Optimization of Lycopene Extraction from Tomato Processing Waste Using an Eco-Friendly Ethyl Lactate-Ethyl Acetate Solvent: A Green Valorization Approach

摘要

Lycopene is a highly-prized antioxidant with associated health benefits and is abundant in natural sources. A green valorization approach was used to extract lycopene from tomato processing waste. Ultrasound-assisted extraction was applied to the tomato waste using an eco-friendly solvent mixture containing ethyl lactate and ethyl acetate for the extraction of lycopene. Extraction parameters were: X-1 = extraction temperature (degrees C), X-2 = proportion of ethyl acetate in solvent mixture (% v/v), X-3 = solvent:sample ratio (mL/g), and X-4 = extraction time (min). A Box-Behnken design was used to define experimental conditions, and response surface methodology was then conducted to determine the optimized conditions: X-1 = 63.4 degrees C, X-2 = 30% (v/v), X-3 = 100 mL/g, and X-4 = 20 min. The experimental optimized extraction yield of lycopene was 1334.8 mu g/g (d.w.), in agreement with the predicted yield. At the same conditions without ultrasound, a yield of 1209.5 mu g/g (d.w.) was obtained (9.4% lower). Ultrasound increases extraction yield, and tomato processing by-products are a viable alternative source of extractable lycopene. This represents a greener strategy for the extraction of lycopene in comparison to conventional methods using organic solvents, and shows a promising alternative use for a food processing waste.