This study aims to investigate alterations in volatile compounds and chemical components that may affect the sensory properties of Cynanchi wilfordii roasted at 120 °C and 180 °C for various durations of time (0 to 4 min). For volatile compound profiles, tridecane, tetradecane, and ethyl hexyl ether were detected as major compounds of the sample without roasting. As the roasting temperature increased, the types of volatile compounds increased, whereas the content decreased with an increase in heterocyclic compound generation. The sample roasted at 120 °C for 1 min showed a notably different profile pattern from the other roasted samples. For the sniffing test performed by trained panelists using gas chromatography olfactometry, naphthalene and nonanal, which induce spicy and raw C. wilfordii, respectively, were perceived most intensely throughout all the samples. In the electronic tongue analysis, the sample roasting at 180 °C showed an increased and decreased pattern in umami taste and saltiness, respectively, with increased roasting time. Electronic tongue analysis results showed that the sample roasted at 180 °C for 4 min would have the best sensory preference. Along with the volatile compound profiles, the sample roasted at 120 °C for 1 min had more sourness than the other samples, and would potentially have distinctive sensory characteristics. This study should provide baseline data on variations in the sensory properties and industrial applications of C. wilfordii upon roasting. PRACTICAL APPLICATION: Various applications of food ingredients through changes in sensory characteristics by roasting will provide consumers more options for food selections. Accordingly, this study will be utilized by (1) individuals and food companies who are interested in functional foods, (2) individuals and food industries that seek optimum roasting conditions for proper sensory characteristics of foods, and (3) farmers and crop producers who seek for utilization the applications of Cynanchi wilfordii as a food ingredient.
Keywords: Cynanchi wilfordii; E-tongue; roasting; thermal processing; volatile compounds.
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