A zinc protein from parotid saliva has been isolated and purified to apparent homogeneity from human subjects with normal taste acuity by gel filtration and ion exchange chromatography. The protein has a molecular weight of 37,000 and does not appear to have subunits. It is composed of 8% histidine residues and has 2 moles of zinc per mole of protein. Radioactive sugars have been demonstrated to bind in a specific manner to membranes isolated from taste buds from bovine circumvallate papillae but not to non-taste bud bearing membranes from epithelial tissue surrounding these papillae. Miraculin, a glycoprotein from the plant Synsepalum dulcificum has been studied. The sugars in the glycoprotein have been determined to be xylose, fucose, galactose and mannose. Its activity not only relates to a sweetness provoking effect but also to a sourness and bitterness blocking effect. The clinical pathophysiological characteristics of patients with post influenzal hypogeusia and hyposmia have been evaluated and noted. They commonly exhibit Rudolph Sign and upon biopsy of the nasal mucous membrane exhibit chronic inflammation in the upper lamina propria. A double blind study of the effects of zinc sulfate and of placebo in a group of 106 unselected patients with taste and smell dysfunction was carried out. The results indicated placebo and zinc sulfate were effectively equivalent in the treatment of these disorders although abnormalities of zinc metabolism could be demonstrated in the patients. Acetylcholinesterase has been found in the pore region of the taste buds from circumvallate papillae of rats. This observation supports earlier concepts that the cholinergic nervous system plays an important role in the taste process. A contractile mechanism has been described in the taste bud of fungiform papillae of the mouse; contraction of a bundle of tonofilaments which resides in the Type II cells of the taste bud may be vehicle for this mechanism.