The effect of training on the temporal dominance of sensations method: A study with milk protein hydrolysates

The Temporal Dominance of Sensations (TDS) method could be an alternative approach to time-consuming trained panels for the sensory analysis of protein hydrolysates. However, the amount of training required for accurate TDS results with hydrolysates is unclear. In addition, the masking of unpleasant aftertastes in protein hydrolysates using sweeteners is often only partially successful. The aim of this study was: (a) To examine changes in TDS results with hydrolysates as a group of panelists progress through different levels of training: as untrained panelists, familiarized panelists, and trained panelists. (b) To examine the effect of increasing sweetness on the temporal suppression of sensory attributes in hydrolysates. Four products were assessed: a casein hydrolysate at 10% wt/wt with 4 levels of sucralose (0%, 1.5, 3, and 6% equivalent sweetness). Similar TDS results were obtained for all three levels of training for each product, however consensus of selection and product discrimination increased with training. As sweetness increased bitterness was suppressed however cheesiness increased. Sweetness tended to peak before bitterness and cheesiness, however temporal changes were small and subtle. Practical applicationsRunning traditional descriptive trained panels is expensive and time-consuming. It is particularly difficult with protein hydrolysates, as their unpleasant sensory properties mean that panelists are hard to recruit, and will often leave panels during training. This work attempted to understand if the Temporal Dominance of Sensations (TDS) method could be used with untrained panelists for protein hydrolysates. Results suggest a TDS panel of untrained panelists may be suitable for the assessment of hydrolysates, however TDS training still provided the best quality data. This work also represents a first attempt to understand the aftertaste profile of a protein hydrolysate (and attempts to mask aftertaste with a sweet masking agent) using a temporal sensory method. Results showed most sensory attributes dominating during tasting in the mouth declined very slowly after swallowing.