Marination and packaging impact on textural properties of home-frozen broiler breast fillets.

Different packaging is available to consumers, and marination is widely applied. However, their effects on the quality of broiler breast fillets during home freezing are not well known to consumers. Therefore, the objective of this study was to evaluate the effect of packaging materials on the quality of chicken breast fillets after 1, 3, and 6 wk storage at -18°C. A total of 256 fillet were randomly placed in tray packs, freezer bags, butcher paper, and nonpackaged controls. Samples were analyzed for raw pH, color, percent moisture content, and TBA reactive substances (TBARS) at d 0 (only nonpackaged controls), wk 1, 3, and 6, and cooked texture and sensory attributes at wk 1 and 6. There were differences (P < 0.05) in pH, color, percent moisture content, and texture among the treatments by wk 6, but no differences (P < 0.05) in TBARS values and the sensory evaluation (tenderness, juiciness, and overall flavor) were seen. Consumers were not able to detect quality differences (P < 0.05) among treatments despite analytical differences. Experiment 2 was conducted to evaluate the effects of marination on the quality of chicken breast fillets after 2 wk of storage in a home freezer (-18°C). A total of 240 fillets were used in the treatments: nonmarinated fresh nonfrozen, nonmarinated frozen, marinated fresh nonfrozen, and marinated frozen. Fillets were vacuum-tumbled in a 10% solution yielding a final concentration of 0.45% sodium tripolyphosphate and 0.65% salt in the meat. Raw samples were evaluated for color, TBARS, and thaw loss. Cooked samples after 2 wk of storage were analyzed for cook loss, texture, moisture, and sensory evaluation (color, juiciness, tenderness, overall flavor, and preference). Both marinated samples showed better (P < 0.05) quality in terms of L* value, TBARS, cook loss, texture, moisture content, and better sensory attributes (except color) than nonmarinated samples. Quality of marinated samples was not negatively affected by home freezing after 2 wk.

Confounding factors in water EMG recordings: an approach to a definitive standard.

This work presents a study on the influence of the aqueous environment on the surface EMG (sEMG) signal recorded in bipolar montage from the abductor pollicis brevis muscle, when only the forearm is immersed in water. Ten men, 30.1+/-4.0 (mean +/- SD) years old, performed ten 2-s 40% MVC isometric contractions of the abductor pollicis brevis muscle in two controlled environments (air and water, at a temperature of 32 degrees C). They were always equipped with electrodes protected with a waterproof adhesive tape. No significant variations (paired Wilcoxon test) due to the environments were observed in the median frequency of the power spectrum (MDF) and in the root mean square (RMS) value of the sEMG signal. These results allow us to assess the methodological criteria to properly record sEMG signals in water and provide the basis to explain different findings obtained by other authors.