Quantificação de compostos bioativos e capacidade antioxidante em cultivares de feijão-caupi.

Abstract

The beans is a legume that is widely consumed in the world, being it associated different nutritional properties. With the present study aimed to evaluate the influence of cooking on the chemical composition, bioactive compounds and antioxidant capacity of cowpea cultivars. Eight cultivars were analyzed: Costa de Vaca, Marataoã BRS, BRS Itaim, BR-17 Gurguéia, BRS Novaera, Paulistinha, Setentão and Patativa. The grain of each cultivar were submitted to two different procedures for carrying out the analyzes: raw (homogeneous powder) and cooked (maceration) under pressure. Was analyzed the chemical composition of samples that included the chemical composition, with determination of moisture, ash, lipids, proteins, carbohydrates and energy, the physical and chemical parameters such as pH, acidity and sugar, in addition to analyzes of bioactive compounds such as phenolic compounds, ascorbic acid, flavonoids, anthocyanins and antioxidant capacity. All analyzes were carried out in quadruplicate in raw varieties, cooked and cooking broth and the results expressed as mean ± standard deviation. We conducted the analysis of variance and the means were compared by Tukey test (p <0.05). With respect to chemical composition, moisture content was in the 7-11% range in the raw samples and increased the cooked (60-70%). The protein content significantly decreased (p <0.05) for all baked varieties, as well as ash, carbohydrates and energy value in the eight cultivars. For the content of total and reducing sugars, the raw samples showed levels of 11-13 mg / 100 g and 2-3 mg / 100 g respectively, after cooking, it was observed a reduction in these levels. For bioactive compounds, BRS Marataoã had the highest total phenolic content before cooking (112.15 mg / 100 g), after cooking there was a reduction of these compounds in all cultivars with levels of 12-15 mg / 100g, and the broth showed higher contents ranging from 11-52 mg / 100 g. small concentrations of anthocyanins were found in raw varieties, cooked in broth and cooking, especially BRS Novaera (1.24 mg / 100g-1) in its cooked form. For the antioxidant capacity, there were different behaviors for each cultivar in the assessed method. Before cooking, BRS Marataoã showed higher antioxidant capacity (57.69 g beans. DPPH-1g). After cooking, the cooking broth showed better results compared to baked beans for six of the eight cultivars, especially to cultivate Costa cow. strong correlation between antioxidant capacity and phenolic content, total flavonoids and ascorbic acid was found. It was concluded that after processing, cultivars maintained relevant nutritional and functional characteristics, it is recommended to cowpea consumption with broth cooking for retaining compounds with antioxidant properties.