摘要
本研究拟筛选对单增李斯特菌具有显著抑制作用的乳酸菌,探究乳酸菌抑菌物质的分布、热稳定性、pH稳定性、蛋白酶敏感性;测定该乳酸菌生长曲线及最小抑菌浓度。最后初步应用于杜黑猪肉冷藏保鲜,通过感官评价、pH、肉色、菌落总数、总挥发性盐基氮和硫代巴比妥酸值评价其保鲜效果。结果表明,来源于泡菜汁中一株副干酪乳杆菌Lab5对单增李斯特菌的抑制效果显著,抑菌圈直径达38.28±1.97 mm,抑菌物质存在于发酵上清液(CFS)中,CFS经60~121℃处理25 min,其对单增李斯特菌和大肠杆菌抑菌圈直径分别超过32.07±2.1 mm、11.53±0.44 mm;pH3.0~8.0范围内抑菌活性无显著性差异(P>0.05);蛋白酶K处理对抑菌活性影响最大,其对单增李斯特菌抑菌圈直径减小了7.69 mm;表明副干酪乳杆菌Lab5 CFS具有良好的热稳定性、pH稳定性,对六种蛋白酶(糜蛋白酶、胰蛋白酶、肠激酶、蛋白酶K、木瓜蛋白酶、胃蛋白酶)较不敏感。在应用于杜黑猪肉冷藏保鲜发现,副干酪乳杆菌Lab5后生元处理组(2MIC和4MIC组)与对照组相比,冷藏9 d时肉品的菌落总数显著降低了99.7%,pH下降了0.33,硫代巴比妥酸反应物分别减少0.66 mg/kg、0.91 mg/kg(P<0.05);延长了货架期2 d。感官评分也表明其起到护色、改善气味的作用,延缓猪肉感官质量的下降。特别是4MIC后生元组在各项保鲜指标显示出更好的保鲜效果。以上研究结果表明,副干酪乳杆菌Lab5株后生元成分作为一种新型天然、安全的生物防腐剂,在肉类保鲜领域具有重要的应用潜力,对提升食品安全具有重要的理论和实际意义。
In this study,the screening of lactic acid bacteria with significant inhibitory effect on Listeria monocytogenes.It was determined that the inhibitory substances existed in cell-free fermentation supernatant(CFS),cell pellet or bacterial lysate.The thermal stability,pH stability,and protease sensitivity of the inhibitory substances were investigated.The growth curve and the minimum inhibitory concentration(MIC)of the selected strain were also determined.Finally,the preliminary application was in the cold storage and preservation of Duhei pork.The preservation effect was evaluated by sensory evaluation,pH,meat colour,viable cell counts,total volatile basic-nitrogen(TVB-N)and thiobarbituric acidreactive substances(TBARS).The experimental results showed that a strain of Lacticaseibacillus paracasei Lab5 from pickle juice showed notable inhibition of Listeria monocytogenes,with an inhibition zone diameter of 38.28±1.97 mm,the inhibitory substances were present in the CFS,which was treated at 60~121℃for 25 min,and its inhibition zone diameter of inhibition against Listeria monocytogenes and Escherichia coli still reached more than 32.07±2.1 mm and 11.53±0.44 mm.No significant difference in bacteriostatic activity in the pH 3.0~8.0(P>0.05).Proteinase K treatment had the greatest effect on the inhibitory activity,as it reduced the diameter of the circle of inhibition of Listeria monocytogenes by 7.69 mm;It was shown that Lacticaseibacillus paracasei Lab5 CFS had good thermal、pH stability and was less sensitive to six proteases(chymotrypsin,trypsin,enterokinase,proteinase K,papain,pepsin).In the preservation application of refrigerated Duhei pork,it was found that at 9 d of refrigeration,Lacticaseibacillus paracasei Lab5 postbiotics treatment groups(2MIC and 4MIC groups)had significantly reduced the viable cell counts of the meat by 99.7%compared to the control,decreased the pH by 0.33,and reducing TBARS reactants by 0.66 mg/kg,and 0.91 mg/kg in meat(P<0.05),and prolonged the shelf-life by 2 d,when compared with the control group.The scores of sensory testing also indicated that it played a role in color protection,improved the odor and delayed the deterioration of the sensory quality of refrigerated pork.In particular,the 4MIC group showed better effects in all freshness indicators.It's concluded that the postbiotic of Lacticaseibacillus paracasei Lab5,as a new type of natural and safe biological preservative,has an important potential for application in the field of meat preservation,which is of great theoretical and practical significance for the enhancement of food safety.
作者
王盼
李林峰
黄文艺
吴艳丽
张浩峰
刘小容
胡文锋
胡斌
李雪玲
WANG Pan;LI Linfeng;HUANG Wenyi;WU Yanli;ZHANG Haofeng;LIU Xiaorong;HU Wenfeng;HU Bin;LI Xueling(College of Food Science,South China Agricultural University,Guangzhou 510642,China;College of Animal Science of South China Agricultural University,Guangzhou 510642,China;Bioforte Biotechnology(Shenzhen)Co.,Ltd.,Shenzhen 518118,China;Institute of Animal Science,Guangdong Academy of Agricultural Sciences/State Key Laboratory of Swine and Poultry Breeding Industry/Guangdong Key Laboratory of Animal Breeding and Nutrition,Guangzhou 510640,China)
出处
《食品工业科技》
北大核心
2026年第4期238-247,共10页
Science and Technology of Food Industry
基金
广东省科技计划项目资助(2022B0202110001)
华南农业大学校企合作横向项目“畜禽微生物资源发掘、评鉴与应用”(H230386)。
关键词
副干酪乳杆菌Lab5
后生元
单增李斯特菌
杜黑猪肉
保鲜
Lacticaseibacillus paracasei Lab5
postbiotics
Listeria monocytogenes
Duhei pork
preservation
