摘要
目的:探讨牛乳中反式脂肪酸(TFA)在不同热处理条件下的变化规律,为工艺参数确立提供依据。方法:采用罗兹-哥特里法提取乳中脂肪,经甲酯化反应后进行气相色谱分析,对牛乳中的TFA含量进行分析比较。结果:在85℃条件下,随着加热时间的延长,牛乳中TFA含量呈显著上升趋势(P<0.05);相同时间内在超高温(T>133℃)条件下,提高灭菌温度,牛乳中TFA含量变化不大(P>0.05);延长灭菌时间,TFA含量明显增加(P<0.05)。结论:以减少TFA生成量为主要依据确立的巴氏杀菌工艺参数是:85℃、15s;UHT工艺参数为(137±2)℃、4s。
Objective： To explore the change rule of the TFA during the processing of pure milk under different heat treatments and to provide a theoretical reference for optimal process parameters. Methods： Trans-fatty acids are extracted with ethanol and petroleum ether from milk, and then methyl-esterificated and analyzed by GC. Results： These results showed that TFA contents revealed an increase as the extension of heating time at 85 ℃ （P〈0.05）. The sterilization temperature under UHT （T〉 133℃） condition during the same heating time did not reveal an obvious effect （P〉0.05）. TFA revealed an obvious increase with increasing heating time （P〈0.05）. Conclusion： The process parameters for controlling the content of TFA required heating temperature of 85 ℃ and heating duration of 15, and industrial pasteurization temperature of（137 ± 2） ℃, heating duration of 4 s under the UHT conditions.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2013年第6期102-105,共4页
Food Science
基金
西北农林科技大学人才基金项目(Z111020923)
关键词
牛乳
不同热处理
反式脂肪酸
气相色谱
milk
different heat treatments
trans-fatty acid
gas chromatography
