Solid-state fermentation for recovery of carotenoids from tomato waste

Tomato waste is an excellent source of nutrients, micronutrients, and bioactive compounds. Some extraction technologies have been used to recover these pigments for their proven biological activities. In this study, solid-state fermentation with Aspergillus niger GH1 was used as a bioprocess for carotenoid extraction and recovery in tomato waste. The chemical composition was evaluated, in addition to the viability of the tomato waste as a solid-fermentation substrate. The results showed that at 70% humidity, pH 4.0, 30 °C, 1 × 106 spores/g of inoculum concentration, and 36 h of fermentation gave the optimal yield. A biomass/carotenoids ratio of 0.164 mg/L of total carotenoids was realized. The number of carotenoids extracted from tomato waste was improved from 0.062 mg/L from zero hours of fermentation to 0.164 mg/L of total carotenoids after 36 h of fermentation. Solid-state fermentation with Aspergillus niger GH1 was a viable approach to enhance the extraction and recovery of carotenoids.