CAJ | 학술논문

保加利亚乳杆菌B9（Lactobacillus delbrueckii subsp.bulgaricus B9）是一株具有优良酸乳发酵性能的乳杆菌。为开发B9菌株活性，为工业化发酵剂生产提供稳定菌种，本研究利用液氮深冷的方式对B9菌株进行冷冻保藏。以冷冻存活率评价指标，在对冷冻保护剂种类进行筛选，对保护剂配方进行正交优化，并确定菌体与保护剂最佳混合比例。结果表明，脱脂乳粉、甘油、海藻糖及Vc四种保护剂能对保加利亚乳杆菌B9起到良好的保护作用；正交优化确定保护剂配方为脱脂乳粉10%、甘油3%、海藻糖5%、Vc 0.075%（m：m），可使菌体解冻后存活率达到91%。
보가리아유간균B9（Lactobacillus delbrueckii subsp.bulgaricus B9）시일주구유우량산유발효성능적유간균。위개발B9균주활성，위공업화발효제생산제공은정균충，본연구이용액담심랭적방식대B9균주진행냉동보장。이냉동존활솔평개지표，재대냉동보호제충류진행사선，대보호제배방진행정교우화，병학정균체여보호제최가혼합비례。결과표명，탈지유분、감유、해조당급Vc사충보호제능대보가리아유간균B9기도량호적보호작용；정교우화학정보호제배방위탈지유분10%、감유3%、해조당5%、Vc 0.075%（m：m），가사균체해동후존활솔체도91%。
To improve the preparation technology of direct vat set in industrial production, the liquid nitrogen cryogenic treatment was used in the preparation ofLactobacillus bulgaricus B9 starter. The optimal formula of freeze protectant, which was determined with screening different kinds of freeze protectant by single-factor experiments and optimizing the concentration of preferred freeze protectant by orthogonal test were skim milk powder 10%, Glcerol 3%, Trehalose 5%, Vc 0.075%(m:m). The viability of bacteria cells can reach 92% after freezing with our freeze protectant.