The functional food development by adding probiotic bacteria is getting a lot of concern. In this study, Bifidobacterium bifidum AS was encapsulated in calcium-alginate 2 % w/v (C sample) or the mix of calcium-alginate 2 % (w/v) and whey protein 1 % (w/v) (CW sample) or calcium-alginate 2 % (w/v) coated by whey protein 1 % (w/v) (CcW sample) by extrusion method, and added to mayonnaise product. The pH changes, the survival rate of probiotic bacteria, and total yeast and mold count during storage, as well as the probiotic survival in simulated gastric medium, were evaluated. The result showed that the pH changes were not significantly different in all mayonnaise samples in this test. The viability of the free probiotic cell was significant decrease by log CFU/g compared to ÷ log CFU/g in encapsulated cell samples after four weeks of storage. None of the free cells survived after six weeks of storage. The total yeast and mold count in samples related to the probiotic count, the viability of probiotic cells higher 6 log CFU/g might be controlling the growth of yeast and mold in mayonnaise. Whey protein has been shown to significantly improve the survival rate of B. bifidum and calcium-alginate coated by whey protein, indicating the most effective protection. | Study on the effect of Calcium-alginate and whey protein on the survival rate of Bifidobacterium bifidum in Mayonnaise