Evaluation of the physical, chemical, technological, and sensorial properties of extrudates and cookies from composite sorghum and cowpea flours

• Ano de defesa: 2023
• Autor(a) principal: Mba, Joy Chinenye
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa; Ciência e Tecnologia de Alimentos
• Palavras-chave em Português: Allimento sem glútem; Taninos; Fenóis; Farinha como alimento; Ciência e Tecnologia de Alimentos
• Link de acesso: https://locus.ufv.br//handle/123456789/31521; https://doi.org/10.47328/ufvbbt.2023.307

In recent years, there has been a growing demand for gluten-free and functional products, driven by consumer preferences for healthier and more diverse food choices. Then, there is a need to explore new ingredients that can be used as alternatives to traditional gluten-containing grains like wheat. Sorghum and cowpea are two such ingredients that have great potentials. This work evaluated the physical, chemical, technological, and sensorial properties of extrudates and cookies from composite sorghum and cowpea flour. Extrudates and cookies were produced from composite flour of sorghum and cowpea, at ratios (sorghum: cowpea) of 70:30, 50:50 and 30:70. The control samples were 100% sorghum and cowpea extrudates and cookies. Raw flour, extrudates and cookies were characterized (dietary fiber, resistant starch, proteins, antioxidant capacity, pasting properties, etc). Results obtained for particle size distribution and bulk density indicated that the addition of cowpea flour decreased the particle sizes of flour but increased the bulk densities. Also, the addition of cowpea flour increased the expansion ratio of cookies, but did not affect the weight loss. Color parameters (L*, a*, b*, H, and C) for extrudates were increased with the addition of cowpea flour, but that of cookies were not affected. Furthermore, the proximate composition results obtained for flour, extrudates and cookies differed significantly (p<0.05). The protein, ash, and dietary fiber contents were observed to increase with an increase in the percentage substitution of cowpea flour. In addition, the values obtained for free phenolics ranged between 0.62-45.34 mg GAE/g, values for tannin ranged between 0.38-47.25 mg Catechin equiv./g, antioxidant capacity ranged from 7.40-211.20 Micromole TE/g sample and that of resistant starch ranged from 0.16-36.29 g/100g. Free phenolics, tannin, and antioxidant capacity decreased with increase in percentage addition of cowpea flour. The addition of cowpea flour increased the crispiness of extrudates, but was not observed to play a role in the hardness of cookies. On the other hand, pasting properties of flour, extrudates and cookies decreased with addition of cowpea flour. Finally, the sensory evaluation scores for extrudates and cookies indicated that the products had good acceptability, with all evaluated products having scores above the cutoff score of 5. In conclusion, gluten-free extrudates and cookies of good acceptability can be produced from sorghum flour with up to 50% substitution of cowpea flour. Keywords: Gluten-free cookie. Phenolics. Tannins. Antioxidant capacity. Resistant starch. Extrusion. Baking.