Improving Fruity Aroma Production by Fungi in SSF using Citric Pulp

Abstract

Aromas produced by microorganisms can be recognized as natural and therefore have great economic potential. Ceratocystisfimbriata has the potential to produce a variety of aromas. The aim of the present work is to increase the fruity aroma production in citric pulp (CP), a waste from the citric juice production industry, using C. fimbriata in solid-state fermentation (SSF), testing other residues as carbon (sugarcane molasses, soya molasses) and nitrogen (soya bran or urea) sources. The studies were carried out in 250 mL Erlenmeyer flasks, pH 6.0, 75% initial moisture, 30 °C, inoculum rate 1 × 107 spores/g of CP, during 120 h. Total volatile compounds were quantified by headspace analysis in a gas chromatograph. The best production of volatile compounds was detected when the citric pulp was supplemented with 50% of soya bran, 25% of sugarcane molasses, and mineral saline solution. The production of total volatile reached 99.60 μmol/L g.