To investigate the effects of different culture modes on the volatile flavor composition of Procambarus clarkii, headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to analyze the volatile substances in the meat of Procambarus clarkii from six representative culture modes (from four classes) in Xinghua, Jiangsu Province, and the volatile flavor composition data were evaluated by principal component analysis (PCA) and cluster analysis (CA). A total of 31 volatile substances including eight ketones, three esters, 13 hydrocarbons, three amines, two alcohols, and two other compounds were detected in the meat of Procambarus clarkii. Three principal components were selected for PCA, which had a cumulative contribution rate of 96.01% and represented the main information of the volatile flavor substances. Comprehensive analysis showed that the rice–crayfish co-culture mode (DX1) had the highest score and the lotus–crayfish co-culture mode (OX) had the lowest score. CA classified the six culture modes into five categories and classified all volatile flavor substances detected into four categories, reflecting the differences in volatile components in the meat of Procambarus clarkii from different culture modes. The results were in good agreement with those of PCA for rice-crayfish culture modes.

The present study used principal component analysis (PCA) and cluster analysis to comprehensively investigate the effect of yellow-feathered broilers with different growth rates, namely slow-growing, medium-growing, fast-growing and spent broiler breeders, on quality of chicken broths. To this end, the yield, dry matter content, soluble solid content, turbidity, sodium content, free amino acids (FAA) contents and flavor nucleotide contents of chicken broths from different broiler breeds were compared. Results showed that slow-growing yellow-feathered broiler broth had significantly higher sodium content, turbidity, dry matter content and soluble solid content (P < 0.05) and lower yield than broths from the other breeds. Analysis of flavor substances revealed that fast-growing yellow-feathered broiler broth had significantly higher total FAA content (P < 0.05) with taste activity value (TAV) greater than 1 for glutamic acid (Glu) and histidine (His) as the main flavor contributors; slow-growing yellow-feathered broiler broth contained significantly higher total amount of flavor nucleotide contents (P < 0.05) with TAV greater than 1 for inosine 5’-monophosphate (IMP) as the major flavor nucleotide.Fast-growing yellow-feathered broiler broth had the highest equivalent umami concentration (EUC), indicating the strongest umami taste. A comprehensive evaluation model for chicken broth quality was established by PCA as follows: Y = (0.6224Y₁ + 0.25589Y₂)/0.87829 and was verified by cluster analysis. Fast-growing yellow-feathered broiler broth was found to have the best comprehensive quality. In conclusion, fast-growing yellow-feathered broilers were most suitable for making chicken broth, followed by medium-growing and slow-growing yellow-feathered broilers, and spent broiler breeders were least suitable for making chicken broth.

The aim of this study was to investigate the effect of different content of sodium chloride (NaCl) on lipid oxidation of chicken breast meat and the endogenous pro-oxidants/antioxidants contributing to lipid oxidation. The results demonstrated that NaCl could promote lipid oxidation in chicken meat until NaCl content reached up to 4.5%. Generation of reactive oxygen species and H₂O₂ initiated by NaCl might be responsible for the increased lipid oxidation, and lipoxygenase activity was highly correlated with oxidative stability of meat. However, oxidation of lipid was not negatively correlated with superoxide dismutase, glutathione peroxidase and catalase activity. The sensory evaluation by electronic nose showed an increase in saltiness, richness and umami taste and a decrease in bitterness with increasing NaCl content, but there was no significant change in these sensory ratings when the NaCl content exceeded 3.0%. The volatile compounds obtained by gas chromatography-mass spectrometry (GC-MS) showed that NaCl increased the formation of most flavor components in chicken meat. This study could provide a reference for the control of lipid oxidation in meat and development of low salt meat products.