In vitro gastric digestion and emptying of tsampa under simulated elderly and young adult digestive conditions using a dynamic stomach system

The world population is inevitably aging tremendously, whereas quantitative studies on elderly digestion is scarce. This study quantified in vitro gastric digestion and emptying of a traditional Tibetan diet (tsampa) in the elderly using a dynamic stomach system. The emptying half-time for its solid fraction was 83.1 and 103.4 min under young adult and elderly conditions, respectively. After 180 min digestion, the starch digestibility was 13.7% and 9.7% for the elderly and adult, respectively. However, the total peptides released was 44.9 g/100 g protein under elderly conditions, significantly lower than that in adult digestion (50.7 g/100 g protein). The decreased gastric emptying rate and impaired protein digestion are supported by greater viscosity and denser structure of the digesta during elderly digestion due to the reduced gastric secretions and weaker contractions. The present study is meaningful for development of highland barley-based food products that may be more suitable for the elderly.