Production of Functional Fermented Milk Beverages Supplemented with Pomegranate Peel Extract and Probiotic Lactic Acid Bacteria

Fermented milk beverages supplemented with pomegranate peel extract and inoculated with Lactobacillus plantarum and Bifidobacterium longum subsp longum were produced. The antioxidant activity of fermented milk beverages supplemented with pomegranate peel 150 mg/L (FMPO 150) and 300 mg/L (FMPO 300) was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). In addition, the polyphenolic profile and sugars content were determined by HPLC analysis, and the volatile compounds were identified using GC-MS analysis. The effects of FMPO 150 and FMPO 300 (10 g/day) on the lipid profile and antioxidant/biochemical status of rats were also evaluated after 4 weeks of oral intake. Antioxidant activity of the fermented milk beverage FMPO 300 was higher than that of FMPO 150. GC-MS analysis of the volatile compounds revealed that diacetyl, acetoin, and acetaldehyde were the major constituents. FMPO 150 and FMPO 300 were efficient in reducing the LDL cholesterol and triacylglycerol and increased the HDL cholesterol in serum. Liver function biomarkers were not affected by the end of treatment (p<0.05). Also, the thiobarbituric acid-reactive substances (TBARS) were decreased, while the activity of antioxidant enzymes in the liver (GSH, CAT, SOD, and GPx) were increased. Hence, the combination of pomegranate peel extract and probiotic lactic acid bacteria in a fermented milk beverage provides not only probiotic benefits but also bioactive phenolic compounds that could be functional and possess therapeutic effects.