Afrosimetric estimation of threshold saponin concentration for bitterness in quinoa (Chenopodium quinoa Willd)

Taste testings and saponin estimation by a simple afrosimetric method showed that quinoa containing 0·11% saponins or less (corresponding to foam heights of 1·0 cm or less) can be considered sweet. A variation of the standard afrosimetric method is described which reduces total analysis time from 73 to 7 min. Used with the proper precautions, this rapid method, in which quinoa producing foam heights of 1·3 cm or less is considered sweet, is suitable for selecting promising low‐saponin varieties in field trials and for monitoring the efficacy of abrasive dehulling (polishing) as a debittering process.