Glabrous canaryseeds were recently approved for human consumption as a novel cereal grain in Canada and the United States. Previously, canaryseeds were exclusively used as birdseed due to the presence of carcinogenic silica fibers; therefore the nutritional value of the seeds has been seriously overlooked. Two cultivars of glabrous canaryseeds (yellow and brown) were created from the hairy varieties. They are high in protein compared to other cereal grains, and contain high amounts of tryptophan, an amino acid normally lacking in cereals, and are gluten-free. Bioactive peptides of canaryseeds produced by in vitro gastrointestinal digestion have shown antioxidant, antidiabetic, and antihypertensive activity. The seeds contain other constituents with health promoting effects, including unsaturated fatty acids, minerals, and phytochemicals. Anti-nutritional components in the seeds are comparable to other cereal grains. Because of their beneficial health effects, canaryseeds should be regarded as a healthy food and have immense potential as a functional food and ingredient. Further research is required to determine additional bioactive peptide activity and capacity, as well as differences between the yellow and brown cultivars.

The bioactive properties and health-promoting effects of two novel yellow (C09052, C05041) and two brown (Calvi, Bastia) hairless canary seed (Phalaris canariensis L.) cultivars were investigated in comparison to two common cereal grains (wheat and oat). The cereal flours were digested using the standardized INFOGEST in vitro human gastrointestinal digestion model. The three-kilo dalton molecular weight cutoff (3 kDa MWCO) permeate of the generated digestates was assessed in vitro for their antioxidant, chelating, antihypertensive and antidiabetic activities. The results showed no significant differences in studied bioactivities between yellow and brown canary seed cultivars, except for antioxidant activity by the DPPH and chelating Fe2+ assays, where brown cultivars had higher activities. Canary seeds had superior or equivalent antioxidant activity than those from oat and wheat. The anti-hypertensive activity (Angiotensin-converting enzyme (ACE) inhibition) in yellow canary seed cultivars was significantly higher than that of oat and wheat, particularly for C09052 and Calvi varieties. Peptides exhibiting the highest antihypertensive activity from the permeate of the C09052 canary seed variety were further fractionated and identified by mass spectrometry. Forty-six peptides were identified belonging to 18 proteins from the Pooideae subfamily. Fourteen of the parent proteins were homologous to barley proteins. Peptides were analyzed in silico to determine potential bioactivity based on their amino acid composition. All 46 peptides had potential anti-hypertensive and anti-diabetic activities and 20 had potential antioxidant activity, thereby validating the in vitro assay data. Canary seed peptides also exhibited potential antiamnestic, antithrombotic, immunostimulating, opioid and neuro-activity, demonstrating important potential for health promoting effects, particularly against cardiovascular disease.

Hairless canary seed (Phalaris canariensis L.) is a novel true cereal that is now approved for human consumption in Canada and the United States. This true cereal grain has higher protein content (22%) than oat (13%) and wheat (16%) and represents a valuable source of plant proteins. Assessment of canary seed protein quality is therefore essential to evaluate its digestibility and ability to provide sufficient amounts of essential amino acids for human requirements. In this study, the protein nutritional quality of four hairless canary seed varieties (two brown and two yellow) were evaluated in comparison to oat and wheat. The assessment of anti-nutrients contents (phytate, trypsin inhibitor activity, and polyphenols) showed that brown canary seed varieties had the highest content in phytate and oat the highest in polyphenols. Trypsin inhibitor level was comparable among studied cereals, but slightly higher in the brown canary seed Calvi variety. In regard to protein quality, canary seed had a well-balanced amino acid profile and was particularly high in tryptophan, an essential amino acid normally lacking in cereals. The in vitro protein digestibility of canary seeds as determined by both the pH-drop and INFOGEST (international network of excellence on the fate of food in the gastrointestinal tract) protocols appears slightly lower than wheat and higher than oat. The yellow canary seed varieties showed better overall digestibility than the brown ones. For all studied cereal flours, the limiting amino acid was lysine. The calculated in vitro PDCAAS (protein digestibility corrected amino acid score) and DIAAS (digestible indispensable amino acid score) were higher for the yellow C05041 cultivar than the brown Bastia, similar to those of wheat, but lower than those of oat proteins. This study demonstrates the feasibility and utility of in vitro human digestion models for the assessment of protein quality for comparison purpose.