Department of Dairy Technology, University of Veterinary and Animal Sciences, Lahore, Punjab, Pakistan.
Institute of Home and Food Sciences, Faculty of Life Sciences, Government College University, Faisalabad, Punjab, Pakistan.
Lipids Health Dis. 2019 Mar 9;18(1):59. doi: 10.1186/s12944-019-0995-6.
Among the dietary lipids, milk fat is most complicated as it contains more than one hundred types of fatty acids and several triglycerides. Huge versatility in triglyceride and fatty composition makes it possible to convert milk fat into various fractions on the basis of melting characteristics. Functional properties of milk fat can be increased by converting it into different fractions. After cow milk, buffalo milk is the second largest source of milk and chemical characteristics of buffalo milk fat has been studied in a limited fashion. The main mandate was determination of triglyceride, fatty acid profile and antioxidant characteristics of low melting point fractions of buffalo milk fat for increased industrial applications.
Buffalo milk fat (cream) was fractionated at three different temperatures i.e. 25, 15 and 10 °C by dry fractionation technique and packaged in 250 ml amber glass bottles and stored at ambient temperature for 90 days. The fraction of milk fat harvested at 25, 15 and 10 °C were declared as LMPF-25, LMPF-15 and LMPF-10. Unmodified milk fat was used as control (PBMF). Low melting point fractions were analyzed for triglyceride composition, fatty acid profile, total phenolic contents, DPPH free radicals scavenging activity, reducing power, free fatty acids, peroxide value, iodine value and conjugated dienes at 0, 45 and 90 days of storage.
In LMPF-10, concentrations of C, C, C, and C were 2.58, 3.68, 6.49 and 3.85% lower than PBMF. In LMPF-25, concentrations of C, C, C, C, C and C were 0.71, 1.15, 2.53, 4.8, 0.39 and 2.39% higher than PBMF. In LMPF-15, concentrations of C, C, C, C, C and C were 2.45, 4.2, 3.47, 5.92, 2.38 and 3.16% higher than PBMF. In LMPF-10, concentrations of C, C, C, C, C and C were 2.8, 5.6, 5.37, 7.81, 3.81 and 4.45% higher than PBMF. LMPF-25, LMPF-15 and LMPF-10 had higher concentration of unsaturated fatty acids as compared PBMF. Total phenolic contents of buffalo milk fat and its fractions were in the order of LMPF-10 > LMPF-15, LMPF-25 > PBMF. Storage period of 45 days had a non-significant effect on total flavonoid content. 2, 2-Diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH) free radical scavenging activity of LMP-25, LMPF-15 and LMPF-10 were 4.8, 13.11 and 25.79% higher than PBMF. Reducing power of PBMF, LMPF-25, LMPF-15 and LMPF-10 were 22.81, 28.47, 37.51 and 48.14, respectively. Estimation of free fatty acids after the 90 days of storage duration, no significant difference was found in content of free fatty acids in unmodified milk fat and low melting point fractions. Testing of peroxide value in 90 days old samples showed that peroxide value of PBMF, LMPF-25, LMPF-15 and LMPF-10 was 0.54, 0.98, 1.46 and 2.22 (MeqO/kg), respectively. Storage period up to 45 days had a non-significant effect on anisidine value, iodine value and conjugated dienes.
Low melting point fractions of buffalo milk fat had higher concentration of unsaturated fatty acids and more antioxidant capacity than unmodified milk fat with reasonable storage stability.
在膳食脂质中，牛奶脂肪是最复杂的，因为它含有一百多种脂肪酸和几种甘油三酯。由于甘油三酯和脂肪酸组成的巨大多样性，有可能根据熔化特性将牛奶脂肪转化为各种馏分。通过转化为不同的馏分，可以提高牛奶脂肪的功能特性。在牛奶之后，水牛奶是第二大水牛奶源，并且已经对水牛牛奶脂肪的化学特性进行了有限的研究。主要任务是确定低熔点分数的水牛牛奶脂肪的甘油三酯、脂肪酸谱和抗氧化特性，以增加工业应用。
通过干法分馏技术，在 25、15 和 10°C 三个不同温度下对水牛牛奶脂肪（奶油）进行分馏，并将其包装在 250ml 琥珀色玻璃瓶中，在室温下储存 90 天。在 25、15 和 10°C 下收获的乳脂馏分分别被宣布为 LMPF-25、LMPF-15 和 LMPF-10。未改性牛奶脂肪用作对照（PBMF）。在储存 0、45 和 90 天的时间内，对低熔点分数进行甘油三酯组成、脂肪酸谱、总酚含量、DPPH 自由基清除活性、还原能力、游离脂肪酸、过氧化物值、碘值和共轭二烯的分析。
在 LMPF-10 中，C、C、C 和 C 的浓度比 PBMF 低 2.58%、3.68%、6.49%和 3.85%。在 LMPF-25 中，C、C、C、C、C 和 C 的浓度比 PBMF 高 0.71%、1.15%、2.53%、4.8%、0.39%和 2.39%。在 LMPF-15 中，C、C、C、C、C 和 C 的浓度比 PBMF 高 2.45%、4.2%、3.47%、5.92%、2.38%和 3.16%。在 LMPF-10 中，C、C、C、C、C 和 C 的浓度比 PBMF 高 2.8%、5.6%、5.37%、7.81%、3.81%和 4.45%。LMPF-25、LMPF-15 和 LMPF-10 的不饱和脂肪酸浓度高于 PBMF。水牛牛奶脂肪及其馏分的总酚含量顺序为 LMPF-10> LMPF-15、LMPF-25>PBMF。45 天的储存期对总黄酮含量没有显著影响。LMP-25、LMPF-15 和 LMPF-10 的 2,2-二苯基-1-苦基肼自由基清除活性（DPPH）自由基清除活性分别比 PBMF 高 4.8%、13.11%和 25.79%。PBMF、LMPF-25、LMPF-15 和 LMPF-10 的还原能力分别为 22.81、28.47、37.51 和 48.14。在 90 天的储存期后，估计游离脂肪酸的含量，未改性牛奶脂肪和低熔点分数中的游离脂肪酸含量没有显著差异。在 90 天的样品中测试过氧化物值，结果表明 PBMF、LMPF-25、LMPF-15 和 LMPF-10 的过氧化物值分别为 0.54、0.98、1.46 和 2.22（MeqO/kg）。在 45 天的储存期内，对茴香胺值、碘值和共轭二烯没有显著影响。
与未改性牛奶脂肪相比，水牛牛奶脂肪的低熔点分数具有更高的不饱和脂肪酸浓度和更高的抗氧化能力，并且具有合理的储存稳定性。
