Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)

First Advisor

Ibrahim, Salam A.


The overall goal of this project is to develop a new technique that could be applied in the food industry to ensure food-grade probiotics that extend the viability longer, express α-galactosidase/ β-galactosidase, and overall to enhance the quality of dairy products. Specific objectives to be accomplished are as follows: 1) to investigate the effect of mushroom extract on growth of 3 bifidobacteria and lactobacillus in vitro; 2) to determine the effect of shiitake mushroom extract on the pH, titratable acidity, viability and α-galactosidase/ β-galactosidase of probiotics in milk during refrigerated storage; 3) to study the impact of mushroom extract on viability and α-galactosidase/β-galactosidase activities of probiotics in yogurt products during refrigerated storage.