New insights into the search of meat quality biomarkers assisted by Orbitrap Tribrid untargeted metabolite analysis and chemometrics

Influence of lipid and metabolite profiles of mitochondrial fraction on pH and color stability of longissimus lumborum muscle with different ultimate beef pH

This study aimed to explore the differences in the lipidome and mitochondrial fraction metabolome of Nellore cattle meat in different ranges of ultimate pH (pHu) normal (≤5.79), intermediate (5.80 to 6.19) and high (≥ 6.20) after 3- and 21-d postmortem. Instrumental color, myoglobin redox state, oxygen consumption, and metmyoglobin-reducing activity were measured during storage. A total of 472 lipids and 22 mitochondrial fraction metabolites were identified. Beef with high pHu showed positive regulation of ceramides involved in apoptosis and negative regulation of lipid classes related to membrane permeability and stability. In addition, lower carnitine content was noted in high-pHu beef than in normal-pHu beef. Acylcarnitines, phosphatidylinositol, and IMP showed upregulation in beef with intermediate pHu, indicating changes mainly related to energy, purine and pyruvate metabolism. Aging time impacted on the lipid content and metabolites involved in different metabolic pathways. These results provided new insights into beef's mitochondrial fraction lipid and metabolic profile with different pHu. In addition, beef with intermediate pHu differs from beef with high pHu due to changes in energy metabolism.

Lipidome and metabolome profiling of longissimus lumborum beef with different ultimate pH and postmortem aging

The objective of this exploratory study was to assess the changes on lipidome and metabolome profiling of Longissimus lumborum bull muscle with different ultimate pH (pHu) and aging periods. The bull muscles classified as normal, intermediate, or high pHu were collected from a Brazilian commercial slaughterhouse, cut into steaks, individually vacuum-packaged, and aged for 3 days (3-d) or 21 days (21-d) at 2 °C. Muscle extracts were analyzed for the profiles of both lipids, by mass spectrometry (via direct flow-injection), and metabolites, by nuclear magnetic resonance, with downstream multivariate data analysis. As major results, pairwise comparisons identified C12:0 and C14:0 acylcarnitines as potential biomarkers of the intermediate pHu-muscle, which are related to lipid catabolism for alternative energy metabolism and indicate less protein breakage postmortem. Interestingly, the concentration of arginine at early postmortem aging (3-d) may influence the previously reported improved tenderness in normal and high pHu-muscles. Moreover, upregulation of fumarate, formate, and acetate with increased pHu muscle at 21-d aging indicate more intense tricarboxylic acid cycle, amino acid degradation, and pyruvate oxidation by reactive oxygen species, respectively. These three compounds (fumarate, formate, and acetate) discriminated statistically the muscle with high pHu at 21-d aging. The normal pHu-muscle showed higher concentrations of glycogenolysis and glycolysis metabolites, including glucose, mannose, and pyruvate. Hence, our results enhance knowledge of postmortem biochemical changes of beef within different pHu groups aged up to 21 days, which is essential to understand the mechanisms underpinning bull meat quality changes.

From sound check to encore: A journey through high-resolution mass spectrometry-based food analyses and metabolomics

This manuscript presents a comprehensive review of high-resolution mass spectrometry in the field of food analysis and metabolomics. We have followed the historical evolution of metabolomics, its associated techniques and technologies, and its increasing role in food science and research. The review provides a critical comparison and synthesis of tentative identification guidelines proposed for over 15 years, offering a condensed resource for researchers in the field. We have also examined a wide range of recent metabolomics studies, showcasing various methodologies and highlighting key findings as a testimony of the versatility of the field and the possibilities it offers. In doing so, we have also carefully provided a compilation of the software tools that may be employed in this type of studies. The manuscript also explores the prospects of high-resolution mass spectrometry and metabolomics in food science. By covering the history, guidelines, applications, and tools of metabolomics, this review attempts to become a comprehensive guide for researchers in a rapidly evolving field.