Bornhorst, Gail

Current Research Projects

Food Breakdown Classification System (FBCS)

As food matrices are digested, they are subjected to both the physical and chemical environment of the gastrointestinal tract. In the stomach, foods are immersed in gastric secretions, which contain gastric acid as well as enzymes which contribute to the physical and chemical breakdown of the food matrix and components. Additionally, foods are further broken down as a result of peristaltic muscular contractions in the stomach. In an attempt to classify food products using easily available test methods and equipment, we have developed the Food Breakdown Classification System (FBCS) that groups food materials into six classes based on their initial hardness and their rate of softening in simulated gastric conditions.

Increasing Nutrient Bioaccessibility in Fruit and Vegetable Juices as a Result of Processing

The market for fruit and vegetable juices has increased in recent years, with consumers demanding higher quality products with increased nutritional value. It is well-known that processing conditions influence initial juice quality, properties (i.e. viscosity, particle size) and nutritional content. The increased demand for science-based nutritional information calls for greater knowledge of food nutrient bioaccessibility and bioavailability. However, the link between processing, juice properties, and nutrient bioaccessibility and bioavailability is less clear. The objective of this research is to identify processing conditions (thermal treatment & high pressure processing) that increase nutrient bioaccessibility in fruit and vegetable juices, using orange-red beetroot juice and blueberry-grape juice as model systems. The results from this project will allow juice processors to modify processing conditions and/or juice formulation to provide products with higher nutritional quality (i.e. nutrient bioaccessibility) for consumers.

Mixing and Acid Diffusion during Gastric Digestion

The mechanisms of mixing during gastric digestion are not well understood. There are multiple types of mixing phenomena that occur during gastric digestion: (i) solid (food or drug) particles mixing throughout the stomach; (ii) mixing of secretions with the solid phase of the meal.