Abstract
PurposeThe purpose of this study was to evaluate the effects of the addition of flaxseed and amaranth at different proportions on the hydration kinetics, colour and sensory qualities of instant-extruded cereals, important aspects related to the functionality and acceptability of food products.Design/methodology/approachInstant-extruded cereals were made with different proportions of flaxseed (6.6–9.3%), amaranth (18.7–33.1%), and maize grits (63.8–67.3%); and characteristics such as hydration kinetics, colour parameters and sensory properties were evaluated.FindingsThe kinetics of milk absorption showed that the extruded cereals maintained their texture and crispness for a sufficiently long time (≤20 min). The L*, a* and chroma* values of the extruded cereals were significantly affected (p < 0.05) by the flaxseed content. Sensory evaluation showed that all the extrudates had good acceptance in terms of flavour, texture, and colour attributes in relation to high-fibre commercial cereals; according to the preference test, they were as acceptable as commercial extruded cereals when consumed with milk. The addition of high-fibre and protein-containing grains such as flaxseed (8.6–9.3%) and amaranth (18.7–22.9%) in instant-extruded cereals allowed the production of products with acceptable physical and sensory characteristics.Originality/valueIn this study a novel instant-extruded cereal with flaxseed and amaranth was developed. The evaluation of the physical and sensory characteristics of instant-extruded cereals is essential to guarantee consumer acceptability, especially if functional ingredients with a high content of dietary fibre and protein are added.