Microbial Production of Citric Acid by Solid State Fermentation of Kiwifruit Peel

Abstract

ABSTRACT A solid‐state fermentation method was developed for the production of citric acid from kiwifruit peel by Aspergillus niger NRRL 567. This method produced about 100g citric acid per kg of kiwifruit peel fermented in the presence of 2% methanol at 30°C in 4 days. The yield was more than 60% based on the amount of fermentable sugar consumed.