Sprouting of quinoa (Chenopodium quinoa Willd.) : Effect on saponin content and relation to the taste and astringency assessed by electronic tongue

This study aimed at addressing the effect of quinoa sprouting on saponins which are considered the main responsible for quinoa bitterness and astringency, and consequently on quinoa taste. Whole quinoa was sprouted for 12, 24, 48, and 72 h at 22 °C and dried at 55 °C for 6 h. Quinoa taste was assessed by electronic tongue and mainly related to the amount of saponins that were evaluated by thin layer chromatography (TLC) and mass spectrometry (MS). Sprouting decreased quinoa bitterness and astringency, with the main changes occurring within the 48 h of treatment. Both semi-quantitative (by TLC) and quantitative (by MS) analysis revealed that changes in quinoa taste upon sprouting was mainly related to the decrease in the amount of saponins, reaching the value of 0.086 mg/100 g after 48 h of treatment. Finally, changes in phenolic compounds seem to play a minor role in affecting the taste traits of sprouted quinoa.