research on its biological activity mechanism is still rare.Based on the co-fermentation system of lactic acid bacteria and yeast,the biological activity of fermented milk fermented by different strains was studied in vitro and in animal experiments.The results are as follows:1.Based on the co-fermentation system of specific lactic acid bacteria and yeast,sensory evaluation and tissue state were taken as indexes to optimize the production process.The industrialized production technology of alcoholic fermented milk was successfully developed.The technology added 0.1%pectin,0.45%acid-resistant carboxymethyl cellulose sodium FL100,0.02%A to 3%skimmed whey powder and30%milk raw milk.After 6 hours of fermentation at 35?150 rpm,the viscosity of fermented milk containing alcohol was 1.48 Pa.S,the centrifugal rate was 6.8%+0.1%,and the sensory effect was the best,with a score of 94.0.2.The ACE inhibitory activity,antioxidant activity and antimicrobial activity of alcohol-containing fermented milk?WPC?,yoghurt?HM?and yoghurt?CM?were determined in vitro.The in vitro bioactivity of lactic acid bacteria and yeast symbiotic fermentation samples was higher than that of single lactic acid bacteria or yeast fermentation milk samples.The ACE inhibitory activity and antioxidant activity of WPC supernatant samples fermented by lactic acid bacteria and yeast were 90.41%and0.84 mM Trolox,respectively.The ACE inhibitory activity and antioxidant activity of WPC supernatant samples fermented by lactic acid bacteria alone were 90.41%and0.84 mM Trolox,respectively.The ACE inhibitory and antioxidant activities of the aseptic supernatant from WPC fermented by yeast alone were 85.76%and 0.17 mM Trolox,respectively.Among the above three samples,the MIC₅₀ of symbiotic fermented WPC supernatant for Shigella flexneri CMCC?B?51572,Salmonella paratyphi B CMCC?B?50094,Bacillus cereus CMCC?B?63303,Escherichia coli ATCC 25922,Staphylococcus aureus ATCC 25923,Pseudomonas aeruginosa ATCC27853 were 0.06 g/mL,0.03 g/mL,0.05 g/mL,0.46 mg/mL,0.42 g/mL and 0.24 g/mL.The MIC₅₀ of the sterile supernatant from WPC fermented by lactic acid bacteria and yeast was lower than that from WPC fermented by lactic acid bacteria alone.3.The effects of fermented milk on vascular endothelial cell function in rats were studied.The results showed that the endothelial cells of rats had no obvious dose-dependence on different fermented milk samples.Fermented WPC samples treated for24 hours promoted NO production in rat endothelial cells.The NO content ranged from65.7 mg/mL to 172.24 mg/mL,which was 11.3²9.7 times higher than that of untreated WPC samples.WPC raw milk fermented by lactic acid bacteria alone,yeast alone and lactic acid bacteria and yeast symbiotic fermentation of fermented milk components,supernatant components can promote the production of bradykinin on rat endothelial cells.4.The effects of alcohol-containing fermented milk on blood pressure and related physiological indexes in spontaneously hypertensive rats were studied.The results showed that the sterile supernatants of three kinds of fermented milk had a certain blood pressure regulation effect on SHR.Among them,yoghurt had the most obvious effect on lowering blood pressure.After 6 weeks of feeding,the systolic blood pressure?SBP?,diastolic blood pressure?DBP?and heart rate decreased by 20.5 mm Hg,16.8 mmHg and 45.8 times/min.During 8 weeks of intragastric administration,HM?LAB+Yeast?,CM?LAB+Yeast?and WPC?LAB+Yeast?had no effect on the normal growth of WKY,and showed hypotensive effect on SHR.Among them,HM?LAB+Yeast?had the best effect.After 8 weeks of intragastric administration,compared with SHR in 0.9%NaCl group,the ACE inhibitory activity,NO content and bradykinin content in serum of SHR in HM?LAB+Yeast?,CM?LAB+Yeast?and WPC?LAB+Yeast?groups increased significantly;the left ventricular index of SHR in Captopril,HM?LAB+Yeast?,CM?LAB+Yeast?and WPC?LAB+Yeast?groups decreased significantly,but in Captopril group,the left ventricular index of SHR decreased significantly.The serum levels of uric acid,creatinine,urea nitrogen,glutamic oxalate transaminase and alanine transaminase in HR increased significantly.One week after stopping gastric administration,SBP in HM?LAB+Yeast?,CM?LAB+Yeast?and WPC?LAB+Yeast?groups did not increase significantly.