Abstract: Sweetness is an important driver for food intake and one of the most popular taste sensations. At present, there is a preliminary understanding of the signaling pathways of sweetness and the mechanisms that affect sweetness sensation. Human sweetness sensation is expressed through at least two types of signaling pathways, one of which is mediated by heterodimers formed by the taste receptor family 1 member 2 (T1R2) and the taste receptor family 1 member 3 (T1R3), whereas the other by sodium glucose co-transporters (SGLT) and glucose transporters (GLUT). This article reviews the structure of T1R2/T1R3 heterodimer and the mechanism of sweet signal transduction, and discusses the effects of internal and external factors such as bitterness, sourness, umami, anti-sweetness substances, aroma compounds, saliva, obesity and age on sweetness sensation. The shortcomings of the current research are presented, such as little effect of the current available noncaloric sweeteners (NCSs) in attenuating obesity and diabetes, few studies on the interactions of sweet taste with the other four taste sensations, unclear understanding of the molecular basis of the regulation mechanisms of anti-sweetness substances at the receptor level, and limitations of using rodents as an experimental substitute for humans in sweet taste research. This article aims to understand how sweet substances exert their functions in complex food matrices, hoping to provide theoretical support and ideas for future development and application of NCS-containing foods.

Key words: sweet signals; noncaloric sweeteners; impact mechanism; taste regulation