黄油的烘焙稳定特性及其脂肪酸含量

Oxidative Stability and Fatty Acid Content of Butter in Baking System

为研究不同烘焙条件对黄油氧化稳定性的影响,以起酥油和棕榈油为对照,分析烘焙体系下黄油酸值、过氧化值、p-茴香胺值、全氧化值、生育酚含量及脂肪酸组成变化。结果表明,在不同烘焙条件下黄油具有较好的氧化稳定性。随着加热温度和时间的延长,起酥油与棕榈油的酸值显著增加(P<0.05),黄油的酸值也呈上升趋势,在250℃趋于稳定(1.69 mg/g)。与起酥油和棕榈油相比,加热温度和时间对黄油的过氧化值影响不显著(P<0.05),基本保持在0.8~0.92 meq/kg。起酥油和棕榈油的最大p-茴香胺值(23.5,24.7)均高于黄油(22.8)。全氧化值大小排序为起酥油>棕榈油>黄油。当温度升至250℃时,起酥油和棕榈油生育酚含量损失较多(77%,79%),黄油相比于两者生育酚含量变化相对较少(72%)。3种烘焙油脂多不饱和脂肪酸含量均降低,黄油在180℃时降低最小(0.8%),且均未发现反式脂肪。饱和脂肪酸与不饱和脂肪酸的比例增加时,油脂氧化稳定性降低。

Changes in acid value,peroxide value,p-anisidine value,total oxidation value,tocopherol content and fatty acid composition under different baking conditions of butter were compared with those of lard and palm oil to determine the oxidative stability of butter.The results showed that butter has good oxidative stability under different baking conditions than lard and palm oil.With increasing temperature and time of baking,the acid value of lard and palm oil increased significantly(P<0.05),and the acid value of butter also increased,and stabilized at 250℃(1.69 mg/g);Compared with lard and palm oil,the baking temperature and time had no significant effect on the peroxide value of butter(P<0.05),which remained at 0.8-0.92 meq/kg;The maximum p-animide values of lard and palm oil(23.5 and 24.7)were higher than that of butter(22.8).The total oxidation values of three baking oils were lard>palm oil>butter.When the temperature was 250℃,the tocopherol content of lard and palm oil was more loss(77%,79%),and the tocopherol content of butter was relatively less(72%).The contents of polyunsaturated fatty acids in all three baking oils decreased,that of butter was the lowest at 180℃(0.8%),and no trans fatty acids was found.As the ratio of saturated fatty acids to unsaturated fatty acids increased,the oxidation stability of oils decreased.