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Natural actomyosin was isolated from broiler breast and thigh tissues, characterized by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and examined for thermal transitions (Tm) during heat-induced aggregation. Electrophoresis showed some variation in the quantity of each subunit protein present between the tissue actomyosins and, with Amido Black staining, yielded actin to myosin molar ratios of 5.71 and 6.33 for breast and thigh natural actomyosins, respectively. The heat-induced initiation of protein to protein interactions occurred at 30 to 31 C for actomyosin of breast tissue and at 42 to 44 C for actomyosin of thigh tissue. Two distinct thermal transitions were found for each actomyosin. Derivative curves from the plot of differential change in optical density or absorbance (A) as a function of temperature (T) (dA/dT) between 28 C and 70 C showed Tm1 at 49.2 C and Tm2 at 60.2 C for breast actomyosin with corresponding values of Tm at 52.6 C and 57.9 C for thigh actomyosin. The interval between Tm1 and Tm2 (delta Tm) for thigh actomyosin (5.3 C) was less than that of breast actomyosin (11.0 C). This result suggests that less thermal energy is required for aggregation of actomyosin from thigh tissue. The differences in thermal characteristics between the two actomyosins may be related to differences observed in heat-processed products prepared from breast and thigh tissues.

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Color and nitrosoheme pigment stabilities of dry salami packaged in films differing in oxygen transmission rate (OTR) were studied. Product exposed to light for 8 wk had greater (p < 0.05) retention of redness properties (Judd-Hunter +a coordinates, a/b ratios, hue angles (Q and saturation (S) index values) and greater (~~0.05) nitrosoheme pigment stability as the OTR of the packaging film decreased from 90 cc Da/m*/24 hr to 511 cc 0a/m2/24hr. Redness properties and percent nitrosoheme pigment progressively decreased (~~0.05) during light exposure. Significant redness fading occurred in light-exposed product when compared to dark-stored product. Oxygen transmission to the dry salami surface was a major factor in color loss, primarily if light energy was also present.

Moisture content of 8 types of dried sausage products varied from 58.9-26.4%. Fat, ash, protein nitrogen and total acidity values of each type increased as the moisture content decreased Bacterial counts indicated that the majority of the sausages were fermented, containing the same range of lactic acid bacterial counts as found for total plate counts. Sausage pH ranged from a low of 4.42 to 5.58. A classification system of dried sausages based on moisture-to-protein ratio and percent moisture was found by regression analysis to fit a linear plot. The classification system also included descriptive terminology generally used in industry to denote the stage of product dryness.