Fed-Batch Production of a Fermented Beverage Containing Vitamin B۱۲

Production of fermented functional foods containing micronutrients is required for their health beneficial properties. The impact of ۱۱ process variables on vitamin B۱۲ production in a dairy beverage containing propionic acid was investigated. Propionibacterium freudenreichii ssp. shermanii was applied in a ۳-l fermentor in the fed-batch fermentation system. The most suitable conditions for vitamin B۱۲ production were achieved by ۵% v/v inoculum size containing Propionibacterium freudenreichii (without Lactobacillus acidophilus) and continuous feeding of lactose with the rate of ۰.۰۴ l/h at ۳۶°C in a medium containing ۲۵ g/L molasses, ۱۰ g/L corn steep liquor, at pH=۶.۵, after ۹۶ h fermentation. Maximum vitamin concentration (۳۰ mg/L) and productivity (۷.۵ mg/L.day) were obtained in trial ۹. Organoleptic properties of the fermented beverage were also acceptable for panelists and no significant difference was observed between samples and control during ۶ days refrigerated storage.

کلیدواژه ها:

Co-culture ، Fed-batch fermentation ، Plackett-Burman ، Process variables ، Propionibacterium freudenreichii ، Propionic acid ، Vitamin B۱۲