Medicine and Health Sciences Commons^™

Evaluation And Improvement Of Coagulation Properties Of Milk For Manufacturing, Leslie M. Okigbo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A rugged and sensitive instrument "Vatimer" was developed to evaluate the coagulation properties of milk in cheese vats. Microvolt signals from the instrument varied with standing-wave motion of milk, forces arising from coagulation, curd firming, curd syneresis and also clean-in-place spray forces. Curd firmness at cutting varied three to four fold in commercial Cheddar cheesemaking operations.

The Formagraph instrument was used to select individual cow milk samples with good and poor chymosin-coagulation characteristics from the Utah State University Holstein herd. Blending 50% good-, and 50% poor-coagulating samples did not improve average coagulation properties of poor samples. Higher chymosin concentration caused …

Survival Of Porcine Pepsin During Cheddar Cheese Making And Its Effect On Casein During Cheese Ripening, Gheyath H. Majeed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A modification of a linear diffusion test for measuring milk clotting enzymes at concentrations of 1 x 10^-4 to 1 x 10^-1 chymosin units/ ml was developed to permit quantitative assay of porcine pepsin in Cheddar cheese with a standard deviation of 6%. The amount of porcine pepsin retained in Cheddar cheese curd was dependent on pH of milk at setting. Milk at pH 6.6, 6.4, 6.2, and 6.0 was set with porcine pepsin, acidified with lactic acid and glucono-~-lactone and made into Cheddar cheese. After pressing the corresponding curd contained 0, 3.64+0 .12 %, 4.79+0.52%, and 5.94+0.30% …

Protein Recovery And Coagulation Properties Of Commercial And Fractionated Milk Clotting Enzymes, Khalida A. Shaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein recovery and coagulation properties of five commercial and fractionated milk clotting enzymes were studied. The fractionated enzymes were Sephadex G-100 fractions of the commercial enzymes. Milk clotting activity of each fraction was tested using Berridge substrate. All fractions from each preparation which had milk clotting activity as measured with the Formagraph were collected and pooled. These samples and the original enzyme preparations were used to coagulate milk. Percent of protein lost in whey was determined by Kjeldahl. Coagulation was followed using a spectrophotometer monitoring changes in apparent absorbance at 600 nm. Curd protein yields using the five original enzyme …