Comparative evaluation of organic and conventional farming on chemical quality parameters and antioxidant activity in fruits

Abstract

The aim of this research was to determine some important quality parameters and the antioxidant activity of organic and conventional  oranges, limes and apples. Five samples of organic fruits with seal certification, organic fruits without seal certification and conventional fruits were acquired from supermarkets and farm in Rio de Janeiro, Brazil. Organic lime and orange showed higher mean values of acidity, being 4.5 and 34.8% higher, when compared to conventional fruit, respectively. There were no statistical differences (p>0.05) among organic lime and orange with seal certification, organic without seal certification and conventional fruits regarding the values of density and ascorbic acid. Total soluble solids of organic with seal certification and organic without seal certification in lime was 47.4 and 25.8% higher than conventional fruits. Few statistical differences were observed in acidity and total sugar for Sweet orange (Citrus sinensis L. Osbeck) and Lime (Citrus aurantifolia (Christm) Swingle). In relation to the apple samples, there is no significant difference between the physico-chemical analyzes of organic and conventional cultivars. Regarding antioxidant activity, an increase in the percentage of reduction of DPPH (1,1-diphenyl-2-picrylhydrazyl) radical was observed in organic with seal certification lime (18.4%) and orange (22.2%) in comparison to conventional fruit. In general, small differences were observed in chemical quality parameter contents of organically and conventionally grown fruits, however, organic fruits, sealed or not, showed higher antioxidant activity than conventional fruits, suggesting that modulation of these parameters due to alterations in the cultivation practice is unique to the specific species and cultivar of vegetables.

Keywords: Organic, orange, lime, apple, antioxidant activity, quality parameters

African Journal of Biotechniology, Vol 13(18), 1883-1890