Touch and Taste in Food Flavor Perception

All beings that inhabit the earth possess incredible abilities to use their senses to perceive sensations that can be considered good or bad. Sensitivities to high and low temperatures, mechanical pressure, irritation, or pain can be perceived by the different layers of the epithelium, and the intensities of these stimuli can directly suggest acceptance or rejection.

Rolls (2016) describes how somatosensory stimuli, such as tactile stimuli represented by thermoception, mechanoception, or nociception (which are the receptors for painful sensations), are reflected in the orbitofrontal cortex and pregenual anterior cingulate cortex, as are other stimuli such as taste, olfactory, and visual stimuli (Spence, 2015). The orbitofrontal cortex is more closely linked to affective aspects, which can be mediated by afferent C fibers, which are slightly more intense in the forearm (where these fibers originate) than in the hairless skin, which is represented by the skin of the hands and lacks hair follicles. In the mouth, the orbitofrontal cortex, the pregenual cingulate cortex, and also the singular gustatory cortex are stimulated, demonstrating that the senses of touch and taste are closely linked when we taste food (Rolls, 2016).

Within these aspects, we can use examples such as accepting ice cream if it is cold and creamy; accepting or rejecting spicy Mexican tacos—perceptions that depend on familiarity with these senses, which directly activate nociceptors. Furthermore, before being placed in the mouth, food can be touched to assess its softness, such as that of cheese, for example. When touched to the mouth, this same cheese can provide a sensation reminiscent of the same mechanical stimulus—that is, softness, perceived by the hands. Combined with the aromas of the ripening process and basic flavors, such as intense saltiness, umami, and the sensation of fat, it can provide unparalleled pleasure.

Thus, it is suggested that touch can be considered another sense related to affectivity and emotion. For example, its sensitivity in the mouth can also demonstrate how important these cues are for the palatability and reward of a food, in addition to its influence on the different modulations of appetite (Spence, 2015; Rolls, 2016). It is also recognized that the perception of food flavor is complex and depends on all human senses. Touch, the “deepest” sense, according to the thinker Diderot (1713-1784), can be constantly portrayed alongside the pleasure provided by the most diverse experiences.