黑粒小麦花青素抑菌性及其对冷却猪肉保鲜效果

Bacteriostatic Activity of Black-Grained Wheat Anthocyanins and Its Preservation Effect on Chilled Pork

为研究黑粒小麦花青素的抑菌性及其对冷却猪肉的保鲜作用,考察黑粒小麦籽粒花青素对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌的抑菌能力、最小抑菌质量浓度及其与对羟基苯甲酸乙酯、山梨酸单独和混合使用的抑菌效果;测定黑粒小麦花青素对冷却猪肉色差值、持水力、pH值、硫代巴比妥酸反应物(thiobarbituric acid reactive substances,TBARS)值、总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、产H2S能力和菌落总数的影响。结果表明:黑粒小麦花青素对不同细菌表现出独特的抑制效果,效果强弱依次为金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌;其最小抑菌质量浓度分别为1.25、5、10 mg/mL。随着贮藏时间的延长,无菌蒸馏水、40 mg/mL花青素、40 mg/mL花青素+5 μg/mL山梨酸、5 μg/mL山梨酸4种处理下的猪肉亮度值、红度值和持水力均显著降低(P<0.05),其中花青素+山梨酸组色泽最好,持水力最大。冷却猪肉pH值、TBARS值、TVB-N含量和菌落总数则随着贮藏时间延长而增加,保鲜处理组显著低于对照组(P<0.05)。H2S实验中,冷却猪肉随贮藏时间延长表现出阳性,保鲜处理组呈阳性的时间迟于对照组。保鲜能力依次为花青素+山梨酸>山梨酸>花青素>蒸馏水。综上所述,黑粒小麦花青素具有一定的抑菌和保鲜效果,但效果略差于山梨酸,与其混合使用效果最佳。

In order to study the bacteriostatic activity of black-grained wheat anthocyanins and its preservation effect on chilled pork,the antibacterial ability and minimum inhibitory concentration(MIC)of black-grained wheat anthocyanins against Escherichia coli,Staphylococcus aureus,and Bacillus subtilis,and the bacteriostatic effect of its combination with ethylparaben or sorbic acid were analyzed.The effects of black-grained wheat anthocyanins on the color difference,water retention capacity,pH,thiobarbituric acid reactive substances(TBARS)value,total volatile basic nitrogen(TVB-N)content,H2S production,and total viable count of pork during low temperature storage were determined.The results showed that the antibacterial activity of black-grained wheat anthocyanins decreased in the order of S.aureus>B.subtilis>E.coli,with MIC values of 1.25,5,and 10 mg/mL,respectively.With increasing storage time,the brightness,redness,and water retention capacity of pork samples treated with sterile distilled water(control),40 mg/mL anthocyanins,40 mg/mL anthocyanins+5μg/mL sorbic acid,or 5μg/mL sorbic acid significantly decreased(P<0.05),the combined treatment exhibiting the most desirable color and the highest water retention capacity.Conversely,the pH,TBARS value,TVB-N content,and total bacterial count increased,being significantly lower in the preservation groups than in the control group(P<0.05).H2S production increased with storage time,and the time to become positive for H2S was delayed in the preservation groups compared with the control group.The preservation effects on chilled pork decreased in the order of anthocyanins+sorbic acid>sorbic acid>anthocyanins>control.In conclusion,black-grained wheat anthocyanins had bacteriostatic and preservative effects, which were slightly less pronounced than those of sorbic acid, but their combinationwas the most effective.