Exploring quinoa germination

Quinoa (Chenopodium quinoa Willd.), a pseudocereal belonging to the Chenopodiaceae family, is one of the best sources of protein in the vegetal kingdom. Indeed, 40 g of quinoa covers an important part of daily requirements of essential amino acids. Moreover, quinoa is a gluten-free grain and an important source of minerals, fiber and phenolic compounds. On the other hand, acceptability of quinoa is low due to the presence of saponins in its external layers. Besides being antinutritional compounds, saponins are well known for giving bitterness. In order to remove saponins, washing and/or pearling are carried out before quinoa consumption. However, washing contaminates water whilst pearling lowers its nutritional properties. Germination improves the technological, nutritional and sensory characteristics of both cereals and pseudocereals when process conditions are properly controlled. In this study, controlled germination has been explored as an alternative treatment to decrease quinoa bitterness, avoiding polluting processes and nutrient losses. Seeds were germinated at 22 ºC up to 72 hours and then gently dried. Germination decreased total starch content from 61.3 to 52.3 % db. It increased the protein amount from 14.6 to 16.4 % db after 48 h. Currently, changes in protein hydrophobicity is under evaluation. The content of bitter compounds such as saponins, phenols and flavonoids increased from 5.3 to 6.6 mg/g db, 2.06 to 3.57 mg GAE/g db and from 3.18 to 4.09 mg QE/g db, respectively. Nevertheless, germination decreased the perception of bitter after-taste, as shown by e-tongue results, probably as a consequence of sugar accumulation, masking the bitter taste. The main effects occurred during the first 48 hours of the process.