Differences in Gustatory Thresholds for NaCl between Two Methods.

Abstract

Detection and recognition thresholds for the taste of salt (NaCI) were determined using two different methods in eight young females (age 21 ~ 25). The methods employed were (1) a forced choice of three stimulus drop technique and (2) a paired comparison forced choice sipping technique. 1) Detection and recognition thresholds (geometric mean and its standard deviation) determined by the three stimulus drop technique were 10.3 (2.8) and 28.6 (1.9) mmol/1, and those determined by the sipping technique were 4.9 (2.5) and 16.0 (1.7) mmol/l respectively. Both threshold values determined by the sipping technique were lower than those determined by the three stimulus drop technique. 2) There was no significant variation in threshold values attributable to the time of measurement in a day. 3) Inter-individual variation of the threshold values was significant. Spearman rank correlation coefficients between the two methods were rs=0.92 (p <0.01) in respect of the detection threshold and rs=0.90 (p<0.01)in respect of the recognition threshold. Regression equation between the two methods was y=1.0x- 0.3 (x, the log-converted values by the three stimulus drop technique ; y, the log-converted values by the sipping technique) . This equation was applicable both to the detection and recognition thresholds. 4) There were no significant difference in the coefficients of variation of thresholds between the two methods. Jpn.