The effect of electrical stimulation (100 volts, 5 amps for approx 84-100 set) of beef, lamb and goat carcasses on meat palatability was evaluated. Twenty-nine steers, 14 lambs and 11 goats were slaughtered, split into sides and one side from each carcass was electrically-stimulated immediately before chilling by use of a commercial stunning device. Taste panel evaluation and Warner-Bratzler shear values indicated that longissimus muscle samples from electrically stimulated sides of all three species were significantly more tender than samples from the untreated sides. Tenderness ratings for samples from the legs of lamb and goat carcasses indicated that the differences between treated and control samples were not of the same magnitude as those for samples of the longissimus. Flavor ratings for samples from electrically stimulated sides were significantly higher (P < 0.01) for beef; however, no significant differences were observed between samples from treated and cqntrol sides of lamb and goat carcasses. These data suggest that electrical stimulation can be utilized to improve the tenderness of beef, lamb and goat carcasses.

Rheological properties of heat-induced gels from egg albumen and. bovine plasma proteins were measured using a mechanical loading device. Each protein was tested at 8% protein concentration and heated for 0-120 min at 80°C in an agitating water bath. After heating, the viscosity index, apparent elasticity and initial penetration force of the gels were evaluated. Bovine plasma protein dispersions exhibited a substantially higher viscosity index, apparent elasticity and initial penetration force than egg albumen gels. Bovine plasma proteins produced a gel structure which was strong and elastic. By comparison, heat-induced gels of egg albumen proteins were fragile and somewhat brittle. ~

Changes in rheology during the heating of bovine plasma protein suspensions were examined at temperatures between 50°C and 90°C and for concentrations ranging from 6-12% protein isolate over a 3-hr period. An annular pumping device was used to determine a viscosity index for the suspensions. A model was developed to explain the data. The viscosity index increased exponentially with time at a particular temperature while being linearly dependent upon the concentration. The Arrhenius Equation described the effect of temperature on the rate of change of the viscosity index during heating.

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