分别以不同电压欧姆加热（5 V/cm、8 V/cm、11 V/cm）以及水浴加热的方法将羊肉肉糜加热至中心温度95 ℃，用高效液相色谱法（HPLC）测定其中重要滋味物质（游离氨基酸、5’-核苷酸及其降解产物和丁二酸）含量，同时测定水分、粗脂肪、粗蛋白与盐含量等基本指标，并用气相色谱法（GC）测定其在20 d贮藏期内游离脂肪酸的变化情况。结果发现：欧姆加热低中电压（5 V/cm、8 V/cm）组所得样品具有比水浴加热组样品更浓的鲜味，而高电压组（11 V/cm）滋味较淡。欧姆加热对游离脂肪酸产生具有促进作用，且电压越高，促进作用越强。但高电压组贮藏过程中多不饱和脂肪酸氧化作用较强，可能更易产生不愉快气味。综合来看，欧姆加热低中电压组羊肉糜具有较好的滋味与香味，且略优于传统水浴加热。

Ground lamb longissimus dorsi muscles were cooked to a center temperature of 95 ℃, in water bath or using ohmic heating with different voltages (5 V/cm, 8 V/cm and 11 V/cm). Taste-active compounds, including free amino acids, succinic acid, 5′-nucleotides and 5′-nucleotide degradation products, were evaluated with high-performance liquid chromatography (HPLC). Chemical components including moisture, protein, crude fat, and sodium chloride were also measured, and the free fatty acid changes during the 20-day storage were evaluated with gas chromatography (GC). The results showed that the samples treated with the low- and medium- voltage (5 V/cm and 8 V/cm) ohmic heating had stronger umami taste than those prepared in the water bath, but the sample treated with high-voltage (11 V/cm) heating had fewer taste-active compounds. Ohmic heating promoted free fatty acid production in a voltage-dependent manner. In the samples treated with high-voltage heating, the oxidation of polyunsaturated fatty acids in meat was strong during the storage, which may have led to the formation of unpleasant aroma. In summary, the samples treated with low- and medium-voltage ohmic heating showed relatively good flavor characteristics, which were slightly better than those prepared in the water bath.

国家自然科学基金资助项目（31271894）