In this study, we investigated the characteristics of three types of eggs (normal, vitamin D (VD) enriched, and docosahexaenoic acid (DHA) enriched) by sensory evaluation, complemented with a taste sensing system. Additionally, the viscoelasticity and chromaticity of the egg yolks were evaluated and the concentration of free amino acids was measured. The dynamic viscoelasticity and free amino acid concentration did not vary significantly in the three types of eggs evaluated. However, the difference in each egg was highlighted in the chromaticity of the egg york. The “saltiness” and “bitterness (initial taste),” but not the “richness” of each egg, could be recognized by the taste sensing system. Contrastingly, in the sensory evaluation, VD- and DHA-enriched eggs scored higher in terms of egg yolk chromaticity, umami, and richness in taste compared to normal eggs. The findings of the taste sensing system did not necessarily correlate with those of the sensory evaluation. However, “saltiness” and “bitterness (initial taste),” which could not be distinguished by sensory evaluation, were recognized by the taste sensing system.

Investigation of the effect of aroma on the taste characteristics of three bitter chocolates, formulated from different cacao bean varieties (harvested from Ghana, Venezuela, and Ecuador). Sensory evaluations were given scores by 95 panelists wearing or not wearing nose clips. A questionnaire survey was also carried out. Twenty-six panelists showed changed preferences for chocolate in sensory tests while wearing a nose clip using the TDS (Temporal Dominance of Sensations) method. The scoring results showed the sensation of taste to be more sensitive when not wearing a nose clip than when wearing one, and that greater taste intensity was experienced without a nose clip. The TDS method revealed the key aroma characteristics: the Ghanaian chocolate had a “sweet nut” and “honey” taste, the Venezuelan variety had a “roasted nuts” flavor, and the Ecuadorian variety had as “floral” and “fruity” taste.

The questionnaire survey showed the most important item to be “Taste” (80.0％), followed by “Aroma”. The fact that 49.5％ of subjects showed different preferences for chocolate types while wearing the nose clip demonstrates that the aroma of chocolates affects taste preference. Aroma is therefore an important characteristic in the sensory evaluation of chocolate.