Short Communication: Influence of Serving Temperature on the Retronasal Thresholds of Two Kokumi Peptides: γ‐Glu‐Phe and γ‐Glu‐Val‐Gly

ABSTRACT Kokumi, prospectively the sixth basic taste, provides mouthfulness, thickness, continuity, and a rich and long‐lasting taste, attributed to several peptides, two of which were previously preliminarily identified as key compounds responsible for kokumi perception in fermented doenjang . The sensory perception is reportedly influenced by the serving temperature of food. Herein, the influence of the serving temperature (4°C, 25°C, and 60°C) on the retronasal thresholds of two kokumi peptides, γ‐Glu‐Phe and γ‐Glu‐Val‐Gly, was evaluated. Seven series of three ascending forced choices (7–3 AFC) were selected for the independently conducted retronasal threshold tests ( n = 20). The best estimate thresholds (BETs) depended on the serving temperature, differing for γ‐Glu‐Phe ( p < 0.05), but were temperature‐insensitive for γ‐Glu‐Val‐Gly. For γ‐Glu‐Phe, the BET at 4°C was significantly lower than that at 25°C, suggesting that kokumi perception derived from γ‐Glu‐Phe is better recognized at 4°C than at other temperatures.