Life Sciences Commons^™

Effects Of Bulk Starter Media And Proteolytic Lactic Streptococci On Protein Loss In Cheddar Curd Manufacture, Steven A. Winkel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of whey-based and milk-based starter media, and low concentrations (0.02% each) of citrate, phosphate and calcium upon various milk coagulation properties were measured. Samples inoculated with milk-based starter medium had shorter coagulation times, faster rate of curd formation, and greater final curd firmness than those inoculated with externally neutralized whey-based starter. Starter medium treatment was statistically interacted with calcium for coagulation time and rate of curd formation. Citrate addition caused longer coagulation times, slower rates of curd formation, and weaker final coagula. Citrate interacted with calcium and phosphate for several of the parameters measured. Addition of phosphate did …

Iron Requirement Of Clostridium Botulinum Type A And Characterization Of Iron-Sulfur Proteins In Nitrite Treated And Untreated Botulinal Cells, Divya Shree A. Reddy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of added iron on the growth of Clostridium botulinum type A in a chemically defined medium was studied. Growth of C. botulinum was supported by an iron level of 0.05 ug/ml with maximum growth observed at a level of 3 ug iron/ml.

Electron paramagnetic resonance (EPR) studies were conducted to detect the presence of iron-sulfur centers and iron-nitric oxide complexes in untreated and nitrite treated cell-free extracts of C. botulinum type A. Untreated extracts of C. botulinum exhibited EPR signals in the oxidized and reduced states characteristic of a "HiPiP-type" iron-sulfur center (g=2.02) in the oxidized state and …

Reduction Of Sodium Nitrite And Sodium Chloride In A Cured Meat Product By Using Acid Development To Inhibit Botulinal Toxin Formation, Angsana Assamongkorn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pediococcus acidilactici as a lactic acid producer, and sucrose were added to breakfast strip products in order to reduce added levels of sodium nitrite and sodium chloride and yet limit the growth of Clostridium botulinum and inhibit toxin production. Sucrose at 0.4 or 0.9% with P. acidilactici at 1.0 x 10⁸ cells/g were added during preparation of breakfast strip products prepared with combinations of 40 or 80 ppm sodium nitrite and 1.0 or 2.0% sodium chloride. Other ingredients were added at levels normally used in cured meat products. C. botulinum types A and B at 1,000 spores/g were inoculated …

Modifying Lamb/Mutton Flavors In Processed Meat Products By Smoking, Curing, Spicing, Starter Cultures And Fat Modifications. Investigating The Use Of The Technicon Infraalyzer 400r As A Rapid Method For Proximate Analysis, Chima I. Osuala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mutton meat was tested in different products in order to obtain prototype products in which mutton can effectively be used without the objectionable mutton off flavor. Mutton flavor reduction was achieved in the processed meat products by: (a) lowering mutton fat to a level of 10% or less, (b) using spices, smoking and/or curing, (c) substituting fat from beef or pork for mutton fat, and (d) the action of microbial starter cultures. Four taste panel sessions were set up to rate these products against an all beef or all pork control for consumer acceptability. Taste panel results indicate that flavor …

Effect Of Iron On Residual Nitrite Level In Ground Pork And Model Systems, Changmin Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of iron, temperature, and presence of botulinal spores or sodium ascorbate on depletion of nitrite level were determined in meat and model systems. Higher temperature and presence of botulinal spores definitely increased nitrite depletion in a meat system. Added hemoglobin also significantly increased nitrite depletion, while ferrous iron and ferric iron did not significantly decrease nitrite level in a meat system. High temperature and presence of sodium ascorbate increased nitrite depletion in a model system. Only ferrous iron significantly decreased nitrite level in the absence of ascorbate, while ferric iron, heme iron, and ferritin iron did not decrease …

Effect Of Proteolytic Activity Of Streptococcus Cremoris On Cottage Cheese Yield, Gary W. Stoddard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Using proteinase negative variants of Streptococcus cremoris UC310 or UC320 to manufacture cottage cheese, theoretical yields were increased 1.97% and 1.56% respectively when compared to the theoretical yields of the proteinase positive parents. Yield differences were strain dependent and differences between positive and negative variants were not manifest with strains of UC73 and UC97. It was necessary to produce bulk culture using pH control and to add sufficient nitrogenous stimulant to provide carry-over stimulant into the cheese milk. All cultures examined developed normally even when the bulk medium contained a blend of 5% yeast extract and casein hydrolysate. It was …