Yellow-coated quinoa (Chenopodium quinoa Willd) - physicochemical, nutritional, and antioxidant properties.

Quinoa seeds are an excellent source of nutrients and phytochemical compounds with well-documented activities; however, different cultivars are usually characterized by different physical properties and chemical composition. This study presented the physical properties, nutrient content, and antioxidant capacities of 25 cultivars of yellow-coated quinoa.

The results demonstrated that quinoa seeds may be an excellent source of dietary fibre (up to 198 g kg^-1 d.m. - Baer cultivar), with the 1:2 ratio of the soluble to insoluble fraction. Digestible carbohydrates were present at the highest level in the Puno cultivar (640 g kg^-1 ). The highest content of proteins was determined in the Colorado 407D and Faro cultivars (c.a. 16%). The average contents of albumin and globulins in the seeds were 29.2 and 65.6 g kg^-1 , respectively. The quinoa seeds were characterized by low activity of protease inhibitors. The lowest inhibition of trypsin was determined for the UDEC-3, Faro Orange, and Titicaca cultivars, while the highest value was exhibited by the Titicaca White and UDEC-5 cultivars. Phenolics in the tested cultivars ranged from 7.1 g kg^-1 (UDEC-3) to 10.6 g kg^-1 (Temuko). The best antiradical properties were determined for Temuco and Rainbow (2.05 g TE kg^-1 and 1.85 g TE kg^-1 , respectively), while the Baer and Temuco cultivars were characterized by the highest reducing power (2.28 g TE kg^-1 and 2.17 g TE kg^-1 , respectively).

This study has shown that quinoa cultivated in European countries are a good source of nutrients, dietary fibre, and antioxidants; however, their composition varies significantly. This article is protected by copyright. All rights reserved.