Variations in the Metabolome of Unaged and Aged Beef from Black-and-White Cows and Heifers by 1H NMR Spectroscopy.

(1) Background: The selection of raw material and the postmortem processing of beef influence its quality, such as taste. In this study, the metabolome of beef from cows and heifers is examined for differences during aging. (2) Methods: Thirty strip loins from eight heifers and seven cows (breed code: 01-SBT) were cut into ten pieces and aged for 0, 7, 14, 21 and 28 days. Samples from the left strip loins were wet-aged in vacuum, while samples from right strip loins were dry-aged at 2 °C and 75% relative humidity. The beef samples were extracted with methanol-chloroform-water, and the polar fraction was used for 1H NMR analysis. (3) Results: The PCA and OPLS-DA showed that the metabolome of cows and heifers varied. Eight metabolites revealed significant differences (p < 0.05) in the samples from cows and heifers. The aging time and aging type of beef also affected the metabolome. Twenty-eight and 12 metabolites differed significantly (p < 0.05) with aging time and aging type, respectively. (4) Conclusions: The variations between cows and heifers and aging time affect the metabolome of beef. By comparison, the influence of aging type is present but less pronounced.

Analysis of aging type- and aging time-related changes in the polar fraction of metabolome of beef by 1H NMR spectroscopy.

The tenderness and taste of beef is improved by either dry- or wet-aging or a combination of both. The objective was to develop a validated method for detecting differences in the polar fraction of metabolome in dry-aged and wet-aged beef over the aging time and quantifying the metabolites of interest by 1H NMR spectroscopy using beef. Sixty strip loin (M. longissimus dorsi) samples aged in different ways (wet-aging vs. dry-aging) and aging times (0, 7, 14, 21, 28 days) were analyzed. The aging type could be defined by linear discriminant analysis with an accuracy of 95%. Ten (lactic acid, alanine, methionine, fumaric acid, inosine, inosine monophosphate, creatine, betaine, carnosine and hypoxanthine) out of eighteen metabolites differ significantly (p < 0.05) in content depending on the aging type. Fifteen metabolites in dry-aged and ten in wet-aged beef correlate with the aging time (r > 0.7, <-0.7), which shows significant aging time-related effects on the polar fraction of metabolome.