Pasting properties of raw and extruded cowpea cotyledons flours

Abstract There is little research on the viscosity profile analysis of cowpea cotyledon flour (CCF). Due to the new ways of using pulses grains in the diet, it is important to evaluate the viscoamylographic behavior of raw and processed CCF. The CCF was obtained from the cultivars BRS Guariba and BRS Novaera and evaluated in the Rapid Visco Analyzer (RVA). For raw CCF it was used the “Standard 1” program. The extruded CCF was obtained from the cultivar BRS Guariba, which was processed following a central rotational composite design, combining thermoplastic extrusion temperatures (124; 130; 145; 160; 166 °C) and conditioning moisture (16.2%; 17%; 19%; 21%, 21.8%). The obtained extrusions were ground (Ø > 0.5 mm) and evaluated in the RVA using the program “Extrusion 2”. The raw CCF from BRS Guariba presented higher protein, lipid and mineral content and lower carbohydrate content than BRS Novaera. The raw CCF from BRS Guariba showed lower values of pasting temperature (79.35 °C), viscosity breakdown (103.00 cP) and seatback (1447.33 cP) compared to raw CCF from BRS Novaera. The extrusion process drastically changed all viscosity parameters, increasing the initial viscosity value and decreasing the value of other parameters. The extruded CCF had different pasting properties. CCF extruded at 166 °C and 19% moisture resulted in flours with higher initial viscosity and lower retrogradation values, which can be used as a thickener in food products, in addition to increase nutritional value. Resumo Há poucas pesquisas sobre a análise do perfil de viscosidade de farinhas de cotilédone de feijão-caupi (FCFC). Devido às novas formas de utilização dos grãos de pulses na dieta, torna-se importante avaliar o comportamento viscoamilográfico de FCFC cruas e processadas. As FCFC foram obtidas das cultivares BRS Guariba e BRS Novaera e avaliadas no Rapid Visco Analyzer (RVA). Para a FCFC crua foi utilizado o programa “Standard 1”. As FCFC processadas foram obtidas da cultivar BRS Guariba, que foi extrusada seguindo um delineamento composto central rotacional, combinando temperaturas de extrusão termoplásticas (124; 130; 145; 160; 166 °C) e umidade de condicionamento (16,2%; 17%; 19%; 21%; 21,8%). Os extrusados obtidos foram moídos (Ø > 0,5 mm) e avaliados no RVA utilizando o programa “Extrusion 2”. A FCFC crua da BRS Guariba apresentou maior teor de proteínas, lipídios e minerais e menor teor de carboidratos que a BRS Novaera. A FCFC crua da BRS Guariba apresentou valores i