Sublethal heating can increase subsequent thermal resistance of bacteria, which may compromise the validity of thermal process validations for slow-roasted meats. Therefore, this research evaluated the accuracy of a traditional log-linear inactivation model, developed via prior laboratory-scale isothermal tests, and a novel path-dependent model accounting for sublethal injury, applied to pilot-scale slow cooking of whole-muscle roasts. Irradiated turkey breasts, beef rounds, and pork loins were inoculated with an eight-serovar Salmonella cocktail via vacuum tumble marination in a salt-phosphate marinade.
View Article and Find Full Text PDFPathogen thermal inactivation models currently available to and used by industry consider only the present state of the product when predicting inactivation rates. However, bacteria subjected to sublethal thermal injury can develop partial protection against lethal temperatures. The objective of this study was to extend the capabilities of a previously published path-dependent Salmonella inactivation model by accounting for longer sublethal heating periods and different substrates and to test this new model against independent data.
View Article and Find Full Text PDFAberrant postmortem Ca(2+)-regulation in the early postmortem period is associated with the occurrence of inferior meat quality in turkeys, described as pale, soft, and exudative (PSE). The objective of the current study was to quantify expression of 4 candidate genes responsible for maintaining Ca(2+) homeostasis in turkey skeletal muscle as a function of heat stress: α and β ryanodine receptors (RYR; Ca(2+)-release channels), the sarco/endoplasmic reticulum Ca(2+)-ATPase 1 (SERCA1), and the sarcoplasmic reticulum, Ca(2+)-storage protein calsequestrin (CASQ1). Two genetic lines of turkeys were used: a growth-selected commercial line and a randombred control line.
View Article and Find Full Text PDFThree poultry chilling methods, namely, water chilling (WC), air chilling (AC), and evaporative air chilling (EAC), were compared to evaluate their effects on broiler breast meat quality and consumer sensory characteristics. A total of 189 birds were processed with 1 of the 3 chilling methods. One-third of the birds were hard scalded (57.
View Article and Find Full Text PDFThis study was conducted to investigate the effects of water chilling (WC), air chilling (AC), and evaporative air chilling (EAC) on the moisture content, processing yield, surface color, and visual appearance of broiler carcasses. For the WC treatment, 1 group of birds was hard scalded and submersed into ice slush, whereas for AC, 1 group of birds was soft scalded and exposed to blowing air (1.0 m/s at 0°C) and for EAC, or 1 group of birds was soft scalded and exposed to blowing air and a cold water spray (every 5 min).
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