Digestion of curcumin-fortified yogurt in short/long gastric residence times using a near-real dynamic in vitro human stomach

•Curcumin-fortified yogurt was digested in a dynamic in vitro human stomach (DIVHS).•Gastric emptying and pH were mimicked in DIVHS in short/long gastric residence times.•Enzymatic hydrolysis and dilution effect dominated gastric digesta rheology.•Intestinal release of curcumin depended on the gastric emptying in the two states.•Gastric emptying and secretion governed yogurt proteolysis degree in DIVHS. A dynamic in vitro human stomach (DIVHS), simulating the anatomical structures, peristalsis, and biochemical environments of a real stomach as practically as possible, was applied to mimic the gastric pH and emptying during yogurt digestion in short/long gastric residence times. The influences of peristalsis, dilution, and proteolysis on digesta viscosity were quantified respectively, indicating the dominant role of proteolysis and dilution. After incorporating curcumin-whey protein microparticles with targeted-release formula in yogurt, the peak curcumin release during intestinal digestion reached 43% at 120 min in the short gastric residence time and 16% at 180 min in the long gastric residence time. The change in the maximum curcumin release depended on the gastric emptying kinetics in each residence time. This emptying-kinetics dependence was reflected by the slower microparticle disintegration and proteolysis in the long gastric residence time. The dynamic reproduction of realistic gastric conditions using DIVHS helps revealing controlled release from foods.