Analysis of antioxidant compounds and hydroxymethylfurfural in processing tomato cultivars

Tomato (Lycopersicon esculentum) fruit is an important source of antioxidants, which are important in the prevention of many cancer types and cardiovascular diseases. In ripe tomato fruit, one of the most significant antioxidant compounds is lycopene. In this study, effects of the cultivars and the environmental conditions on the lycopene content were investigated. Temperature effect was characterized by calculating growing degree-day (GDD). Relationships among lycopene, total polyphenols, organic acid, and total antioxidant status (TAS) were analyzed. A variation of more than 30% was found among the lycopene levels of five processing tomato cultivars. Lycopene content ranged from 79.7 to 155.0 mg center dot kg(-1) fresh weight. There was a significant difference between the lycopene concentrations of fruit harvested at two different dates. The values were higher at the second harvest, probably due to the cooler weather conditions preceding that harvest. Total polyphenols correlated strongly with TAS but the other antioxidants did not have any relationship to TAS. GDD were strongly and positively correlated with hydroxymethylfurfural content in fresh tomatoes.