Process Biochemistry, Vol.37, No.7, 707-717, 2002
Low temperature and ambient temperature wine making using freeze dried immobilized cells on gluten pellets
Low temperature wine making using freeze-dried gluten supported biocatalyst (FGB) is reported to be feasible. The biocatalyst was prepared by cell immobilization of the strain AXAZ-1 on gluten pellets followed by freeze drying. Batch fermentations were performed and the effects of initial Be density, temperature and total acidity of must on kinetic parameters were examined. Improved results were shown by freeze-dried immobilized cells on gluten as compared with free freeze-dried cells (ffdc). Fermentation times obtained at low temperatures (5-15 degreesC) could be accepted in industry. The total acidity of grape must does not affect the fermentation time while freeze-dried immobilized cells seem to have an operational stability from batch to batch. Amyl alcohols, the main volatile, are reduced by the decrease of the temperature below 20 degreesC. The percentages of amyl alcohols as a function of total volatiles were reduced and those of ethyl acetate were increased by the decrease of temperature, indicating improvements in quality and nutritional value. (C) 2002 Elsevier Science Ltd. All rights reserved.