Changes in flavors profiles of stewed bone-in lamb loin during cooking by DHS/GC-MS combined with electronic bionic systems

Abstract

To identify the changes in flavor profiles of bone-in lamb loin during cooking, the volatile flavor compounds, free amino acid, and 5ʹ-nucleotide concentration were evaluated by using dynamic headspace sampling-gas chromatography-mass spectrometry, electronic bionic system, sensory evaluation. The results showed the total concentration of volatile flavor compounds significantly increased with prolonged cooking time. Nonanal, hexanal, heptanal, 1-octen-3-ol, eugenol, eucalyptol, and 3,7-dimethyl-1,6-octadien-3-ol were the key odor compounds. The total free amino acid (TFAA) concentration significantly decreased after heat treatment, but the proportion of umami free amino acids significantly increased with cooking time (P < 0.05). The equivalent umami concentration (EUC) first increased then decreased in 100 °C group (peak at 1.5 h), compared with the continuous increase in 75 °C group. Meanwhile, an analysis of bionic system showed the samples had significant differences in bitterness, astringency, umami, saltiness, and richness. The 5ʹ-nucleotide, and EUC positively correlated with umami and sensory valuation indicators. Bone-in lamb loin heated at 100 °C exhibited higher concentrations of alcohols, aldehydes, esters, heterocycles, and higher taste of bitterness and saltiness, while the 75 °C groups exhibited higher taste of umami at longer heat times. This study provides a theoretical basis for flavor control of bone-in lamb.