Improving the stability and digestive property of Bifidobacterium bifidum encapsulated in whey protein isolate/pectin emulsions

Bifidobacterium bifidum (B. bifidum) is considered as one of the most important intestinal probiotics for its health benefits. However, the survival of B. bifidum is typically hindered by a number of factors, including pH and heating, which constrains the potential applications of B. bifidum in food products and the realization of its beneficial effects. In this study, B. bifidum was encapsulated in emulsions prepared from whey protein isolate (WPI) and pectin. The microscopic morphology of the emulsions was observed by Cryo-scanning electron microscopy (Cryo-SEM) and transmission electron microscopy (TEM) as well as ultra-high resolution microscopy (URM). The pH, ionic strength, and thermal stability of the emulsions are recorded best on 2 % pectin concentration as compared to 1 % or 3 %. The viability of B. bifidum is enhanced by encapsulation in emulsion after in vitro digestion compared to free B. bifidum. The findings indicate that emulsion encapsulation can be an effective method for maintaining the activity of probiotics, which could be a valuable approach for developing orally consumed probiotic foods.