Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Nutrition, Dietetics, and Food Sciences

Committee Chair(s)

Prateek Sharma


Prateek Sharma


Robert Ward


Eric Bastian


In this research, we focused on understanding the critical elements impacting consumer experience and the nutritional value of dairy products, specifically their texture, mouthfeel, and protein breakdown in the gastrointestinal tract. Our study aimed to accomplish two main goals. First, we performed analysis of the tribological attributes of various commercially dairy products. The second objective was to investigate the process of disintegration and protein release in selected dairy products.

The study included an assessment of eight dairy products of varied consistencies: solid like cheddar, cheese curd, and parmesan; semi-solid such as cottage cheese, ricotta cheese, and yogurt; and liquid represented by milk and whey protein beverage. To achieve our objectives, we used variety of techniques like tribology, particle size examination, and SDS PAGE. We measured the samples' mouthfeel via tribology. Furthermore, we examined the particle size distribution, a significant factor affecting mouthfeel.

The findings indicate differences among the samples based on the Stribeck curve at various sliding speeds. Liquid dairy products displayed considerably higher friction (p < 0.05) compared to semi-solid and solid dairy items, likely due to their unique food structures, protein levels, and moisture content.

The second phase involved the in-vitro digestion of three structurally distinct dairy products using the INFOGEST protocol. The purpose was to understand the process of disintegration and protein release during the gastric and intestinal phases at specific time intervals. The outcomes highlighted the differences among liquid, semi-solid, and solid samples at different stages of the in-vitro digestion process (G0, G15, G30, G60, I5, I30, I60, I120, I180). For instance, liquid dairy items, such as milk, displayed a significantly quicker release of soluble protein compounds during the gastric phase when compared to solid dairy products like cheddar cheese. These varied protein degradation rates were primarily due to the differences in protein content and food structure.

By examining the tribological properties and in-vitro digestibility of dairy products, this study offers valuable insights into the mechanics of texture, mouthfeel, and protein release. The findings of this research can help food industry professionals develop innovative dairy products, augment their nutritional worth, and boost consumer satisfaction.