Influence of milk ultrafiltration on Ca, Mg, Zn and P levels in fermented goats' milk

- Ca, Mg, Zn and P levels from different fermented goats' milks were evaluated.
- Ultrafiltered fermented milk presented higher Ca and Mg concentrations than raw milk.
- Ultrafiltered fermented milk showed higher mineral levels than commercial products.
- Ultrafiltration seems to increase Ca, Zn and P levels versus traditional methods.
- Ca, Mg, Zn and P levels showed similarities in their behaviours in these products.

The application of ultrafiltration process has been proposed and used as an alternative to the addition of powdered milk in the production of fermented goats' milk. However, data about the effects of this process on nutritional properties of the final products are scarce. We evaluated the influence of milk ultrafiltration on Ca, Mg, Zn and P levels in experimental fermented goats' milks, in comparison to the raw milk and commercial fermented goats' milks. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used as analytical technique for Ca, Mg and Zn, and UV/VIS spectrophotometry for P. Ca and Mg levels in our experimental fermented products were significantly higher than in raw milk. In addition, higher contents of Ca, Zn and P were observed in the experimental ultrafiltered fermented goats' milk, in comparison to the commercial ones. Significant linear correlations among Ca, Mg, Zn and P levels demonstrated the existence of important similarities in their behaviours in these products. It was concluded that ultrafiltration increases Ca, Zn and P concentrations and our products may constitute a better source of minerals compared to other products already on the market. Ultrafiltration could represent a great advance to concentrate milk for higher nutritional values fermented products manufacture.