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The qualities of beef cuts were compared with near-infrared (NIR) spectroscopy readings using reflectance, transmittance and a fiber optic probe. Multiple linear regression analyses were used to select the optimum wavelengths for estimating beef properties. High multiple correlation coefficients (R) were obtained for Warner-Bratzler shear value (R=0.798-0.826), protein (R=0.822-0.904), moisture (R = 0.895-0.941), fat (R = 0.890-0.965) and energy content (R=0.899-0.961) with each reflectance, transmittance and using the fiber optic probe. Total pigment content also highly correlated with optical densities using transmittance (R=0.946) and the fiber optic probe (R=0.893). NIR with a fiber optic probe is a useful tool for determining physical and chemical characteristics of beef.The objective of our work was to evaluate NIR spectroscopy using reflectance, transmittance and fiber optic modes as a means of determining physical and chemical characteristics of beef important to consumers. MATERIALS & METHODS MaterialsMuscles from eleven Japanese black steers were used in this study. The range of age at slaughter was 22.5-32.4 mo and the range of body weights was 505-681 kg. The following 6 muscles were dissected from the left side of carcasses 48 hr postmortem: semitendinosus, semimembranosus, psoas major, latissimus dorsi, the anterior portion of the longissimus dorsi, supraspinatus. The sample was cut from the center or thickest portion of each muscle and stored for 24 hr at 1°C for subsequent analyses.

Effects of dietary supplementation and postmortem addition of vitamin E on pigment and lipid stability in raw ground beef were examined in this study. Six Holstein steers were fed a control diet for 232 or 252 d and six Holstein steers were supplemented with 1,500 IU of vitamin E per animal daily for 232 or 252 d. Three aliquots of ground beef from each longissimus lumborum were allotted to the following postmortem treatments: no addition (NO), white mineral oil (OIL), and white mineral oil containing sufficient D-alpha-tocopherol to equal the mean difference of alpha-tocopherol concentration between beef from supplemented and control steers (OIL + E). Metmyoglobin percentages and 2-thiobarbituric acid reactive substances values were determined at d 1, 3, 5, 7, and 9 after postmortem treatment. Dietary vitamin E supplementation delayed metmyoglobin increase and highly suppressed lipid oxidation in ground beef during 9 d of display compared with the control. The postmortem addition of vitamin E (OIL + E) was slightly effective in retarding the oxidation of pigment and lipid, especially compared with the OIL treatments. Endogenous vitamin E improved pigment and lipid stability much better than exogenous vitamin E.

The effects of dietary vitamin E supplementation and vitamin C dip treatment on color and lipid stability in longissimus muscle from Holstein and crossbred beef steers were studied during 16 days of display at 4°C. Dietary vitamin E supplementation retarded metmyoglobin formation of the meat and highly suppressed lipid oxidation compared to the control. Holstein longissimus showed higher metmyoglobin formation than crossbred beef longissimus. Dip treatment with a vitamin C solution was effective in maintaining stability of beef color and lipid.