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Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Dairy Science

First Advisor

Vikram V. Mistry


Reduced fat Cheddar cheeses, manufactured from pasteurized milk (1.3 7 to 1.38% fat) as control or from the same pasteurized milk supplemented with 5% ultrafiltered sweet buttermilk (UBM) as buttermilk treatment, were used to manufacture reduced fat Process cheese. Sixteen and 8 wk old reduced fat Cheddar cheese in 1: 1 blend and disodium phosphate and trisodium citrate ( 1: 1 blend) at 0.50, 1.25 or 2.00% w/w were used for each cheese treatment. Processing was carried out in an open steam-jacketed kettle with indirect heating to 71 °C for 3 min, cooling to room temperature and storing at 4 to 6°C. There were no differences between treatments (P > 0.05) in moisture (48%) and moisture in non fat substance of the Process cheeses. Because of compositional differences between base cheeses, Process cheeses from the buttermilk treatment had lower fat (P < 0.05) than the controls (14.48 vs. 15.10%) and were therefore harder. Ash and pH were not affected by UBM but increased (P < 0.05) with emulsifying salts level while hardness decreased. At similar emulsifying salts levels Process cheeses from the buttermilk treatment had lower (P < 0.05) free oil than control cheeses. Reduced fat Process cheeses from the buttermilk treatment melted less (P< 0.05) and had higher (P < 0.05) apparent viscosity than the control cheeses. Meltability increased in cheeses from the buttermilk treatment with increasing emulsifying salts up to 1.25%, while it was highest in the controls at 1.25%. The UBM did not influence sensory attributes, while emulsifying salts level only influenced mouthfeel and appearance, both being judged better at 2.00% than at 0 .50% emulsifying salts. Microstructure studies revealed a finer dispersion of fat in reduced fat Process cheeses from the buttermilk treatment at 0.50 and 1.25% emulsifying salts. These differences diminished at 2.00% emulsifying salts. This along with the lower free oil suggest better emulsification of fat in cheeses from the buttermilk treatment. The application of UBM to tailor functionality of reduced fat Process cheese appears to be promising.

Library of Congress Subject Headings

Food -- Fat content


Includes bibliographical references (pages 47-56)



Number of Pages



South Dakota State University


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