Protein Quality of Amaranth Grain
J. P. Senft’s 1980 report assessed grain amaranth as a dietary protein source, comparing its essential-amino-acid pattern and protein quality with those of other grains. The historical comparison identified leucine as the principal limiting amino acid and reported a relative protein score of 67 for amaranth. The findings provide an early assessment of the nutritional potential of amaranth grain protein.
What the study did and found
J. P. Senft’s 1980 report examined the protein quality of grain amaranth and its potential value as a dietary protein source. It focused on the balance of essential amino acids and compared amaranth with conventional grains.
In the historical comparison, grain amaranth was reported at approximately 15% protein with a relative protein score of 67. The comparison placed it above corn, wheat, barley and oats, but below buckwheat and soybeans. These values reflect the protein-quality framework used in the report rather than modern clinical measurements.
Leucine was identified as the first limiting amino acid for amaranth, unlike several common cereals for which lysine was limiting. Other amino acids discussed as relatively low included threonine, isoleucine and valine. The findings supported interest in amaranth as a complement to cereal-based diets, not a claim that its protein was nutritionally complete.
Why it is cited
Senft’s publication is an early contribution to the renewed scientific evaluation of grain amaranth as a food crop. It emphasized that the amount of protein alone does not determine nutritional quality; essential-amino-acid balance is also important.
The comparative protein score and identification of leucine as the first limiting amino acid helped distinguish amaranth from cereals whose protein was chiefly limited by lysine. These comparisons informed later research on complementary plant-protein sources.
Its scope was the historical comparison of grain-amaranth protein quality and essential-amino-acid limitations. Subsequent research broadened the evidence by examining processing effects, cultivar variation and biological measures of protein quality.
The original report evaluated grain-amaranth protein quality using the comparative assessment methods available in 1980. Its findings provide historical evidence of differences in essential-amino-acid balance among grains but do not establish modern measures of protein digestibility or utilization. Later experiments involving different amaranth varieties, processing methods and animal models should be considered separately from Senft’s original findings. |
The topic today
Later investigations expanded the evidence on grain amaranth by studying different species and cultivars, amino-acid composition, digestibility and food processing. Such findings provide context but are not results of Senft’s 1980 report.
The historical relative protein score of 67 is a comparison within the assessment method used at the time. It should not be treated as a percentage of protein absorbed or as a modern measure of protein utilization.
The report remains useful for understanding why amaranth attracted attention as a potential complementary plant-protein source. Current nutritional evaluations require additional evidence about digestibility, processing and dietary context.