Study of the survival rate of free and microencapsulated Lactobacillus acidophilus La5 in Iranian white cheese during manufacture and storage

Microencapsulation of probiotic cells is one of the newest method which increasesprobiotics survival in probiotic food products. The aim of this study was to investigate thesurvival rate of free and microencapsulated lactobacillus acidaphilus La5 by sodium alginateand resistant starch in Iranian white chesses during manufacturing proccess and storage time.Two types of probiotic cheese, with free bacteria and microencapsulated bacteria, were manufactured in a same situation. The numbers of viable cells during 182 days of storage in refrigerated conditions, with a two weeks interval in two types of cheese using culture method were counted. In the operation was repeated six times and the obtained data were analyzed with SPSS software. In day zero, the average number of viable cells of Lactobacillus acidophilus in cheese containing free bacteria (10±0.58 log cfu/g) was less than cheese containing the microencapsulated microencapsulated bacteria (12.32±0.35 log cfu/g), however during the 28 days maintenance period, the number of viable cells in both types of cheese increased. The average number of cells in cheese containing free cells (12.09±0.59 log cfu/g) increased more than cheese containing microencapsulated cells (12.59±0.23 log cfu/g).Number of viable cells of Lactobacillus acidophilus reduced significantly from days 28 to182 of storage in both type of cheeses, but this reduction in cheese containing free cells(5.1±0.67 log cfu/g) were significantly higher than cheese containing microencapsulated cells (11±0.58 log cfu/g) (p<0.01). According to the results of this study, microencapsulation process by sodium alginate gel and resistant starch is able to increase the survival rate of lactobacillus acidaphilus La5 in Iranian white cheese after 6 month of storage time.