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Normally, preslaughter acute heat stress could accelerate postmortem glycolysis and impair chicken breast (pectoralis major muscle) quality. However, previous studies indicated that it might be different when the acute heat stress temperature rises to an extreme range (above 35 °C). Therefore, this study’s objectives were to compare the pH decline, glycolytic enzyme activity, and AMP-activated protein kinase (AMPK) phosphorylation at early postmortem among three extreme acute heat stress temperature settings: a control group (36 °C) and two experimental groups (38 °C and 40 °C). Although the temperature did not affect glycogen phosphorylase a and pyruvate kinase activity, there was a decrease in pH decline rate, phosphofructokinase-1 activity, and phospho-AMPK-α[Thr172] within 4 h postmortem when temperature increased from 36 to 40 °C. Temperature also affected hexokinase activity, with the 36 °C-group having the highest activity. The results of the current study, for the first time, indicated that postmortem metabolic rate in chicken breast muscle could be changed by acute heat stress temperature setting at extreme range.

Grapefruit and lemon were exposed to phytosanitary irradiation doses of 0, 0.4, and 1 kGy, and then electronic-sensing screening of irradiation status and identification of radiation-induced ESR markers were conducted during 20 days storage. Codex standard photostimulated luminescence measurement (PSL(1)) was not a reliable indicator of irradiation status. Electronic tongue and electronic nose, however, showed potential as screening tools for discriminating irradiated fruits from non-irradiated counterparts based on principal component analysis of taste attributes and flavor patterns. Calibrated PSL approach clearly distinguished irradiated from non-irradiated samples based on the PSL ratio (PSL(2)/PSL(1)). Verification of irradiation status by electron spin resonance spectroscopy revealed clear paramagnetic centers from both irradiated fruits samples and ethanol-vacuum drying pretreatment improved radiation-induced ESR signal detection; not prominent enough in 0.4 kGy-irradiated commodities during 20 days of storage. Peel parts of both fruits showed high limonene which proportionally increased with irradiation doses (p

Korean citrus fruits (Jinjihyang and Chunggyun) were treated with electron beam (e-beam) at phytosanitary irradiation doses of 0, 0.4, and 1 kGy, and their irradiation status was screened after storage for 0, 10, and 20 days. Because of the inherent limitations of photo-stimulated luminescence (PSL), the first PSL measurement (PSL1) was not sufficient to distinguish the irradiated samples from the non-irradiated controls. The calibrated PSL approach clearly distinguished the e-beam-irradiated samples from the control based on PSL ratio (PSL2/PSL1): > 10, non-irradiated

Thirty New Zealand White rabbits were fed diets containing 0 (control), 1, 2, 4, or 8 g cholesterol/kg diet for 12 weeks to determine the cholesterol dosageresponse of plasma cholesterol and triglycerides, and the development of atherosclerosis. The concentration of plasma cholesterol increased proportionally with the dietary cholesterol dosage during the first 4 weeks, then remained constant until the 12th week. The plasma triglycerides and TBARS concentrations gradually increased with feeding time when rabbits were fed 2 g dosages. Aortas from rabbits fed a 2 g dosage developed moderate to severe multifocal or diffusive atherosclerotic lesions. Aortas from rabbits fed 4 and 8 g dosages were diffusely affected with massive atherosclerotic lesions, and had severe calcification and Alcian blue-positive foci throughout the media of the aorta. These results indicate that at least 2 g of cholesterol/kg in the diet is needed to generate atherosclerotic lesions in rabbit aortas.

Effects of dietary cholesterol [0 (control), 1, 2, 4, or 8 g cholesterol/kg diet for 12 weeks] on lipid contents and fatty acid compositions in red blood cell (RBC) membranes and plasma of rabbits and pathological changes and lipid oxidation in their livers were determined. Contents of total lipid and unsaturated fatty acids in RBC membrane and plasma of rabbits fed ≥4 and ≥2 g dosages, respectively, were significantly higher (p 2 times higher (p