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Summary: Shrimp undergo rapid deterioration after death, primarily due to enzyme activity and microbial growth, with freezing serving as its primary preservation method. In this study, shrimp underwent both conventional freezing (CF) and magnetic field‐assisted freezing (MF), and the shrimp meat's metabolites were scrutinised via metabonomic analysis techniques. The results demonstrate that MF treatment effectively preserved umami components like glutamic acid (log2(FC) = 0.37) and inosinic acid (1.02) while inhibiting the accumulation of spoilage‐related metabolites such as inosine (HxR) (−2.51), hypoxanthine (Hx) (−1.43) and uric acid (UA) (−1.24). Moreover, specific compounds, including 3‐methylhistidine, 1,6‐bisphosphate, phosphatidylcholine (PC), phosphatidylethanolamine (PE), HxR, Hx and UA were recognised as potential biomarkers throughout the freezing process. This research offers crucial insights into the intricate molecular mechanisms behind magnetic field‐assisted freezing. [ABSTRACT FROM AUTHOR]

Summary: Free fatty acids (FFAs) and triacylglycerols (TAGs) are the main components of edible vegetable oils. In this work, electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) was employed to characterise the molecular composition of FFAs and TAGs in various vegetable oils, including soybean, rapeseed, corn, sunflower, peanut, linseed and olive oils. Semiquantitative analysis of FFAs and structural analysis of TAGs by MS/MS were further conducted to reveal the differences in the molecular compositions of the various vegetable oils. It was found that each vegetable oil has characteristic fingerprints of FFAs and TAGs. MS/MS measurements showed that the high‐abundance TAGs in each vegetable oil were mainly composed of their abundant FFAs and glycerol. FFA and TAG fingerprints of genetically modified (GM) and nongenetically modified (non‐GM) vegetable oils were similar, exhibiting only subtle differences, as confirmed by principal component analysis (PCA). [ABSTRACT FROM AUTHOR]