婴儿奶粉过氧化值测定方法的研究

论文编号:SP071  论文字数:9503,页数:29

摘 要：至今为止，我国仍没有检测奶粉过氧化值的国标法，而婴儿奶粉中脂肪含量达到27%，其中不饱和脂肪酸占了大半，所以脂肪过氧化值仍是测定奶粉质量的一个重要指标。奶粉中过氧化物的含量很低，所以用油脂滴定法很难准确测定。本论文主要研究内容是奶粉脂肪提取方法的确定和优化，以及应用三种碘量比色法、铁离子法及澳大利亚AS2300-8-6-2004法来测定奶粉中脂肪的过氧化值。实验结果表明超声波萃取法的脂肪提取率可以达到81.89%，且优化后提取率达到92.9%；AS2300-8-6-2004测定方法比较简便且精密度最高（相对偏差为0.18），铁离子法其次，三种碘量比色法的准确性不高且操作过程十分复杂。所以采取超声波萃取法提取脂肪及AS2300-8-6-2004法来测定奶粉中脂肪的过氧化值。
关键词：奶粉；脂肪；过氧化值；测定方法

Abstract: From now on, there is no original method to determinate the peroxide value of dry milk in our country. But the percent of fat in the infant formula is almost 27%, and most of which is unsaturated fatty acid, so the peroxide value is a very important norm to determine whether a kind of dry milk is good. The number of  peroxide in the dry milk is very little, so it’s hard to use the means like oli. This paper studies to choose a good method to take fat from dry milk, and how to determinate the peroxide value of dry milk. There are three methods of iodometry colorimetry. The method of ferric ion and a method based on the mean of determinate the peroxide value of milk fat of Australia. The experiment results show that the ultrasonic method had a 81.89% extraction rate. And the precision of Australia method is best the relative deviation is (0.18), then is the method of ferric ion ,the last is three methods of iodometry colorimnate. So use the ultrasonic method to take fat and the method of AS2300-8-6-2004 to determinate the peroxide value.
 Keywords：infant formula, fat, peroxide value，measuring method

目  录
中文摘要 I
英文摘要 II
目录 III
1. 绪论 1
 1.1 引言 1
 1.2婴儿奶粉中不饱和脂肪酸含量 1 
 1.3婴儿奶粉脂肪氧化机理 2
 1.4测定过氧化值的意义 3
2. 实验部分 4
 2.1实验材料与设备  4
 2.2实验主要试剂 4
 2.3实验方法 5
3. 结果与讨论 8
 3.1脂肪提取的方法 8
 3.2五种检测方法    11
 3.3精密度测定 19
4．总结与展望 23
致谢 24
参考文献 25