Levels of Se, Zn, Mg and Ca in commercial goat and cow milk fermented products: Relationship with their chemical composition and probiotic starter culture Miguel Navarro-Alarcón, Carmen Cabrera-Vique, M a Dolores Ruiz-López ⇑ , Manuel Olalla, Reyes Artacho, Rafael Giménez, Verónica Quintana, Triana Bergillos Dpto. de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Granada, Campus de Cartuja, C.P. 18012 Granada, Spain article info Article history: Received 21 December 2010 Received in revised form 23 March 2011 Accepted 19 May 2011 Available online 25 May 2011 Keywords: Selenium Zinc Magnesium Calcium Goat and cow fermented dairy products Chemical composition Probiotic starter culture abstract We determined Se, Zn, Mg and Ca levels in 42 samples of goat and cow fermented milks which are widely consumed in Spain were determined. Atomic absorption spectrometry (hydride generation for Se and flame atomisation for remaining elements) was used as an analytical technique. Reliability of the proce- dure was checked. Only Mg levels in goat fermented milks were significantly higher to those found in cow fermented milks (p< 0.022). Important similarities in concentrations and behaviours for Mg and Ca have been observed. Mg contents were significantly correlated with Zn (r = 0.590; p< 0.001) and Ca (r = 0.344; p< 0.028) concentrations, Zn, Mg and Ca levels with protein content (r = 0.554, r = 0.479, r = 0.388, respectively), Mg levels with fats (r = 0.403; p= 0.011) and Se levels with carbohydrates (r = À0.379; p= 0.031). Mineral and macronutrient levels in yogurts with traditional probiotic starter cultures were not significantly different to those found in fermented milks with additional probiotic microorganisms (p> 0.05). It was concluded that goat fermented milks are a better source for Mg than cow samples. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction In recent decades, an increasingly important role in the human diet has been attached to goat milk, since it possesses unique prop- erties which distinguishes it from cow milk and makes it a valuable alternative. The fat globules of goat milk are smaller than those of cow milk and probably this is one of the reasons for the easy diges- tion of goat milk. There are also differences in the fatty acid profile between the two kinds of milk. Goat milk presents a higher per- centage of short and medium-chain fatty acids than cow milk. For this reason, goat milk is used for treatment of malabsorption syndromes, intestinal disorders, coronary diseases, premature in- fant nutrition, cystic fibrosis, and other pathologies (Kondyli, Kats- iari, & Voutsinas, 2007; Park, Juárez, Ramos, & Haenlein, 2007). In addition, total conjugated linoleic acid (CLA) mean content seems to decrease in the following order: ewe > cow > goat milk fat (Park et al., 2007). CLA has been related to anticarcinogenic and antiath- erogenic properties and other human beneficial effects (Haro, Arta- cho, & Cabrera-Vique, 2006). Micelle structures in goat milk differ in average diameter, hydration, and mineralisation. Proportions of j-casein and espe- cially b-casein are higher in goat than in cow milk, and the a s1 -casein in goat milk contributes to a softer curd than does than in cow milk. This is probably another reason for the better diges- tion of goat milk compared to cow milk (Kondyli et al., 2007). In addition, the better tolerance of goat milk by infants and children suffering from hypersensitivity to cow milk (direct or indirect milk allergy) could be attributed to the differences in proteins between the two kinds of milk (Kondyli et al., 2007; Olalla et al., 2009; Park et al., 2007). Non-protein nitrogen content of goat milk is higher than in cow milk (Olalla et al., 2009; Park et al., 2007); this nitro- gen fraction is nutritionally important for humans due to its ele- vated level present in human milk where it can constitute up to a 25% of total nitrogen (Olalla et al., 2009). Taurine in goat milk de- rived from sulphur-containing amino acids has important meta- bolic functions. Lactose content of goat milk is about 0.2–0.5% less than that of cow milk (Park et al., 2007). Mineral and vitamin contents of goat milk are mostly higher than in cow milk (Cash- man, 2003; Nestares et al., 2008). On the other hand, goat milk dif- fers from cow milk in having better digestibility, alkalinity, buffering capacity and certain therapeutic values in medicine and human nutrition (Kruger et al., 2008; Park et al., 2007). Dairy goat farming is a vital part of the national economy in many countries, especially in the Mediterranean and Middle East region and is particularly well organised in France, Italy, Spain, and Greece (Park et al., 2007). However, large-scale industrialisa- tion of the dairy products from goat milk is limited. For example, goat milk in Spain is mainly used for cheese making and recently there is increasing consumption of fluid milk and several 0308-8146/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodchem.2011.05.090 ⇑ Corresponding author. Tel.: +34 958243869; fax: +34 958249577. E-mail address: mdruiz@ugr.es (M.D. Ruiz-López). Food Chemistry 129 (2011) 1126–1131 Contents lists available at ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem