Descriptive sensory analysis of copper and iron compounds in water in comparison with psychophysical measurement

Abstract

This study was conducted to establish descriptive sensory analysis procedures and sensory profiles for iron and copper as well as to compare the results obtained from 2 approaches, a psychophysical measurement using a generalized labeled magnitude scale (gLMS) (PLMS) and an applied descriptive analysis using a 15-point categorical scale (DCAT). During DCAT, bitter taste, sour taste, electric sensation, astringency, and rusty nail flavor, as well as aftertastes of bitter taste, rusty nail, and astringency, were developed as descriptors. Copper was characterized by a strong bitter taste and astringency, whereas iron had a strong rusty nail flavor. Both DCAT and PLMS produced similar sensory profiles and relationships between perceived intensity and physical stimuli for iron and copper. However, ratings obtained from PLMS had larger variance than those from DCAT. The practical implications of the larger variance by PLMS should be further examined in future studies.