摘要
为了提高干酪乳杆菌CCFM711的冻干存活率及冻干粉的耐酸性,测定了不同耐酸性壁材冻干菌体后的耐酸性,以及菌体在不同种类糖与蛋白质保护下的冻干存活率。将壁材与冻干保护剂复配制备冻干菌粉,测定菌体冻干存活率和耐酸性,并与优化乳化法制备的海藻酸钠微胶囊进行比较,对真空冷冻干燥制备干酪乳杆菌耐酸冻干粉的工艺进行优化。以水苏糖作为冻干保护剂分别复配海藻酸钠、酪蛋白酸钠制备冻干菌粉能够同时提高其冻干存活率与耐酸性。以水苏糖作为冻干保护剂,制备海藻酸钠湿微胶囊能够显著提高菌体在酸性环境中的存活率,但冻干后其耐酸性显著降低,仅为(0.37±0.28)%,不及非微胶囊冻干粉[(19.56±1.83)%]。以水苏糖(100 g/L)作为冻干保护剂,酪蛋白酸钠(10 g/L)为耐酸壁材,菌悬液与水苏糖-酪蛋白酸钠混合溶液以体积比2∶5混合时,其冻干存活率为(59.43±6.28)%,pH 2.5下处理2 h,存活率达(34.16±7.18)%,耐酸性显著高于无壁材冻干粉。该研究可为制备干酪乳杆菌耐酸冻干粉提供指导。
In order to improve the freeze-drying survival rate and the acid resistance of lyophilized powder of Lactobacillus casei CCFM711,cells were lyophilized with different acid-resistant materials,and with sugars and proteins as protectants for freeze-drying.The lyophilized cell powder was then tested and compared with the sodium alginate microcapsules prepared by the optimized emulsification method.Finally,the vacuum freeze-drying process was optimized.The results showed that stachyose combined with sodium alginate and sodium caseinate,respectively,could simultaneously improve the survival rate in freeze-drying and the acid resistance.Using stachyose as protectant for freeze-drying in preparation of sodium alginate wet microcapsules,the survival rate of bacteria in acidic environment could be significantly improved,but the acid resistance was significantly reduced,which was only(0.37±0.28)%,much less than un-coated lyophilized powder(19.56±1.83)%.Stachyose(100g/L)was used as the protectant for freeze-drying,and sodium caseinate(10 g/L)as the optimal wall material.Mixing the bacterial suspension and the protectants at the ratio of 2∶5,a freeze-drying survival rate of(59.43±6.28)%was obtained,while the highest survival rate was(34.16±7.18)%after 2 hours'treatment at pH 2.5,about 8 times of the control.This study provides guidance for the preparation of lyophilized powder of L.casei.
作者
欧阳碧妍
崔树茂
毛丙永
唐鑫
马方励
赵建新
张灏
陈卫
OUYANG Biyan;CUI Shumao;MAO Bingyong;TANG Xin;MA Fangli;ZHAO Jianxin;ZHANG Hao;CHEN Wei(School of Food Science and Technology,Jiangnan University,Wuxi 214122,China;Infinitus(China)Co.,Ltd,Guangzhou 510623,China)
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2020年第13期62-68,共7页
Food and Fermentation Industries
基金
国家食品科学与工程一流学科建设项目(JUFSTR20180102)。
关键词
干酪乳杆菌
冻干粉
耐酸性
冻干存活率
微胶囊
Lactobacillus casei
lyophilized powder
acid-resistance
freeze-drying survival rate
microencapsulation
