Meanwhile, the number of microencapsulated cells in the one-layer treatment decreased to the same level of 109 CFU g 1 at the 6th day and in the double-layer treatment decreased to 109 CFU g 1 at the 8th day, which reflected the role of whey protein as coating and protecting material for cells at one-layer treatment in addition to the sodium alginate as extra layer of protection for the cells in the double-layer treatment.