Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Emulsion-type sausages were manufactured for evaluation of microstructure, smokehouse yield, and textural characteristics with different lean sources, salt levels, casing sizes and endpoint cooking temperatures. Emulsion stability and water binding capacity of raw batters manufactured with 1, 2 or 3% salt were examined at chopping temperatures of 10, 15.5 and 21$\sp\circ$C. Frankfurters, manufactured with three sources of pork fat, were examined during a nine week storage for oxidative rancidity under different packaging conditions. Bologna from forage-finished beef had lower water, fat and total losses and a higher smokehouse yield than bologna from grain-fed beef at 1 and 2% salt levels. Emulsions with 1 or 2% salt had lower emulsion stability and water binding capacity, lower smokehouse yield and a softer texture than emulsions with 3% salt. Less denaturation occurred in 13.6 cm casings than in 9.6 cm casings. The endpoint cooking temperatures of 74$\sp\circ$C reduced smokehouse yield in low salt treatments compared to 67$\sp\circ$C temperatures. SEM micrographs indicated that bologna with higher salt contents had a thicker protein coating around the fat globule and a more stable emulsion compared to lower salt treatments. A desiccator drying technique after chemical fixation of bologna samples for SEM was judged to be equal to the commonly used critical point drying technique. Cryofracturing without fixation was not satisfactory in allowing specific identification of fat and protein components in bologna specimens. Greater oxidative stability of frankfurters was obtained with vacuum packaging during extended storage times. Frankfurters manufactured with prerigor (warm) fat had lower TBA numbers compared to postrigor (chilled) fat and lard treatments.