Optimisation of the recovery of carotenoids from tomato processing wastes: application on textile dyeing and assessment of its antioxidant activity

The present study has been focused on the extraction of natural pigments from tomato industry waste. At first, different solvents and solvents mixture were compared to determine which one is the best for extracting carotenoids compounds from tomato by-products. A mixture of hexane and acetone gave the highest carotenoids extraction yield among the others examined. The extraction conditions were optimised using a five-level-five-factor central composite design. Under optimal conditions, solvent solid ratio 90, hexane percentage in the solvent mixture 60, extraction duration 50, number of extractions 4 and extraction temperature 35 degrees C, the yield of carotenoids was 80.7 mu g/g. The coloured extract of tomato by-products was applied on textile fabrics to investigate the dyeing characteristics and antioxidant activities. The results indicate that extract can be applied on textile fabrics (wool, silk and polyamide) to produce coloured clothing with acceptable antioxidant properties. [GRAPHICS] .