Korma Sameh A, Li Li, Wei Wei, Liu Pengzhan, Zhang Xinghe, Bakry Ibrahim A, An Peipei, Abdrabo Khaled A E, Manzoor Muhammad Faisal, Umair Muhammad, Cacciotti Ilaria, Lorenzo José M, Conte-Junior Carlos Adam
School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
Department of Food Science, Faculty of Agriculture, Zagazig University, Zagazig 44519, Egypt.
Biomolecules. 2022 May 22;12(5):730. doi: 10.3390/biom12050730.
Goat milk (GM) is an excellent alternative to cow milk and has recently been used in commercial infant formula preparation due to its superior fat composition. Here, the fatty acid (FA) composition, triacylglycerol (TAG) molecular species, thermal behavior and infrared spectra of extracted milk fat from the milk of the two main breeds of dairy goat bred in China (Guanzhong GM (GZG) and Xinong Saanen GM (XSG)) are investigated. Gas chromatography, Fourier-transform infrared spectroscopy, differential scanning calorimetry and ultra-performance convergence chromatography with quadrupole time-of-flight mass spectrometry are applied. The obtained results evidence significant fat compositional differences based on the breed that produced the considered GM. The major FAs in both GM fats were capric (C10:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0) and oleic (C18:1 n-9c). GZG presented a higher content of medium-chain saturated FAs, while XSG had higher unsaturated FAs with higher ratios of L/Ln and n-6/n-3. A total of 339 and 359 TAGs were detected and quantified in GZG and XSG, and the major TAGs were those of m/z 740.6712 (14.10 ± 0.27%) and m/z 684.6094 (10.94 ± 0.02%), respectively. Milk TAGs of GZG and XSG showed 24-54 and 26-54 total acyl carbon numbers with a 0-4 and 0-5 double bond number at 68 and 72 various retention times, respectively. Thermal analysis showed that all GM fat samples melted below normal body temperature. Infrared spectra revealed higher absorption values of GZG milk fat. This study provides valuable information to the dairy industry sector about GM fat produced in China, assessing the appropriateness of Chinese GM fat to be applied in Chinese infant formula.
山羊奶（GM）是牛奶的优质替代品，由于其优质的脂肪成分，最近已被用于商业婴儿配方奶粉的制备。在此，对中国养殖的两个主要奶山羊品种（关中奶山羊（GZG）和西农萨能奶山羊（XSG））的乳脂肪中的脂肪酸（FA）组成、三酰甘油（TAG）分子种类、热行为和红外光谱进行了研究。应用了气相色谱法、傅里叶变换红外光谱法、差示扫描量热法和超高效收敛色谱-四极杆飞行时间质谱法。所得结果表明，基于所产山羊奶的品种，脂肪组成存在显著差异。两种山羊奶脂肪中的主要脂肪酸为癸酸（C10:0）、肉豆蔻酸（C14:0）、棕榈酸（C16:0）、硬脂酸（C18:0）和油酸（C18:1 n-9c）。GZG的中链饱和脂肪酸含量较高，而XSG的不饱和脂肪酸含量较高，且L/Ln和n-6/n-3的比例更高。在GZG和XSG中分别检测并定量了339种和359种TAG，主要TAG分别为m/z 740.6712（14.10±0.27%）和m/z 684.6094（10.94±0.02%）。GZG和XSG的乳TAG在68和72个不同保留时间下，总酰基碳数分别为24 - 54和26 - 54，双键数分别为0 - 4和0 - 5。热分析表明，所有山羊奶脂肪样品均在正常体温以下熔化。红外光谱显示GZG乳脂肪的吸收值更高。本研究为乳制品行业提供了有关中国产山羊奶脂肪的有价值信息，评估了中国山羊奶脂肪应用于中国婴儿配方奶粉的适宜性。
