Flavor mystery of spicy hot pot base: Chemical understanding of pungent, numbing, umami and fragrant characteristics

Spicy hot pot (SHP) is a regional Chinese food and popular global cuisine. The various spices in the SHP base serve as the main source of unique flavor in SHP. However, there is currently a dearth of molecular understanding of the typical flavor characteristics (pungent, numbing, umami, and fragrant) in SHP base, which restricts the elucidation of flavor formation mechanism in SHP. The present review provides a comprehensive analysis of SHP base based on a multidisciplinary intersection. This review focuses on the components responsible for pungent, numbing, umami, and fragrant characteristics in the SHP base. Furthermore, the main flavor compounds and their formation mechanisms are systematically reviewed. In addition, multisensory interactions and evaluation of flavor attributes are summarized and discussed. Capsaicinoids are considered the primary pungent compounds, and their perception is related to TRPV1 receptor. Sanshool and its derivatives are the primary basis of numbing sensation, while the sensation of taste-active compounds is related to TRPA1/TRPV1 and KCNK3/KCNK9/KCNK18 receptors. Amino acids, nucleotides, and umami/umami-enhancing peptides are significant sources of umami taste in SHP base. T1R1/T1R3 and mGlu4 are suggested to be associated with umami perception. The aroma compounds of SHP base are mainly generated by lipids/fatty acids and spices in SHP base. Sensory evaluation, electronic noses and tongues, and taste biosensors contribute to further understanding the flavor perception in SHP base. Overall, the present review can provide a theoretical reference for an understanding of flavor mystery of the SHP base.