Taste of Fat: A Sixth Taste Modality?

Abstract

An attraction for palatable foods rich in lipids is shared by rodents and humans. Over the last decade, the mechanisms responsible for this specific eating behavior have been actively studied, and compelling evidence implicates a taste component in the orosensory detection of dietary lipids [i.e., long-chain fatty acids (LCFA)], in addition to textural, olfactory, and postingestive cues. The interactions between LCFA and specific receptors in taste bud cells (TBC) elicit physiological changes that affect both food intake and digestive functions. After a short overview of the gustatory pathway, this review brings together the key findings consistent with the existence of a sixth taste modality devoted to the perception of lipids. The main steps leading to this new paradigm (i.e., chemoreception of LCFA in TBC, cell signaling cascade, transfer of lipid signals throughout the gustatory nervous pathway, and their physiological consequences) will be critically analyzed. The limitations to this concept will also be discussed in the light of our current knowledge of the sense of taste. Finally, we will analyze the recent literature on obesity-related dysfunctions in the orosensory detection of lipids ("fatty" taste?), in relation to the overconsumption of fat-rich foods and the associated health risks.

Does eating good-tasting food influence body weight?

“…The attraction of sucralose is its sweet taste; preferences for sucralose solutions are absent in mice with genetic ablation of molecular components of the sweet taste transduction cascade [e.g., (11,40)]. It is less clear why mice are attracted to mineral oil; its primary orosensory property, at least to humans, is oiliness (a texture); it may also have a greasy (16) or fatty taste [reviews (6,17,21) but see (33,42)], and it has an odor to rats (14). Our work with sucralose and mineral oil suggests that Naim et al's (26) findings cannot be discounted because the flavors they used did not stimulate taste or texture.…”

Alteration in Taste Perception in Cancer: Causes and Strategies of Treatment

“…The fourth type of taste cells are termed as type IV cells which are basal, non-polarized, presumably undifferentiated cells and serve as progenitor cells for other three types of taste cells (Miura et al, 2006). The comprehensive reviews on different taste modalities and the activation of different brain areas can be consulted elsewhere (Bermúdez-Rattoni, 2004; Chaudhari and Roper, 2010; Roper, 2013; Besnard et al, 2016). However, in brief, we would like to outline the implication of TRCs in different taste perception.…”

Fatty acid taste quality information via GPR120 in the anterior tongue of mice

“…22,23 However, the expression level of CD36 in fungiform papillae was nine times lower than that of circumvallate papillae in mice. 26,27 When assessors participated in sensory training sessions for at least 2 years, "fatty" and irritant "scratchy" taste components of long-chain fatty acids were discriminated. 24,25 Indeed, fatty acids do not seem to impart an easily identifiable sensation in untrained subjects.…”