Antioxidants of Amaranth, Quinoa and Buckwheat Wholemeals and Heat-Damage Development in Pseudocereal-Enriched Einkorn Water Biscuits

A viable approach to improve the nutritional quality of cereal-based foods is their enrichment with pseudocereals. The aim of this research was to evaluate the antioxidant properties of amaranth, quinoa and buckwheat, and the heat damage of water biscuits (WB) produced from either wholemeal or refined flour of einkorn and enriched with 50% buckwheat, amaranth or quinoa wholemeal. Buckwheat had the highest tocols content (86.2 mg/kg), and einkorn the most carotenoids (5.6 mg/kg). Conjugated phenolics concentration was highest in buckwheat (230.2 mg/kg) and quinoa (218.6 mg/kg), while bound phenolics content was greatest in einkorn (712.5 mg/kg) and bread wheat (675.7 mg/kg). The all-wholemeal WB had greater heat damage than those containing refined flour (furosine: 251.5 vs. 235.8 mg/100 g protein; glucosylisomaltol: 1.0 vs. 0.6 mg/kg DM; hydroxymethylfurfural: 4.3 vs. 2.8 mg/kg DM; furfural: 8.6 vs. 4.8 mg/kg DM). The 100% bread wheat and einkorn wholemeal WB showed greater heat damage than the WB with pseudocereals (furfural, 9.2 vs. 5.1 mg/kg; glucosylisomaltol 1.1 vs. 0.7 mg/kg). Despite a superior lysine loss, the amino-acid profile of the pseudocereals-enriched WB remained more balanced compared to that of the wheats WB.

Automated summary

Enriching cereal-based foods with pseudocereals is a viable way to improve their nutritional quality. This research evaluated the antioxidant properties of amaranth, quinoa, and buckwheat, as well as the heat damage of water biscuits made from einkorn flour and enriched with 50% buckwheat, amaranth, or quinoa. Buckwheat had the highest tocols content, while einkorn had the most carotenoids. Buckwheat and quinoa had the highest concentration of conjugated phenolics, while einkorn and bread wheat had the highest content of bound phenolics. The all-wholemeal water biscuits had greater heat damage compared to those with refined flour. Water biscuits made with 100% bread wheat and einkorn flour showed more heat damage than those with pseudocereals. Despite lysine loss, the amino acid profile of the pseudocereal-enriched water biscuits remained more balanced.