Gustatory system

The perception of flavor is a fine balance between the sensory input of both desirable and undesirable flavors. It involves a complex series of biochemical and physiological reactions that occur at the cellular and subcellular level (see Chapters 1-3). Final sensory perception or response to the food is regulated by the action and interaction of flavor compounds and their products on two neur networks, the olfactory and gustatory systems or the smell and taste systems, respectively (Figure 1). The major food flavor components involved in the initiation and transduction of the flavor response are the food s lipids, carbohydrates, and proteins, as well as their reaction products. Since proteins and peptides of meat constitute the major chemical components of muscle foods, they will be the major focus of discussion in this chapter. 

The taste sensor will be applicable for quality control in food industry and help automation of the production. The sense of taste is vague and largely depends on subjective factors of human feelings. If we compare the standard index measured by means of the taste sensor with the sensory evaluation, we will be able to assess taste objectively. Moreover, the mechanism of information processing of taste in the brain as well as the reception at taste cells will also be clarified by developing a taste sensor which has output similar to that of the biological gustatory system. 

Dunipace L., Meister S., McNealy C. and Amrein H. (2001) Spatially restricted expression of candidate taste receptors in the Drosophila gustatory system. Curr. Biol. 11, 822-835. 

The inability to taste food is a common complaint when nasal congestion reduces the sense of smell. Thus, smell greatly augments our sense of taste (also known as gustation), and taste is, in many ways, the sister sense to olfaction. Nevertheless, the two senses differ from each other in several important ways. First, we are able to sense several classes of compounds by taste that we are unable to detect by smell salt and sugar have very little odor, yet they are primary stimuli of the gustatory system. Second, whereas we are able to discriminate thousands of odorants, discrimination by taste is much more modest. Five primary tastes are perceived bitter, sweet, sour, salty, and umami (the taste of glutamate from the Japanese word for "deliciousness"). These five tastes serve to classify compounds into potentially... 

As detailed already, the olfactory system conveys odour information initially to the antennal lobe and then further via the projection neurons to the lateral horn and the mushroom bodies. From both these centres, premotor commands are thought to originate. The gustatory system, in contrast, carries sugar information to the suboesophageal ganglion, from where premotor commands likely can be triggered... 

Thus, there is compelling evidence for the existence of a gustatory system devoted to LCFA detection in rodents. Does such a system exist in humans ... 

Finger TE, Morita Y (1985) Two gustatory systems facial and vagal gustatory nuclei have different brainstem connections. Science 227 776-778 Finger TE, Bottger B, Hansen A, Anderson KT, Alimohammadi H, Silver WL (2003) Solitary chemoreceptor cells in the nasal cavity serve as sentinels of respiration. Proc Natl Acad Sci USA 100 8981-8986... 

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