Koutsidis G, Elmore J S, Oruna-Concha M J, Campo M M, Wood J D, Mottram D S
Department of Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AP, UK.
Meat Sci. 2008 Jun;79(2):270-7. doi: 10.1016/j.meatsci.2007.09.010. Epub 2007 Sep 26.
Changes in glycolytic metabolites, nucleotide degradation products, free amino acids and other amino compounds were monitored in beef muscle (M. longissimus lumborum), stored for 21days at 4°C, in order to evaluate how post-mortem conditioning may affect flavour formation in beef. The major effects observed in sugar-related substances were the dephosphorylation of the phosphates of glucose, fructose and mannose, to yield their free sugars, as well as the breakdown of inosine 5'-monophosphate, to give a sixfold increase in ribose. Total reducing sugars increased by only 15% during conditioning, while glycogen levels remained unchanged from 2days post-slaughter. Free amino acids increased during conditioning, particularly between days 7 and 14. Phenylalanine, methionine, lysine, leucine and isoleucine were the amino acids showing the greatest increase with conditioning time, with methionine, in particular, showing a sevenfold increase during the conditioning period. The effects of these precursor changes on cooked beef flavour are discussed.
为了评估宰后调理如何影响牛肉风味的形成，对在4°C下储存21天的牛腰大肌中的糖酵解代谢产物、核苷酸降解产物、游离氨基酸和其他含氮化合物的变化进行了监测。在与糖相关的物质中观察到的主要影响是葡萄糖、果糖和甘露糖的磷酸去磷酸化，产生它们的游离糖，以及5'-肌苷酸的分解，使核糖增加了六倍。在调理过程中，总还原糖仅增加了15%，而糖原水平自屠宰后2天起保持不变。游离氨基酸在调理过程中增加，特别是在第7天至第14天之间。苯丙氨酸、蛋氨酸、赖氨酸、亮氨酸和异亮氨酸是随着调理时间增加最多的氨基酸，尤其是蛋氨酸，在调理期间增加了七倍。讨论了这些前体变化对熟牛肉风味的影响。
