不同熬制条件下猪肉汤中滋味成分的变化

Analysis of Non-volatile Flavor Components in Pork Broth with Different Cooking Conditions

通过对不同熬煮条件下猪肉汤中游离氨基酸、核苷酸、肽分子质量分布、维生素B1、嘌呤含量的测定,探究熬煮条件对猪肉汤中营养成分的影响。结果显示,96℃下熬制的肉汤样品中游离氨基酸含量一直呈增加趋势,100℃3 h条件下猪肉汤的游离氨基酸含量达到最大值。核苷酸含量随熬煮时间的增加基本呈先增加后趋于平衡并下降的趋势,96℃熬煮条件下主要呈鲜核苷酸IMP含量高于100℃的,并且96℃通空气条件下主要呈鲜核苷酸的生成和溶出速度快。肽分子质量分布随加热时间的延长从大分子质量向小分子质量转移,趋于稳定后主要集中在3 000～1 000 u。维生素B1含量在96℃通空气和100℃样品中熬煮1.5 h时达到最高,在96℃不通空气的样品中熬煮3 h达到最高,其中96℃通空气样品中的维生素B1含量显著高于其它两个样品。嘌呤含量在3种样品熬煮过程中均未超过嘌呤食品限定量,属于中嘌呤食品,可供除急性期痛风患者外的所有人群健康饮用。上述指标测定表明,相对低温通空气熬煮的肉汤样品的营养成分较好。

To explore the effects of cooking conditions on the nutrients of pork broths, free amino acids, nucleotides, peptide distribution, vitamin B1 and purines were determined by HPLC. The results showed that the content of free amino acids in broth cooked at 96 ℃ has been increasing, and in broth cooked at 100 ℃ reached its maximum value when cooked for 3 h. With cooking time increased, content of nucleotide increased first and then decreased. The broth cooked at 96 ℃ contained more IMP than it cooked at 100 ℃, and IMP dissolved in broth faster in sample cooked at96 ℃ with air blowing. The peptides were degraded from the large molecular weight to small molecular weight when cooking, and mainly concentrated in the 3000-1 000 u when cooked for 3 h. The content of vitamin B1 in broths cooked at 100 ℃ and 96 ℃ with air blowing reached maximum when cooked for 1.5 h. For broth cooked at 96 ℃ without air blowing, it reached maximum when cooked for 3 h. And the broth cooked at 96 ℃ contained more vitamin B1 than others. The content of purines in pork broth cooked by processing methods were medium-purine food, and normally drinking would not be harmful to health. Above all, the broth cooked with air blowing at low temperature may have more nutrients.