PRETREATMENT OF DATE SYRUP TO INCREASE CITRIC-ACID PRODUCTION

Pretreatment of date syrup with sulfuric acid, tricalcium phosphate, t ricalcium phosphate with hydrochloric acid, potassium ferrocyanide, an d EDTA to increase the production of citric acid was investigated. Amo ng the above techniques used for the removal of heavy metals, 2% trica lcium phosphate treatment gave better results regarding citric acid co ncentration (55 +/- 1.5 g l(-1)), citric acid yield (50 +/- 1.5%), and sugar utilization (73.3 +/- 1%). The optimum pH for citric acid produ ction was 6.5. The addition of 4% (v/v) methanol in the date syrup sol ution treated with 2% tricalcium phosphate increased the concentration of citric acid from 55 to 90 g l(-1). (C) 1997 Elsevier Science Inc.