Off-campus South Dakota State University users: To download campus access theses, please use the following link to log into our proxy server with your South Dakota State University ID and password.

Non-South Dakota State University users: Please talk to your librarian about requesting this thesis through interlibrary loan.

Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Dairy Science

First Advisor

Ashraf Hassan


The objectives of this research were to evaluate the rheological, sensorial, and chemopreventive properties of milk fermented with different exopolysaccharide (EPS) producing lactic cultures. Reconstituted (11 % wt/vol) skim milk was fermented with single strains of BPS-producing and non-producing cultures. Fermentation was terminated at pH 4.64 and fermented milk was stored at 4 °C for 12 hours before use. Whey collected on the surface of undisturbed fermented milk samples and after cutting was measured. All BPS-producing cultures reduced the amount of whey present on the surface of the undisturbed samples while only three out of five strains reduced syneresis measured after cutting. All BPS-producing cultures except a strain of Lactobacillus delbrueckii ssp. bulgaricus reduced viscoelastic moduli in fermented milk. Different BPS-producing cultures render different levels of ropiness in fermented milks. There was a linear correlation between ropiness and viscosity (measured at 250 S-1), and ropiness and smoothness. In the chemoprevention study, 140 male Fisher rats (6 weeks old) were divided into 7 groups of 20 each. Rats in 6 groups were fed diets supplemented with

Library of Congress Subject Headings

Fermented milk
Dairy products
Dairy products -- Rheology
Microbial exopolysaccharides
Cultures (Biology)


Includes bibliographical references (pages 51-66)



Number of Pages



South Dakota State University


In Copyright - Non-Commercial Use Permitted