Resumen El ajonjolí es usado principalmente para obtener aceite, generando una pasta de subproducto de ajonjolí rica en proteínas, fibra dietaria y fitoquímicos. La extrusión es una tecnología eficiente para obtener alimentos funcionales. El objetivo de este trabajo fue optimizar el proceso de extrusión para encontrar la mejor combinación de temperatura de extrusión (TE)/velocidad de tornillo (VT) y así producir harina de subproducto de ajonjolí extrudido optimizada (HSAEO), con altos valores de índice de absorción de agua (IAA), índice de solubilidad en agua (ISA), digestibilidad proteínica in vitro (DPIV), compuestos fenólicos totales (CFT) y actividad antioxidante (AAox). Se aplicó un diseño experimental central compuesto rotable con dos factores y cinco niveles. La función de deseabilidad fue empleada para optimizar las variables del proceso de extrusión. La mejor combinación de las variables del proceso de extrusión fue TE = 139 °C/VT = 80 rpm. La HSAEO presentó mayores valores de las respuestas evaluadas que la harina de subproducto de ajonjolí sin procesar, sugiriendo que podría ser usada en bebidas, papillas y postres.

Abstract Sesame is used mainly to obtain oil, generating a sesame by-product cake that is rich in protein, dietary fiber, and phytochemicals. Extrusion is an efficient technology to obtain functional foods. The aim of this work was to optimize the extrusion process to find the best combination of extrusion temperature (ET)/screw speed (SS) in order to produce optimized extruded sesame by-product flour (OESBF), with high values of water absorption index (WAI), water solubility index (WSI), in vitro protein digestibility (IVPD), total phenolic compounds (TPC), and antioxidant activity (AoxA). A rotatable composite central experimental design with two factors and five levels was applied. Desirability function was used to optimize the extrusion process variables. The best combination of extrusion process variables was ET = 139 °C/80 rpm. The OESBF showed higher values of evaluated responses than unprocessed sesame by-product flour, suggesting that OESBF could be used in beverages, porridges, and deserts.

Neste trabalho foram elaborados pellets expandidos a partir da mistura de 50% de Amido de Batata (AB), 35% de Milho de Qualidade Protéica (MQP) e 15% de Farelo de Soja (FS), utilizando extrusor de laboratório com matriz de 1,5 × 20,0 × 100,0 mm. As variáveis independentes analisadas foram: Temperatura de Extrusão (TE) (75-140 °C) e Umidade da Mistura (UM) (16-30%). O efeito das variáveis de extrusão foram estudadas quanto ao Índice de Expansão (IE), a densidade aparente (DA), força de penetração (FP), Energia Mecânica Específica (EME), perfil de viscosidade, DSC, cristalinidade através de difração de raio X e Microscopia Eletrônica de Varredura (MEV). A PF diminuiu de 30 para 4 kgf com o aumento de ambas as variáveis independentes (TE e UM). EME foi afetada somente pela UM, diminuindo com o aumento desta variável. A região otimizada mostrou que os melhores resultados foram obtidos utilizando TE na faixa de 123-140 °C e 27-31% UM, respectivamente. Pellets expandidos com características aceitáveis foram obtidos usando a mistura de amido de batata, milho de qualidade protéica e farelo de soja através de extrusão termoplástica.

A blend of 50% Potato Starch (PS), 35% Quality Protein Maize (QPM), and 15% Soybean Meal (SM) were used in the preparation of expanded pellets utilizing a laboratory extruder with a 1.5 × 20.0 × 100.0 mm die-nozzle. The independent variables analyzed were Barrel Temperature (BT) (75-140 °C) and Feed Moisture (FM) (16-30%). The effect of extrusion variables was investigated in terms of Expansion Index (EI), apparent density (ApD), Penetration Force (PF) and Specific Mechanical Energy (SME), viscosity profiles, DSC, crystallinity by X-ray diffraction, and Scanning Electronic Microscopy (SEM). The PF decreased from 30 to 4 kgf with the increase of both independent variables (BT and FM). SME was affected only by FM, and decreased with the increase in this variable. The optimal region showed that the maximum EI was found for BT in the range of 123-140 °C and 27-31% for FM, respectively. The extruded pellets obtained from the optimal processing region were probably not completely degraded, as shown in the structural characterization. Acceptable expanded pellets could be produced using a blend of PS, QPM, and SM by extrusion cooking.