Analysis And Evaluation Of Main Functional Fatty Acids In Cow Milk, Goat Milk And Human Milk

Milk, a nearly perfect food in the nature, plays a special status and role in human diet and shows crucial importance for human health. Meanwhile, cream, as one of the three nutrients, is the main supply source of calories and nutrients for human body. The contents and species of essential fatty acids in milk fat are quite abundant with a variety of fat-soluble vitamins and digestion rate of 95%, which is a high quality oil resources. At present, there is lack of systematic and relevant researches based on the changing laws of ARA, EPA, DHA content in goat and breast milk colostrum with the variation of lactation stage. In this study,the difference of ARA, EPA, DHA in cattle, goat and breast milk and the difference of ARA,EPA, DHA in different parities of goat milk have been studied firstly. Furthermore, the transformation law of ARA, EPA, DHA in 1-7d goat colostrum and 1-7d colostrum and breast milk have been further studied in detail. The main conclusions in this research can be listed as follow:1) From the GC-MS analysis: the contents of ARA, EPA and DHA in breast milk are(5.67 ± 0.02),(0.36 ± 0.05),(3.10 ± 0.01) mg / g; the contents of ARA, EPA and DHA in goat milk are(1.18 ± 0.07),(0.14 ± 0.03),(0.15 ± 0.01) mg / g; the contents of ARA and EPA in cow’s milk are(1.37 ± 0.03),(0.13 ± 0.02) mg / g without any DHA in it. Thereby it can be determined that the contents of ARA, EPA and DHA must be strengthen in the recipe during processing infant formula powder whether using goat milk or cow milk as base materials. In contrast, goat milk is better than cow milk.2) Based on the analysis of ARA, EPA and DHA in different parities of goat milk under the same rearing conditions, it demonstrates that there is no significant influence(P> 0.05) for different fetal times on the contents of three kinds of essential fatty acids.3) From the testing of ARA, EPA and DHA in 1-7d goat colostrum, the results show that the content of this three types of functional fatty acid significantly decreased(P <0.05) with the increasing of the number of lactation days. Wherein, the ARA content can be up to(19.14± 0.03) mg / g in the first day and minimum of it is(2.46 ± 0.04) mg / g in the 7 days. For EPA, the highest content is 1(0.84 ± 0.05) mg / g in the first day and the lowest one is(0.23 ±0.03) mg / g after 7 days. Similarly for DHA, the maximum content in the first day and theminimum content in the 5 days are(1.24 ± 0.04) and(0.43 ± 0.04) mg / g, respectively, which out of detection limit after the fifth day.4) From the testing of ARA, EPA and DHA in 1-7d breast milk colostrum, the results show that the content of this three types of functional fatty acid significantly decreased(P<0.05) with the increasing of the number of lactation days. Wherein, the ARA content can be up to(29.62±0.08) mg / g in the first day and minimum of it is(5.67±0.05) mg / g in the 7days. For EPA, the highest content is 1(7.35±0.02) mg / g in the first day and the lowest one is(0.36±0.01) mg / g after 7 days. Similarly for DHA, the maximum content in the first day and the minimum content in the 7 days are(8.60±0.02) and(2.26±0.08) mg / g, respectively.5) Six functional oil-related indicators of three major commercial brands are determined based on the “edible vegetable oil health standards”(GB2716-2005) for evaluation. The related indicators of as-tested grease are almost qualified, however, there are still some differences. In conclusion, Brand A indicates the best quality from a comprehensive comparison.