2023-12-052023-12-052023-05https://hdl.handle.net/2346/97042Grain-finished mature cull cows are a sustainable option for cattle producers and beef packers to meet the high demand of consumers for safe, wholesome, and high-quality red meat protein. Tenderness, flavor, and juiciness are the three key components associated with palatability, and research has been conducted to better evaluate and accentuate these traits in beef. Rapid evaporative ionization mass spectrometry (REIMS) is an innovative form of ambient ionization mass spectrometry, which can identify multiple complex traits from a single measurement when paired with chemometrics (Zhai et al., 2022). The objective of this study was to evaluate the influence of physiological age maturity on sensory attributes varying in degree of marbling and evaluate REIMS capability of differentiating beef based upon physiological age, quality grade, and consumer acceptability. Grain-finished beef carcasses were selected from two maturity groups: old maturity beef (O; n=448) and young maturity beef (Y; n=423). Old maturity beef carcasses were determined to be over thirty months of age (through dentition and skeletal maturity). Within skeletal maturity groups, carcasses were selected to represent five marbling degrees: Slightly Abundant or greater (SLAB) (O; n = 89) (Y; n = 85), Moderate (MD) (O; n = 90) (Y; n = 84), Modest (MT) (O; n = 91) (Y; n = 84), Small (SM) (O; n = 88) (Y; n = 85), and Slight (SL) (O; n = 90) (Y; n = 85). Longissimus dorsi samples measuring ~10 cm. were removed from each selected carcass on day two postmortem and equally divided into three ~3 cm. steaks for slice shear force (SSF), consumer sensory panels, proximate analysis, REIMS, and collagen analysis. Consumer panelists in Lubbock, TX (n =320) evaluated 10 grilled beef steak samples for palatability traits and acceptability. Aside from consumer acceptability, all variables evaluated were not impacted by the interaction of carcass type x marbling degree. O and Y fed beef carcass steak samples were numerically different, and steak samples with SLAB, MD, MT, SM, and SL marbling degrees were numerically different. SLAB-O beef ribeye steaks evaluated through a consumer sensory panel (n = 99) at a restaurant setting in New Braunfels, TX resulted in consumer acceptability over 97% for tenderness, juiciness, flavor liking, and overall liking. REIMS analysis of raw beef steaks combined with optimized chemometrics could effectively characterize the physiological age and quality grade of beef with an accuracy rate up to 80% (P <0.001).Embargo status: Restricted until 06/2024. To request the author grant access, click on the PDF link to the left.Application/pdfconsumergrain-fedoldyoungbeefRapid Evaporative Ionisation Mass Spectrometry (REIMS)ThesisRestricted until 2024-06.