利用气相色谱质谱联用和高效液相色谱法检测分析了卤猪肉加工过程中游离脂肪酸、游离氨基酸及核苷酸的变化。结果表明，在加工过程中，总游离脂肪酸有效峰面积呈下降趋势，饱和脂肪酸也呈现下降的变化趋势，不饱和脂肪酸含量先增加后减少，在高温煮制1 h时达到最大值。总游离氨基酸的含量在卤猪肉加工过程中变化明显，在原料肉中总游离氨基酸含量为244.39 mg/100 g，其它样品中含量都显著（p<0.05）高于原料肉，在二次煮制完成后达到最大值，为349.32 mg/100 g。谷氨酸在成品中的含量达到119.02 mg/100 g，占总游离氨基酸的34.12%。呈味核苷酸检测结果显示，在加工过程中5'-IMP和5'-GMP的含量呈现下降趋势。由于加热导致核苷酸热降解，其降解产物肌苷的含量呈现上升趋势，在成品中检测到其含量显著（p<0.05）高于原料肉中的含量。本研究结果为改进卤猪肉的生产工艺、提高产品品质提供了理论参考。

The changes in free fatty acids, free amino acids, and nucleotides during the process of stewed pork were investigated by gas chromatography mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC). The results showed that during processing, the effective peak area of the total free fatty acids showed a downward tendency; the saturated fatty acids also exhibited a decreasing tendency. The unsaturated fatty acid content was increased at first and subsequently decreased, and the content increased to the maximum value when the raw meat was cooked at a high temperature for one hour. The content of total free amino acids underwent significant changes during processing. The content of total free amino acids was 244.39 mg/100 g in the raw meat, and the content in samples from other processing stages were significantly higher (p < 0.05) than those in raw meat. The content increased to the maximum value (349.32 mg/100 g) at the end of the secondary cooking stage. The glutamic acid content was 119.02 mg/100 g in the finished product, accounting for 34.12% of the total free amino acids. The results from measuring flavor nucleotides showed that the content of 5'-IMP and 5'-GMP showed a downward trend during processing. Due to the thermal degradation of nucleotides, the content of inosine, the degradation product, showed an upward tendency, and the content of inosine in the finished product was significantly higher (p < 0.05) than that in raw meat. The results from the present study provide a theoretical reference to optimize the processing techniques of preparing stewed pork and improve product quality.

“十二五”国家科技支撑计划项目（2014BAD04B11）；山东省自然科学基金（ZR2014CL036）；山东省高等学校科技计划项目（J13LF01）