摘要：本论文以精炼猪脂肪为原料，使用两种不同商业脂肪酶对其进行酶解，得到酶解产物之后，先采用单因素实验研究猪脂的酶解工艺，随后对挥发性产物进行气相色谱-质谱联用（GC-MS）检测，分析其风物质，并同时对游离脂肪酸含量进行探究。其中，以脂解率作为判断标准，依次研究底物浓度、加酶量、pH、酶解温度以及酶解时间对猪脂酶解效果的影响。最终分别确定两种脂肪酶酶解的最佳工艺条件为：一鸣脂肪酶：底物浓度为55%，酶添加量为2.5%，反应时间3h，pH值为7.5，酶解温度为45℃，脂解率为61.63%；诺文信脂肪酶：底物浓度为55%，酶添加量为1.25%，pH值为8，酶解温度为55℃，酶解时间7h，脂解率为87.77%。对两种脂肪酶酶解的猪脂得到的不同的脂解率产物进行GC-MS分析后可得出：SPME-GC-MS共检测出58种挥发性物质，其中醛类物质的含量明显高于其他几类物质，可见醛类是猪脂脂解的主要降解产物，并且对猪肉风的形成起到至关重要的作用。猪脂脂解后，饱和醛类化合物（己醛、庚醛、辛醛、壬醛、癸醛）几乎存在于所有不同脂解率的样品中。随着脂解率增大，样品中产生的挥发性成分含量也增大，而脂解率再增大时，含量反而减少，因此控制脂解率对于最终的风有重要影响。7370
关键词：猪脂；脂肪酶解；风物质；GC-MS
Products and process research of lipolyzed lard
Abstract：Lipase hydrolysis has been investigated using two kinds of commercial lipases and lard as raw material, the products were obtained by optimized the manufacturing parameters. Then the volatile components of the products were analyzed by gas chromatography - mass spectrometry (GC-MS). Meanwhile, the content of free fatty acids of products was analyzed. Firstly, the single factor experiment was designed to study the influence of the substrate concentration, enzymolysis temperature, enzymolysis time, the content of enzyme and pH value on the enzymatic hydrolysis of lard, which was featured by lipolyzed ratio. Finally, the optimum conditions of YIMING lipase were: the lard hydrolyzed at 45○C for 3h with 2.5% lipase in pH7.5. Optional Novo lipase conditions were: the lard hydrolyzed at 55○C for 7h with 1.25% lipase in pH 8. Totally 58 volatile compounds were identified using gas chromatography- mass spectrometry. The result showed that the content of aldehydes more than the other compounds. The aldehydes, which were the main degradation product of lard, played an important role in the forming flavor of lard. A lot of saturate aldehydes ( hexanal, heptanal and nonanal) were present in all of the samples. The content of volatile compounds also increased quickly with the lipolyzed ratio. The result demonstrated the importance of controlling the lipolyzed ratio in forming of the flavor.
KeyWords: lard; lipase hydrolysis; flavor; GC-MS
目 录
1 绪论 1
1.1 肉香精研究概况 1
1.2 猪脂制备猪肉香精的研究概况 1
1.2.1 脂肪酶性质及应用 1
1.2.2 脂质与肉类风的形成 2
1.2.3 Maillard反应的研究概况 2
1.3 游离脂肪酸以及风成分分析与检测 2
1.3.1气相色谱－质谱联用 2
1.3.2 游离脂肪酸成分分析 3
1.4 研究目的和意义 3
1.5 主要研究内容 4
2 实验材料和方法 5
2.1 实验材料 5
2.1.1 原料与试剂 5
2.1.2 仪器与设备 5
2.2 实验方法 6
2.2.1 猪脂酶解工艺 6 脂肪酶水解猪脂产物及工艺研究:http://www.youerw.com/shiping/lunwen_5299.html