Impact of Chilling Rate on the Evolution of Volatile and Non-Volatile Compounds in Raw Lamb Meat during Refrigeration

The aim of this study was to investigate the effect of chilling rate (1.44, 22.2, and 32.4 °C/h) on the evolution of volatile and non-volatile compounds in raw lamb meat during refrigeration (1, 24, 72, and 120 h). Through orthogonal projection to latent structure-discriminant analysis, the calculation of odor activity values (OAV > 1) and taste activity values (TAV > 1) analysis, 1-octen-3-ol, (E, E)-2,4-decadienal, nonanal, hexanal, nona-3,5-dien-2-one, 2,3-octanedione, hexanoic acid, 1-nonen-4-ol, aspartate (Asp), Glutamic Acid (Glu), 5'-GMP, 5'-IMP, and 5'-AMP were regarded as differential flavor or taste compounds for raw meat undergone different chilling rates. With a rapid chilling rate at 24 h after slaughter, the contribution of 1-octen-3-ol decreased, but (E, E)-2,4-decadienal increased. Moreover, at 24 h post-mortem, the equivalent umami concentration of Asp, Glu, 5'-GMP, 5'-IMP and 5'-AMP in raw meat were significantly lower at a chilling rate of 1.44 °C/h than 32.4 °C/h (p < 0.05). Conclusively, under the rapid chilling rate, more fatty odor and umami compounds accumulated in 24 h aged meat.