Evaluation of 20 Macro and Trace Mineral Concentrations in Commercial Goat Milk Yogurt and Its Cow Milk Counterpart

Abstract

Concentrations of 20 different minerals in commercial goat milk yogurt (CGY) and its cow milk yogurt (CCY) counterpart were evaluated in reference to goat milk yogurt manufactured from Fort Valley State University (FVGY), Fort Valley, GA, USA. Three different lots of CGY and CCY each were purchased from local retail stores at Warner Robins, GA, and 3 batches of FVGY were made using goat milk from the University milking herd. All 3 types of experimental yogurts were stored at 4 ° C refrigerator for 4 weeks. Twenty major and trace minerals were analyzed by an Inductively Coupled Plasma Optical Emissions Spectrometer (Thermo Jarrel Ash Enviro 36, Worchester, MA), using argon as the carrier gas and the EPA method 6010. Total solids (TS) content (%) of FVGY, CGY and CCY products were 11.03, 13.1 and 11.3, respectively, indicating CGY had higher TS than the CCY and FVGY yogurt. Respective mean mineral concentrations (ppm, wet basis) of FVGY, CGY and CCY were: Ca 1057, 1162, 1160; P 838, 974, 929; K 1327, 1717, 1208; Mg 102, 133, 113; Na 545, 449, 475; Fe 4.28, 3.33, 2.11; Mn 0.24, 0.19, 0.13; Cu 10.5, 9.85, 7.22; Zn 17.5, 11.7, 11.8. Levels of all macro minerals except potassium were higher in commercial goat and cow yogurts than FVGY, which may be due to the higher TS contents. FVGY had higher Fe, Mn, Cu and Zn than both commercial products. The heavy metal (Pb, Cd and Ni) contents (ppm) appeared to be normal range, while Al contents of FVGY, CGY and CCY were 11.9, 8.66 and 7.65, respectively, which were higher than those of Pb, Cd and Ni. Both commercial products contained higher major mineral contents than the university yogurt, which might be attributable to the differences in diet, breed, and stage of lactation of milking animals, as well as the tapioca additive used in the commercial products.