Use of rose oil in probiotic fermented whey as a functional food.

Medicinal use of phytochemicals dates back to ancient times. Following that, in the 1980s those phytochemicals because of their chemical composition were used to produce new functional foods with added health benefits. Based on their positive effects, nowdays phytochemicals are integrated into the composition of various food products such as whey. This study aimed to develop a functional beverage using probiotics, inulin and rose oil (0.5%, 1% and 2%) and to reveal their effects on some quality properties of the product during 28 days of storage. Lactobacillus acidophilus simultaneously with Bifidobacterium animalis were inoculated into reconstituted whey and inulin was added to enhance their growth and survival in the gastrointestinal tract. Beverage containing 0.5% rose oil (group D) was the most preferred and at the 28th day of storage contained 8.70 log10 cfu/ml, which is essential for a product to have probiotic properties. Microbiological evaluations including rose oil sample showed the absence of coliform in all the samples, while total mesophilic aerobic, yeast and mould counts showed no significant differences related to rose oil during storage period. Groups C, D, E and F had low pH values while group E exhibited the highest acidity level with its highest value (1.6% LA) at the 21st day. For the most part of storage period, group C had the highest levels of total solids while groups D, E and F had higher amounts of protein. Through storage duration, in all groups (except group B) the levels of ash, total solids and protein decreased. © Association of Food Scientists & Technologists (India) 2020.