Comparison of mineral and cholesterol composition of different commercial goat milk products manufactured in USA.
Concentrations of 12 major and trace minerals and cholesterol in commercial goat fluid milk, evaporated, powdered, yogurt, and cheese products manufactured in the US were evaluated for compositional differences. Minerals were determined by an Inductively Coupled Argon Plasma Emission Spectroscopy (ICAP), while cholesterol was analyzed using colorimetric and gas chromatographic (GC) methods. Mean total solids content (%) of fluid milk, evaporated milk, powdered milk, yogurt, plain soft and Monterey Jack cheeses were: 11.3, 20.9, 94.1, 11.5, 32.5, and 57.7, respectively. Mean calcium and phosphorus contents (ppm, dry basis) of the corresponding products were: 103, 125; 440, 393; 7715, 7471; 161, 144; 691, 1105; 3492, 3067, respectively. The respective iron and zinc contents (ppm) of the corresponding products were: 0.062, 0.349; 1.518, 1.635; 3.33, 30.21, 0.117, 0.338; 7.16, 3.64; 8.86, 3.81. The levels of potassium (K) in cheeses were lowest among all the products including fluid goat milk, suggesting that a significant amount of K was lost during cheese manufacturing processes. Levels of all trace minerals were higher in yogurt and cheeses than in fluid milk. The levels of trace minerals in cheeses were greater than those in yogurt products. Iron and aluminum contents of certain goat milk products were considerably higher than normal, possibly due to contamination of minerals from manufacturing utensils and product metal cans. Sulphur contents of fermented products were significantly greater than those of fluid milk, which may be accountable for the microbial synthesis of sulfur containing proteins during the manufacturing processes of the products. Cholesterol contents (mg/100g, wet basis) of fluid, evaporated, powdered goat milk and Monterey Jack cheese determined by GC method were: 11.0, 24.9, 119.5 and 91.7, respectively. Cholesterol contents of the goat milk products analyzed by colorimetric method were substantially greater than those by GC method.
Park
YW
Georgia Small Ruminant Research and Extension Center, College of Agriculture, Home Economics and Allied Programs, Fort Valley State University, 31030-4313, Fort Valley, GA, USA