Does Lactobacillus plantarum or ultrafiltration process improve Ca, Mg, Zn and P bioavailability from fermented goats’ milk? Triana Bergillos-Meca a,⇑ , Carmen Cabrera-Vique a , Reyes Artacho a , Miriam Moreno-Montoro a , Miguel Navarro-Alarcón a , Manuel Olalla a , Rafael Giménez a , Isabel Seiquer b , Maria Dolores Ruiz-López a a Departamento de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Granada, Campus de Cartuja, 18071 Granada, Spain b Departamento de Fisiología y Bioquímica de la Nutrición Animal, CSIC, Camino del Jueves, 10100 Granada, Spain article info Article history: Received 28 November 2014 Received in revised form 8 February 2015 Accepted 13 April 2015 Available online 21 April 2015 Keywords: Mineral bioavailability Simulated gastrointestinal digestion Caco-2 cells Fermented goats’ milk abstract Ca, Mg, Zn and P bioavailability from two experimental ultrafiltered fermented goats’ milks (one of them with the probiotic Lactobacillus plantarum and another one without it), and fermented goats’ milk sam- ples available in the market were evaluated. Solubility, dialysability and a model combining simulated gastrointestinal digestion and mineral retention, transport and uptake by Caco-2 cells were used to assess bioavailability. The highest Ca, Mg, Zn and P bioavailability values always corresponded to the fermented milk developed by our research group, which could be explained by the effect of milk ultrafiltration. The fermented milk with L. plantarum showed higher Ca retention than the ones without the microorganism, and major Ca uptake when compared to commercial products. This fact could be attributed to a positive effect exerted by the probiotic strain. Ó 2015 Elsevier Ltd. All rights reserved. 1. Introduction Goat milk it is easy to digest and tolerate and high in nutritional value (Bergillos-Meca et al., 2013a; Navarro-Alarcón et al., 2011). It provides oligosaccharides similar to human milk, more short- and medium-chain fatty acids, and high-quality, absorbable proteins, in comparison with cow’s milk (Hijano, 2010; Olalla et al., 2009). In addition, it affords larger amounts of some minerals, such as cal- cium (Ca), zinc (Zn) and magnesium (Mg), and highly available Ca and phosphorus (P), and favors iron (Fe) absorption and its deposition in target organs (López-Aliaga, Díaz, Nestares, Alférez, & Campos, 2009). Dairy-based functional foods account for nearly 43% of the mar- ket, which is almost entirely made up of fermented dairy products (Barbaros & Huseyin, 2010). The application of ultrafiltration to concentrate milk constituents could represent a great advance in the manufacture of cheese and dairy products, and it has been widely recognized in the last years, since it could provide far- reaching benefits to the organoleptic and nutritional properties (Gésan-Guiziou, 2013). Thus, it has been published that probiotic fermented milk prepared from goat milk concentrated by ultrafil- tration has better sensory properties and certain therapeutic values in human nutrition (Domagala, Wszolek, & Dudzinska, 2012; Martín-Diana, Janer, Peláez, & Requena, 2003). In this context, the putative probiotic strain Lactobacillus plan- tarum C4, isolated from a commercial kefir, is being tested. This strain could be of high significance for the dairy industry and for the healthcare, since it fulfills the in vitro criteria for the selection of potentially effective probiotic bacteria, has antimicrobial and immuno-modulating properties (Puertollano et al., 2008). Skimmed milk has previously been found to be an appropriate vehicle for the intragastric administration of lactobacilli to mice (Bujalance, Moreno, Jiménez-Valera, & Ruiz-Bravo, 2007). Therefore, this bacterium is being tested as a possible probiotic to be added in a functional fermented goat’s skimmed milk, as reported by Bergillos-Meca et al. (2013b) and Moreno-Montoro et al. (2013). Considering that the aforementioned food is a good source of minerals, it is of interest to determine not only the total element content of these products but also its bioavailability, which has gained increasing interest in the field of nutrition (Perales, Barberá, Lagarda, & Farré, 2007; Bergillos-Meca et al., 2013a). The ideal approach is to study bioavailability in humans, but human studies are time consuming, costly to perform and impractical for large-scale applications. As a previous step to in vivo techniques, in vitro methods are interesting, and generally consist of simulated gastrointestinal digestion, followed by determination of how much of the mineral is soluble or dialyses through a membrane of a http://dx.doi.org/10.1016/j.foodchem.2015.04.051 0308-8146/Ó 2015 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. Tel.: +34 639217021; fax: +34 958249577. E-mail address: trianab@ugr.es (T. Bergillos-Meca). Food Chemistry 187 (2015) 314–321 Contents lists available at ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem