Qualidade de laranjas ‘Navelina’ e ‘Valencia late’ produzidas no modo de produção biológico, em comparação com a produção convencional

The organic citrus production can be effective in reducing the environmental impact of farming as well as fruit quality can be improved. In this study, the fruits of the cultivars 'Navelina' and 'Valencia late' under identical soil and climatic conditions, but with different production systems, were compared. Commercial fruits were sampled from orange orchards located in nearby properties, under organic and conventional production systems. The fruit quality was determined by physical and chemical analysis (fruit color and skin thickness, the total soluble solids and the total acidity of the juice) and by organoleptic assessment, performed with a minimum of 44 panelists for each pair of samples. This evaluation took into account the external characteristics of the fruit (appearance and color), the internal characteristics (pulp appearance, texture, consistency and smell) and gustatory characteristics (flavor, acidity and sweetness). The results demonstrated that organic fruits, despite having a thinner skin, had a lower quality, especially for cv. 'Navelina', as for the cv. 'Valencia late' organic oranges showed lower acidity and higher levels of color and maturity, than the conventional oranges. In most cases, the panel assigned identical or higher values to the conventional fruits. This suggests that, in order to produce high quality fruits, is not enough to respect the basic rules of organic production and is essential an accurate orchards management concerning irrigation, fertilization, weed control and control of pests and diseases.