Properties of extruded snacks supplemented with amaranth grain grits

Abstract

Extruded amaranth grain products have specific aroma and can be used as snack food, supplement in breakfast cereals, or as raw material for further processing. Extruded products of corn-amaranth grits blends, containing 20% or 50% amaranth grain grits, were produced by extrusion-cooking using a laboratory Brabender single screw extruder 20 DN. Extrudates with various texture were obtained. During extrusion process starch granules are partially degraded, hence rheological properties were examined. All samples exhibited thixotropic flow behavior. Those samples in which part of the corn grits was replaced with amaranth one had lower viscosity and exhibited lower level of structuration during storage

Development of an Expanded Snack of Rice Starch Enriched with Amaranth by Extrusion Process

“…The hardness values of the amaranth formulations were higher than those reported by Dokić et al [50] in corn snacks (18.4–19.2 N); these differences are mainly due to the moisture content in the feed that was lower (16%), and higher temperature (160 °C) in the extrusion die. However, the trend turned out to be similar to that observed in the present investigation; the increase in amaranth content reduced the force required to break the extrudate.…”

“…The micrographs exhibit the lubricating effect exerted by the oil content in this pseudocereal, limiting the complete gelatinization of the starch and the development of larger pores. Dokić et al [50] in their research on an extruded corn snack supplemented with amaranth obtained a similar behavior. A 50% increase in amaranth content reduced the size of the air cells when compared to their corn control (100%).…”

Utilization of Amaranthus spp. grains in food

“…During extrusion, starch granules undergo partial gelatinization and affect the expansion index of the final product. The addition of 20 or 50% of amaranth grits to corn grits decreased the paste viscosity in comparison to pure corn grits and decreased the quality of an extruded product by increasing its density and hardness and lowering the expansion index (Dokić, Bodroža-Solarov, Hadnađev & Nikolić, 2009). In contrast, the study of Ramos Diaz et al (2013) showed that the highest expansion index was achieved in extrudates containing amaranth (20% amaranth 80% corn) whereas the lowest in pure corn extrudates.…”

Avaliação da qualidade tecnológica de snacks obtidos por extrusão de grão integral de amaranto ou de farinha de amaranto desengordurada e suas misturas com fubá de milho

“…Observou-se que quanto maior o teor de grãos de amaranto, menor o volume específico e maior a tensão de cisalhamento dos snacks extrudados (r = -1,00; p = 0,011). Esse efeito do amaranto integral também foi observado por Ilo et al (1999), ao extrusarem misturas de farinha de arroz com 20 a 60% de grão de amaranto, e por Dokić et al (2009), ao extrusarem misturas de fubá de milho com 20 e 50% de fubá de amaranto, e também por Ascheri et al (2005), ao extrusarem misturas de farinha de arroz com 13 a 47% de farinha de amaranto integral.…”

“…A utilização do amaranto para elaboração de produtos extrudados resultou em snacks e cereais matinais com melhor valor nutritivo do que os similares comerciais, como observado por Chavez-Jauregui et al (2000 e Coelho (2006). A farinha de amaranto desengordurada vem sendo utilizada para elaboração de extrudados expandidos diretos, mas poucos estudos têm explorado a extrusão do grão integral de amaranto (ILO et al, 1999), do fubá de amaranto (DOKIĆ et al, 2009) ou da farinha de amaranto integral (ASCHERI et al, 2005); tal fato se deve, provavelmente, ao alto conteúdo de lipídeos (8%) do grão de amaranto, que pode atuar como um lubrificante, reduzindo o atrito necessário durante o processo de cocção por extrusão (ILO et al, 1999). A extrusão direta poderia reduzir os custos de produção por meio da eliminação das etapas de moagem e de desengorduramento do grão de amaranto, além de atender a crescente demanda por produtos à base de grãos integrais.…”