Effect of peel and seed removal on the nutritional value and antioxidant activity of tomato (Lycopersicon esculentum L.) fruits

- The effect of peel and seeds removal on 4 Portuguese tomato cultivars was studied.
- Peeling caused a higher decrease in lycopene, ascorbic acid, and phenolic contents.
- Seeds removal increased both color and sweetness of the fruits.
- Both procedures decreased the antioxidant activity of fruits from all cultivars.
- Rama fruits were the less affected by trimming procedures.

The effect of peel and seed removal, two commonly practiced procedures either at home or by the processing industry, on the physicochemical properties, bioactive compounds contents and antioxidant capacity of tomato fruits of four typical Portuguese cultivars (cereja, chucha, rama and redondo) were appraised. Both procedures caused significant nutritional and antioxidant activity losses in fruits of every cultivar. In general, peeling was more detrimental, since it caused a higher decrease in lycopene, β-carotene, ascorbic acid and phenolics contents (averages of 71%, 50%, 14%, and 32%, respectively) and significantly lowered the antioxidant capacity of the fruits (8% and 10%, using DPPH and β-carotene linoleate model assays, correspondingly). Although seeds removal favored the increase of both color and sweetness, some bioactive compounds (11% of carotenoids and 24% of phenolics) as well as antioxidant capacity (5%) were loss. The studied cultivars were differently influenced by these procedures. The fruits most affected by peeling were those from redondo cultivar (−66% lycopene, −44% β-carotene, −26% ascorbic acid and −38% phenolics). Seeds removal, in turn, was more injurious for cereja tomatoes (−10% lycopene, −38% β-carotene, −25% ascorbic acid and −63% phenolics). Comparatively with the remaining ones, the rama fruits were less affected by the trimming procedures.