Gel properties of curcumin-fortified Lactobacillus helveticus MB2-1 fermented milk and its gastrointestinal digestion in vitro

The functional properties of foods are closely related with its matrix. This study examined the impact of curcumin-fortified Lactobacillus helveticus MB2-1 fermented milk gel on the intestinal lipid digestion and bioaccessibility of curcumin through dynamic digestion method. The gel properties, microstructure, oil droplets stability, free fatty acid (FFA) release and curcumin bioaccessibility during digestion of the curcumin-fortified milk gels fermented by L. helveticus MB2-1 or tradition commercial starters (Streptococcus thermophilus and Lactobacillus bulgaricus) were investigated and compared. The curcumin-fortified L. helveticus MB2-1 fermented milk gel was found to present higher apparent viscosity, more thicker properties, and firmer texture, which affect the gastrointestinal digesta status together with the release of oil droplets and solubilized curcumin, promote lipid digestion as well as enhance the bioaccessibility of curcumin during digestion. These results may provide valuable references for the design of therapeutic dairy products beneficial to health in terms of food matrix.