对实验所用猪肉的氨基酸组成及脂肪酸组成进行分析.将猪肉清炖3h的肉汤,采用溶剂辅助蒸发提取,气相色谱-质谱联机分析,通过谱库检索和保留指数核对,鉴定出70种化合物;进一步采用稀释法-气相色谱-嗅闻分析,结合保留指数、气味特征及与标准品比对,鉴定出24种香气活性物质.所鉴定的气味活性化合物主要为脂肪族的醛类、酮类、醇类及含硫化合物,稀释因子较高的(log2FD≥9)有庚醛、壬醛、(E)-2-壬烯醛、(E,E)-2,4-癸二烯醛、2-十一酮、3-羟基-2-丁酮、3-(甲硫基)丙醛、糠硫醇、二甲基三硫醚、2-噻吩硫醇、双(2-甲基-3-呋喃基)二硫醚、1-辛烯-3-醇、γ-癸内酯.
The amino acid composition and fatty acid composition of raw pork were analyzed. The pork broth obtained after stewing the pork for 3 h was extracted by solvent assisted flavor evaporation (SAFE), and then analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 70 volatile compounds were tentatively identified from the broth by means of library search in the NIST 2010 mass spectral library through comparison of retention index with those reported in the literature. Out of these compounds, 24 odor-active compounds mainly including aliphatic aldehydes, ketones, alcohols, and sulfur-containing compounds were further screened by gas chromatography-olfactometry coupled with aroma extract dilution analysis (AEDA) through comparison of retention index, mass spectra and odor characteristics with those of the authentic standards. Those with high flavor dilution factors (log2FD 〉 9) were heptanal, nonanal, (E)-2-nonenal, (E,E)-2,4- decadienal, 2-undecanone, 3-hydroxy-2-butanone, 3-(methylthio)propionaldehyde, furfuryl mercaptan, dimethyl trisulfide, 2-thiophenethiol, bis(2-methyl-3-furyl)disulfide, 1-octen-3-ol, and γ-decalactone.