Effects of grain source and processing methods on the nutritional profile and digestibility of grain amaranth

[Display omitted] •Processing of amaranth grain impacts lipid and protein digestion.•Amaranth flours were digested to a greater extent than the puffed amaranth.•Differences in lipid digestion were recorded between the 14 seedlots.•Cell wall restricted nutrients digestion of amaranth grains.•The geographic origin of the amaranth grains did not affect their microstructure. Amaranth grain is reputed to have a high nutritional value, and as a plant, be tolerant to adverse weather conditions. This suggests that grain amaranth could be useful in tackling malnutrition and the growing burden of cardiometabolic diseases. However, there is insufficient knowledge at present about how the nutrient composition and digestibility of amaranth grain varies with growing environment, crop genotype, and post-harvest processing. We investigated the effect of the source and processing of amaranth grains on the digestibility of protein and lipid present in the grains. There was variation in the composition and digestibility of raw grains from different sources, indicating a role of genotype and/or growing environment which warrants further investigation. The greatest differences in digestibility were measured between the different processing techniques. This indicates that efforts to increase the cultivation and consumption of grain amaranth need to be supported by education about effective processing and preparation techniques.