Sheu T Y, Marshall R T, Heymann H
Food Science and Human Nutrition, University of Missouri, Columbia 65211.
J Dairy Sci. 1993 Jul;76(7):1902-7. doi: 10.3168/jds.S0022-0302(93)77523-2.
Lactobacillus bulgaricus cells were entrapped in beads of calcium alginate and evaluated for their ability to survive freezing processes. Cells survived freezing (without agitation) in ice milk mix much better than in distilled water, and more entrapped cells survived than did cells that were not entrapped. Glycerol and mannitol were cryoprotective, but glucose was not, when each was added (6%) separately to the beads. Entrapment protected the lactobacilli in batch frozen and continuously frozen ice milk mixes. The percentage of survival for entrapped and unentrapped cells in continuously frozen ice milk approximated 90 and 40%, respectively. Lactobacilli survived better in beads with mean diameters > 30 microns than in those averaging 15 microns. Addition of entrapped lactobacilli had no measurable effect on the sensory characteristics of the ice milk.
保加利亚乳杆菌细胞被包埋在海藻酸钙珠中，并对其在冷冻过程中的存活能力进行评估。细胞在冰牛奶混合物中冷冻（无搅拌）时的存活情况比在蒸馏水中好得多，并且被包埋的细胞比未被包埋的细胞存活得更多。当甘油和甘露醇分别以6%的比例添加到珠子中时具有冷冻保护作用，但葡萄糖没有。在分批冷冻和连续冷冻的冰牛奶混合物中，包埋可保护乳酸菌。在连续冷冻的冰牛奶中，被包埋和未被包埋细胞的存活率分别约为90%和40%。平均直径大于30微米的珠子中的乳酸菌比平均直径为15微米的珠子中的乳酸菌存活得更好。添加包埋的乳酸菌对冰牛奶的感官特性没有可测量的影响。
