Physical stability improvement and digestion behavior evaluation of yogurt by incorporating cinnamaldehyde-loaded whey protein microcapsules

An alternative approach to improve the physical stability of yogurt was developed by introducing cinnamaldehyde (CA)-loaded whey protein concentrate microcapsules (CA microcapsules). The effects of CA microcapsules on the physicochemical properties of whey protein-enriched set-yogurt during fermentation and post-ripening and the gastric digestion behavior were evaluated. The results showed that CA microcapsules were effective in controlling pH reduction during fermentation, mitigating post-acidification and enhancing gel density in yogurt. Addition of CA microcapsules (CA level at 0.25 % in oil phase) significantly improved the water holding capacity by 19 %, enhanced storage stability and preserved the activity of lactic acid bacteria (LAB). Digestion studies using in vitro dynamic human stomach model indicated that CA microcapsules had no effect on pH changes or microstructure during gastric digestion, promoted protein gastric emptying rate (89.29 %), increased the protein hydrolysis rate and provided a protective effect on LAB. Therefore, incorporation of flavor CA microcapsules can be a promising strategy to enhance the physical stability of yogurt.