Biotechnol Appl Biochem 2019 Apr 17. Epub 2019 Apr 17.
Laboratory Reactions and Process Engineering (LRPE), UMR CNRS 7224, University of Lorraine, ENSAIA, Vandoeuvre Cedex, 54505, France.
The feasibility of baker's yeast production using fruits and peels of Opuntia ficus indica (OFI) as carbohydrate feedstock was investigated. Two response surface methodologies involving central composite face centered design (CCFD) were successfully applied. The effects of four independent variables on baker's yeast production from OFI fruit juice was evaluated using the first CCFD. The best results were obtained with 24 h of inoculum age, 30°C temperature, 200 rpm of agitation and 10% inoculum size. At the maximum point, the biomass concentration reached 9.29 g/L. A second CCFD was performed to optimize the sugar extraction from OFI fruit peels. The potential of these latter as a fermentation substrate was determined. From the experimental results, the OFI fruit peel is an appropriate carbon source for the production of baker's yeast. The maximum biomass concentration was 12.51g/L. Different nitrogen supplements were added to promote the yields of baker's yeast. Corn steep liquor was found to be the best alternative nutrient source of casein hydrolysate and yeast extract for baker's yeast production. This article is protected by copyright. All rights reserved.