摘要
将不同添加量的植物乳杆菌(Lactobacillus plantarum)NMGL2胞外多糖(EPS)与菌株NMGL2混合培养,考察EPS对菌株NMGL2生长、形态和稳定性的影响,并将其应用于菌株NMGL2发酵乳加工中,研究其对发酵乳加工特性的影响。结果表明,EPS能促进菌株NMGL2的生长,EPS添加量为4%的效果最佳,培养24 h后,活菌数达4.3×109 CFU/mL;扫描电镜观察发现添加EPS后菌体之间出现黏连现象,细胞形态发生不规则变化,并且EPS附着于菌体表面,降低了体系Zeta电位及稳定性。菌株NMGL2发酵过程中,EPS对菌株NMGL2的产酸及发酵乳的内聚性无显著影响(P>0.05),但能显著提高发酵乳样品的弹性和黏性、降低其流动性和硬度(P<0.05)。因此,植物乳杆菌NMGL2 EPS能够有效改善发酵乳加工特性,为产EPS植物乳杆菌在发酵乳制品中的应用提供技术依据。
Effects of extracellular polysaccharide(EPS)produced by Lactobacillus plantarum NMGL2 on the growth,morphology and stability of strain NMGL2 were investigated by mixed culture of different addition of EPS and strain NMGL2,and it was applied to the processing of fermented milk by strain NMGL2,and the effect on the processing characteristics of fermented milk was studied as well.The results showed that EPS could promote the growth of strain NMGL2,and the effect was the optimal with the 4%addition of EPS.The viable bacteria count reached 4.3×109 CFU/ml after 24 h of culture.Scanning electron microscopy showed that the adhesion phenomenon occurred between the bacteria after the addition of EPS,cell morphology changed irregularly,and EPS adhered to the bacterial surface,which reduced the Zeta potential and stability of the system.In the fermentation process of strain NMGL2,EPS had no significant effect on the acid production of strain NMGL2 and the cohesion of fermented milk(P>0.05),but it could significantly improve the elasticity and viscosity of fermented milk sample,and reduce its fluidity and hardness(P<0.05).Therefore,L.plantarum NMGL2 EPS could effectively improve the processing characteristics of fermented milk,providing a technical basis for the application of EPS-producing L.plantarum in fermented dairy products.
作者
赖田甜
赵华
姚梦柯
朱晨
张敏
杨贞耐
LAI Tiantian;ZHAO Hua;YAO Mengke;ZHU Chen;ZHANG Min;YANG Zhennai(Beijing Engineering and Technology Research Center of Food Additives,Beijing Advanced Innovation Center for Food Nutrition and Human Health,Beijing Technology and Business University,Beijing 100048,China)
出处
《中国酿造》
CAS
北大核心
2022年第2期113-118,共6页
China Brewing
基金
2021年研究生科研能力提升计划项目(19008021085)
北京市自然科学基金面上项目(6192004)。
关键词
胞外多糖
植物乳杆菌NMGL2
发酵乳
加工特性
exopolysaccharide
Lactobacillus plantarum NMGL2
fermented milk
processing properties
