Isoflavones supplementation of a probiotic soy product: effects on quality characteristics and isoflavones profile

The aim of the present study was to investigate the effect of isofl avones supplementation of a fermented soy product on its sensory acceptance, physicochemical properties and probiotic cell viable count. Additionally we also investigated the ability of the mixed starter cultures (Enterococcus faecium CRL 183 and Lactobacillus helveticus 416) to modify the isofl avones profi le of soy product during the fermentation process. Three products were analysed: soy product fermented with E. faecium CRL 183 and L. helveticus 416, isofl avonessupplemented soy product (fermented with E. faecium CRL 183 and L. helveticus 416; 50mg/100g, Isofl avin®, Galena, Brazil) and unfermented soy product. A panel of judges evaluated the acceptability of the samples on a nine point structured hedonic scale. The chemical composition namely fat, protein, ash and total carbohydrate contents, pH, enumeration of viable Lactobacillus spp. and Enterococcus spp. and quantifi cation of isofl avones using HPLC were investigated. All determinations were conducted after 7 days storage at 10°C. The sensorial acceptance was reduced in the isofl avones-supplemented soy product, but this effect was not signifi cant compared to the sample without isofl avones addition. Chemical composition did not differ (p