Detection of Spicy Compounds Using the Electronic Tongue

Area of Science:

• Food Science and Technology
• Sensory Science
• Analytical Chemistry

Background:

• Increasing global demand for spicy food products necessitates efficient analytical methods.
• Traditional sensory evaluation of spicy foods faces challenges due to trigeminal stimulation and sensory fatigue.
• Objective and rapid analytical techniques are needed for routine spice evaluation.

Purpose of the Study:

• To assess the capability of an electronic tongue (e-tongue) in distinguishing between various spicy compounds.
• To evaluate the e-tongue's performance in differentiating varying concentrations of selected spicy compounds.
• To validate e-tongue findings with human sensory perception.

Main Methods:

• Seven distinct spicy compounds (capsaicin, thymol, piperine, zingerone, p-cymene, menthol, eugenol) were analyzed.
• The e-tongue was employed to analyze low, medium, and high concentrations of each compound.
• Sensor response data were analyzed using clustering techniques, followed by same-different sensory testing with 80 untrained consumers.

Main Results:

• The e-tongue successfully discriminated among different concentrations of spicy compounds, achieving discrimination indices between 72% and 84%.
• E-tongue sensor data resulted in three distinct clusters, grouping compounds with similar sensory profiles (e.g., menthol/eugenol/p-cymene, capsaicin/thymol, piperine/zingerone).
• Human sensory testing confirmed the e-tongue's clustering, with participants distinguishing between the representative samples from each cluster.

Conclusions:

• The electronic tongue demonstrates significant potential as a tool for the objective and rapid evaluation of spicy compounds.
• E-tongue analysis can effectively differentiate between various spicy compounds and their concentrations, complementing or replacing traditional sensory panels.
• This technology offers a practical application for quality control and product development in the expanding spicy food industry, mitigating sensory fatigue.