Sensory responses with smell

As humans, we have developed five perceptive senses smell, taste, touch, sight, and hearing. Sensory response is a good example of adaptation at the molecular level and for this we shall examine the potential of the first two. Odor, like taste, is related to a direct contact of molecules with the olfactive (or gustative) epithelium. These membranes or surfaces contain chemo-receptors which upon excitation by a stimulant give characteristic organoleptic sensations. The specific interactions between small molecules and receptors involve an equilibrium between absorption and desorption and can be studied by chemists using models. 

Human responses to sensory stimulation with liquids introduced into the oral cavity have been compared with orthonasal (smelling via the anterior nares) olfactory judgments in a number of studies (e.g., [22 27]). Interactions between the oral liquids and orthonasal odorants were often... 

Crude efforts were made to assess the effect of the removal of the maxillary palps and maxillae, both accessory mouth parts with many receptors assumed to be connected with the senses of taste or smell. The results were inconclusive, since insects so operated on refused to feed on either treated or untreated leaves, although this could also be interpreted to indicate that 24,055 had the same effect as removal of the sensory receptors—that is, it inhibited the response of the receptors so that the insect failed to recognize the treated material as food. 

Only TEEL approach defines the level of 0, but only with small explanation. Nowadays, the AEGL commission is developing an approach for defining the level of clear sensory perception. At this level there is no discomfort (smell is not problematic), nevertheless exposed population can notice that something happened, which can be a cause of worry and possible further panic. This level can be important for the response to hazard (safety actions). In some cases, the effects on hmnan health appeared before the identification of smell. Hence, for certain substances, this value will be more efficient for better estimation of given situation. The value of detection has also a certain importance for communication needs. 

Sensory assessment is a scientific discipline used to evoke, measure, analyze, and interpret responses to those properties of a substance (food or beverage) that are perceived by the five human senses sight, smell, taste, touch, and hearing. Even though individual judgments are subjective, the techniques of sensory evaluation use objective scientific testing methods principally based on working with a panel of assessors. Two types of analytical objective tests can be observed (1) The discriminative tests is there a difference between several products (2) The... 

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