Sweetness inducers miraculin

Enhancers and Inducers. A sweetness enhancer is defined as a compound that imparts no taste per se, but when combined with a sweetener in small quantities, increases sweetness intensity. A tme sweetness enhancer has yet to be found. However, a good sweetness inducer, miraculin [143403-94-5] or [125267-18-7] (124), is known. Miraculin is a glycoprotein found in the fmit (called Miracle Fmit) of a West African shmb, chardella dulcifica. By itself, miraculin imparts no sweetness. When activated in the mouth by acidic substances, however, a sucrose-like sweetness is perceived. Thus, sour lemon, lime, grapefmit, rhubarb, and strawberry taste sweet when combined with miraculin. The taste conversion effect can last an hour or longer. 

In 1974, a petition for affiimation of the GRAS status of miracle fmit was submitted by the Miralin Company, mainly based on the fact that miracle fmits have been consumed by humans since before 1958. In 1977, the petition was denied by the FDA. However, miraculin remains a research curiosity. Its stmcture was elucidated in 1989 (125). Another protein, curculin [151404-13-6] (126), has also been reported to exert a sweet-inducing activity similar to miraculin. 

The detailed mechanism of its taste-inducing behavior is still unknown. It has been suggested that the miraculin molecule can change the structure of taste cells on the tongue. As a result, the sweet receptors are activated by acids, which are sour in general. This effect remains until the taste buds return to normal. 

Curculin is a sweet protein (/sac, g (6.8) = 550) of known sequence (Table 8.6). It occurs in the fruit of Curculigo latifolia. The sweet taste induced by this protein disappears after a few minutes, only to reappear with the same intensity on rinsing with water. It is assumed that Ca and/or Mg ions in the saliva suppress the sweet taste. Rinsing with citric acid (0.02mol/l) considerably enhances the impression of sweetness (/sac, g(12) = 970). Thus, like miraculin, curculin acts as a taste modifier. 

---