成型温度对乙基纤维素凝胶化油脂结构和氧化特性的影响  

Effect of Molding Temperature on Structure and Oxidation Characteristicsof Ethyl Cellulose Oleogels

作　　者：戴美娜 罗晶 林荣发 刘祖文 傅红[1] Dai Meina;Luo Jing;Lin Rongfa;Liu Zuwen;Fu Hong(College of Biological Science and Engineering,Fuzhou University,Fuzhou 350108)

机构地区：[1]福州大学生物科学与工程学院,福州350108

出　　处：《中国食品学报》2023年第7期80-87,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金面上项目(31771936)。

摘　　要：研究乙基纤维素(EC)的玻璃化温度(Tg)和熔融温度(Tm)以及冷却方式对其制备凝胶化油脂的力学特性和氧化特性的影响,阐明氢键形成效应与EC凝胶化油脂氧化速率的相关性。结果表明,在EC(黏度40~50 mPa·s)的Tg(135℃)和Tm(187℃)下制备的凝胶化油脂均具有类固体行为。与Tg相比,Tm制备样品的储能模量和硬度等质构特性较高,25℃贮藏30d后的顶空耗氧量为0.71%。偏光显微镜和扫描电镜观察到Tm制备样品中EC能更好地溶解于油相,其油滴孔隙直径为Tg样品的38.56%,凝胶网络结构更加致密。傅里叶红外光谱显示:在Tg和Tm下制备的EC凝胶化油脂的羟基伸缩振动峰分别为3 472.48,3 468.48 cm^(-1),氢键效应增强。当EC添加量从4%增到10%时,顶空耗氧量随之下降,10%EC添加量的缓慢冷却样品的顶空耗氧量仅为快速冷却的64.67%,其羟基伸缩振动峰从快速冷却的3 499.74 cm^(-1)红移至3 471.78 cm^(-1),氢键效应增强。上述结果表明,EC凝胶化油脂制备过程中氢键效应的增强导致液晶网络结构更加致密,降低了油脂的氧化速率。The glass temperature(Tg)and melting temperature(Tm)of ethyl cellulose(EC)and cooling methods of oleogels which effected on the mechanical properties and oxidation characteristics of the gel were studied.Meanwhile,the relationship between hydrogen bonding and oxidative stability of EC oleogels were described.The results showed that the oleogels prepared at the glass temperature(135℃)and melting temperature(187℃)of EC(EC with viscosity of 40~50 mPa·s)all had solid-like behavior.Compared with Tg,the storage modulus and texture properties of samples prepared at Tm were higher.After stored at 25℃for 30 days,the headspace oxygen consumption of the Tm sample was 0.71%.Polarization microscope and scanning electron microscope showed that EC could be better dissolved in the oil phase when oleogels prepared at Tm,and the gel network structure was more compact.The pore diameter of the oil droplets was 38.56%of the Tg.Fourier transform infrared spectroscopy showed that the hydroxyl stretching vibration peaks of EC oleogels prepared at Tg and Tm shifted from 3472.48 cm^(-1) to 3468.48 cm^(-1),which implied the hydrogen bond effect was enhanced.With the addition of EC from 4%to 10%,the headspace oxygen consumption decreased with the increase of the addition of EC.Compared with the fast cooling sample of 10%EC,the headspace oxygen consumption of the slow cooling sample was only 64.67%of it,and the hydroxyl stretching vibration peak shifted from 3499.74 cm^(-1) to 3471.78 cm^(-1) which showed the hydrogen bond effect was enhanced.The results showed that the enhancement of the hydrogen bonding during the preparation of EC oleogels formed a denser liquid crystal network structure and reduced the oxidation rate of the oleogels.

关 键 词：乙基纤维素 凝胶化油脂 玻璃化温度 熔融温度 氢键 

分 类 号：TS221[轻工技术与工程—粮食、油脂及植物蛋白工程]