Special Seminar: Breakdown and Mixing of Food during Gastric Digestion: Implications for Optimizing Health Benefits from Foods
Special Seminar:
Breakdown and Mixing of Food during Gastric Digestion:
Implications for Optimizing Health Benefits from Foods
Dr. Gail Bornhorst
University of California – Davis
4:00-5:00 p.m., Wednesday, 24 October 2012
Rm 208 Farrall Hall
Abstract: Food breakdown during gastric digestion is a crucial process necessary for absorption of energy and nutrients from ingested foods and drugs, but is still not fully understood. Many previous studies in the medical, pharmaceutical, and nutrition fields have focused on topics such as gastric motility, as well as certain “endpoint measurements”, such as absorption of drugs or glucose into the blood, and rate of gastric emptying. However, the actual breakdown mechanisms that play a key role in these measured endpoints are rarely considered.
In order to understand the breakdown of a solid meal during gastric digestion, we recently studied meals of cooked brown rice, cooked white rice, raw almonds, and roasted almonds. Their physical and chemical breakdown was examined in the proximal and distal regions of pig stomachs as a model for the adult human over an 8-12 hr postprandial period. The rate of mixing of gastric secretions with the meal bolus, as well as the mixing of the solid meal particles, was also measured, and quantitative mixing indices were calculated to determine mixing rate constants.
To optimize functional food design, it is essential to understand how the food physical and chemical properties influence their breakdown in the stomach - a controlling factor in the health and digestive properties of the food product. Relationships must be developed between the level of initial processing of a product, food structure, and food composition with the food breakdown kinetics to fully be able to optimize future food design. These future food products could provide many useful health benefits to consumers, such as longer satiety (useful for weight management), more efficient energy release (crucial for athletes), controlled glucose absorption (vital for diabetics), and optimized drug and/or nutrient release and absorption.
Brief bio: Dr. Gail Bornhorst earned her B.S. in biosystems engineering at MSU and her M.S. and Ph.D. in biological systems engineering at the University of California – Davis, funded by an NSF graduate research fellowship, under the guidance of Dr. R. Paul Singh. In addition to her academic experience at UC Davis, Dr. Bornhorst also was twice a visiting scholar at Massey University in New Zealand, and completed two industry internships (at the Kellogg Company and Nestlé USA).