Application of the dual attribute time-intensity (DATI) sensory method to the temporal measurement of bitterness and astringency in sorghum

Abstract

Bitterness and astringency are attributes generally cited as the cause of tannin sorghums being unpalatable. The objective here was to determine the effect of sorghums with varying tannin content on bitterness and astringency simultaneously using dual attribute time-intensity (DATI). A trained panel assessed bitterness and astringency of bran infusions of tannin and tannin-free sorghums. In both sorghum types, bitterness developed and reached maximum intensity faster (Tmax 22.5 s; P < 0.001) than astringency (27.9 s). The duration of the astringent sensation (Dtot 69.9 s) lasted longer than bitterness (66.3 s). Overall, the temporal parameters for bitterness distinguished infusions from tannin and tannin-free sorghums slightly more clearly than those for astringency. The research established that, for sorghum, bitterness and astringency are related. The DATI method also revealed that panellists’ perceptions of the time course of bitterness and astringency differ.