Improving Carotenoid Extraction from Tomato Waste by Pulsed Electric Fields

Abstract

In this investigation, the influence of the application of pulsed electric fields (PEFs) of different intensities (3–7 kV/cm and 0–300 μs) on the carotenoid extraction from tomato peel and pulp in a mixture of hexane:acetone:ethanol was studied with the aim of increasing extraction yield or reducing the percentage of the less green solvents in the extraction medium. According to the cellular disintegration index, the optimum treatment time for the permeabilization of tomato peel and pulp at different electric field strengths was 90 μs. The PEF permeabilization of tomato pulp did not significantly increase the carotenoid extraction. However, a PEF treatment at 5 kV/cm improved the carotenoid extraction from tomato peel by 39% as compared with the control in a mixture of hexane:ethanol:acetone (50:25:25). Further increments of electric field from 5 to 7 kV/cm did not increase significantly the extraction of carotenoids. The presence of acetone in the solvent mixture did not positively affect the carotenoid extraction when the tomato peels were PEF-treated. Response surface methodology was used to determine the potential of PEF for reducing the percentage of hexane in a hexane:ethanol mixture. The application of a PEF treatment allowed reducing the hexane percentage from 45 to 30% without affecting the carotenoid extraction yield. The antioxidant capacity of the extracts obtained from tomato peel was correlated with the carotenoid concentration and it was not affected by the PEF treatment.

Enhancing the carotenoid content of tomato fruit with pulsed electric field treatments: Effects on respiratory activity and quality attributes

“…Additionally, the inverse correlation found between the firmness of tomato and both TCC (r = -0.60, p < 0.001) and LC (r = -0.63, p < 0.001) ( Supplementary table 1) suggests that those conditions leading to the highest carotenoid content were also those resulting into the highest firmness loss. This could in turn favour the extraction of carotenoids from the food matrix, as reported for other vegetable tissues after the application of PEF treatments (Luengo et al, 2014a;Zderic et al, 2013).…”

Pulsed Electric Fields for the Treatment of Olive Pastes in the Oil Extraction Process

“…Solid-liquid extraction is a process for recovering desired compounds under the influence of a concentration gradient and by using solvents. Luengo et al [11] investigated the influence of different PEF intensities (3-7 kV/cm and 0-300 ms) on carotenoid extraction from tomato peel and pulp. They found that PEF treatment at 5 kV/cm improved carotenoid extraction by 39% compared to control samples and reduced the solvents percentage from 30% to 45% without affecting the carotenoid extraction yield.…”

Comparison of lycopene changes between open‐field processing and fresh market tomatoes during ripening and post‐harvest storage by using a non‐destructive reflectance sensor

“…11,12 The content of lycopene also differs between the parts of the fruit in which it occurs: in the skin, it is about five times more than in the tomato pulp. [13][14][15] Therefore, it is important to specify the part of the fruit on which the lycopene content is analysed. Lycopene is synthesized in the temperature range of 15-22 ∘ C (some sources give 12-26 ∘ C).…”