PHYSICAL CHEMICAL AND MICROBIOLOGICAL QUALITY OF GOAT MILKPRODUCED IN DISTRITO FEDERAL

Abstract The goals of this study were to evaluate the physicochemical and microbiological quality of goat milk produced in Distrito Federal, Brazil. The samples were collected as pool (n=40) and whole milk samples (n=10). The physicochemical means observed were: Fat (animals: 3.01% ± 0.679, whole milk: 4.45% ± 1.223); nonfat solids (animals: 9.24% ± 0.651, whole milk: 9.2% ± 0.615); density (animals: 1.033g/mL ± 0.002, whole milk: 1.032g/mL ± 0.002); protein (animals: 3.5% ± 0.551, whole milk: 3.67% ± 0.778); lactose (animals: 5.0% ± 0.035, whole milk: 4.94% ± 0.015); acidity (animals: 18.47°D ± 0.552, whole milk: 18.5°D ± 0.5); pH (animals and whole milk: 6.9 ± 0.098); cryoscopic index (animals:-0,560°H ± 0.010, whole milk -0.558°H ± 0.005). There were no positive samples for antibiotic residues. The mean scores microbiological counts were: aerobic mesophilic 1.2x103 CFU/mL (animals), 7.6x103 CFU/mL (whole milk); total coliforms 1.0 CFU/mL (animals), 1.2x104 CFU/mL (whole milk); Escherichia coli 2.0 CFU/mL (animals); psychrotrophics 1.0x104 CFU/mL (whole milk); acid lactic bacteria 4.7x102 CFU/mL (animals), 7.8x103 CFU/mL (whole milk); yeast and moulds, 1.0 CFU/mL (animals), 4.9x103 CFU/mL (whole milk); Staphylococcus aureus 2.1x102 CFU/mL (animals), 2.8x102 CFU/mL (whole milk). Listeria monocytogenes and Salmonella spp. were not detected in any sample. The results indicate that the goat milk produced in Distrito Federal offers quality and microbiological safety and may be an incentive for the further development of dairy goat.

摘要 本研究旨在评估巴西联邦特区（Distrito Federal）所产山羊乳的理化与微生物学品质。本研究共采集混合样（n=40）与全脂乳样（n=10）两类样本。本次测得的各项理化指标均值如下：脂肪（单体乳样：3.01% ± 0.679，全脂乳样：4.45% ± 1.223）；非脂乳固体（单体乳样：9.24% ± 0.651，全脂乳样：9.2% ± 0.615）；密度（单体乳样：1.033g/mL ± 0.002，全脂乳样：1.032g/mL ± 0.002）；蛋白质（单体乳样：3.5% ± 0.551，全脂乳样：3.67% ± 0.778）；乳糖（单体乳样：5.0% ± 0.035，全脂乳样：4.94% ± 0.015）；酸度（单体乳样：18.47°D ± 0.552，全脂乳样：18.5°D ± 0.5）；pH值（单体乳样与全脂乳样均为6.9 ± 0.098）；冰点指数（单体乳样：-0.560°H ± 0.010，全脂乳样：-0.558°H ± 0.005）。所有样本均未检出抗生素残留阳性结果。微生物计数均值如下：需氧嗜温菌：单体乳样1.2×10³ CFU/mL，全脂乳样7.6×10³ CFU/mL；总大肠菌群：单体乳样1.0 CFU/mL，全脂乳样1.2×10⁴ CFU/mL；大肠埃希氏菌（Escherichia coli）：单体乳样2.0 CFU/mL；嗜冷菌：全脂乳样检出值为1.0×10⁴ CFU/mL；乳酸菌：单体乳样4.7×10² CFU/mL，全脂乳样7.8×10³ CFU/mL；酵母菌与霉菌：单体乳样1.0 CFU/mL，全脂乳样4.9×10³ CFU/mL；金黄色葡萄球菌（Staphylococcus aureus）：单体乳样2.1×10² CFU/mL，全脂乳样2.8×10² CFU/mL。所有样本均未检出单核细胞增生李斯特氏菌（Listeria monocytogenes）与沙门氏菌属（Salmonella spp.）。研究结果表明，巴西联邦特区所产山羊乳具备优良品质与微生物安全性，可为奶山羊养殖业的进一步发展提供积极助力。