MLM型结构脂质特性及氧化稳定性研究

比较研究了菜籽油、菜籽油为底物酶改性制备的含辛酸MLM(中碳链-长碳链-中碳链)型结构脂质的质量指标及其氧化稳定性.含38.1％辛酸的MLM型结构脂质中辛酸96.3％位于甘油sn-1,3位,其游离脂肪酸、皂化值高于菜籽油,氧化稳定性指数(OSI值)、过氧化值(PV)低于原料油脂.添加6种不同抗氧化剂后,结构脂质OSI值有不同幅度的改进,以叔丁基对苯二酚(TBHQ)效果最为显著.添加200 mg/kgTBHQ后MLM型结构脂质的OSI值由5.05 h上升到20.1 h,PV、共轭二烯与硫代巴比妥酸随氧化时间延长而增幅减小.

Characterization and Oxidative Stability of MLM- Type Structured Lipids

Medium-Long-Medium chain (MLM) type structured lipids (SL) of rapeseed oil containing caprylic acids (CA) and rapeseed oil were characterized and their oxidative stabilities were investigated. The SL contained 38.1% CA and 96.3% of the CA incorporated was in position 1 and 3. The free fatty acids and saponification number of the MLM-type SL were higher than that of the rapeseed oil and the oxidative stabilities index (OSI) and peroxide value (PV) of SL was lower than that of canola oil. The OSI of the MLM-type SL was increased after adding six different antioxidants repeactively. tert-butyl hydroxyquinone (TBHQ) exhibited better antioxidant effects than others. The OSI increased from 4.70 h to 20.1h and the growing rate of PV, Conjugeted diene (CD) and thiobarbituric acid (TBA) were lower after adding 200 mg/kg TBHQ.