Nayak A, Carpenter G H
Salivary Research Unit, King's College London Dental Institute, Guy's Hospital, London, SE1 9RT, United Kingdom.
Physiol Behav. 2008 Oct 20;95(3):290-4. doi: 10.1016/j.physbeh.2008.05.023. Epub 2008 Jun 5.
The mechanism by which solutions containing polyphenols are perceived as astringent is not clearly understood. Salivary proline-rich proteins and histatins are products of salivary glands and rapidly bind polyphenols - thought to be the main astringent compound in such as tea and wine. However it is unclear how this interaction leads to the altered oral mouthfeel known as astringency which is characterised by a dry, puckered feeling all around the mouth. To determine the role of saliva in the perception of astringency a protocol was used to decrease the volume of saliva from the mouth (by washing with water) and then by chewing to increase the volume of saliva above resting levels. Following each of these conditions subjects tasted the same solution of black tea and were asked to rate the relative astringency. Compared to the astringency rating of black tea at rest the majority of subjects (10 out of 15) perceived an increase in astringency following washing the mouth with water. Most subjects then perceived a decrease in astringency following chewing compared to the previous state. In all subjects a reduction in salivary proteins was detected following water washout and an increase above resting levels detected following chewing although there was no change in oral mucosal wetness. A separate experiment revealed several of the proteins interacting following the water washout were salivary in origin. We conclude that salivary proteins in solution inhibit the mouthfeeling of astringency which is mediated, at least in part, by salivary proteins adhered to buccal mucosal cells.
含有多酚的溶液被感知为具有涩味的机制尚不清楚。富含脯氨酸的唾液蛋白和组蛋白是唾液腺的产物，能迅速结合多酚，多酚被认为是茶和葡萄酒等饮品中主要的涩味化合物。然而，目前尚不清楚这种相互作用是如何导致口腔口感改变，即产生被称为涩味的那种口腔周围干燥、起皱的感觉。为了确定唾液在涩味感知中的作用，采用了一种方案来减少口腔中的唾液量（通过用水冲洗），然后通过咀嚼使唾液量增加到高于静息水平。在每种情况下，受试者品尝相同的红茶溶液，并被要求对相对涩味进行评分。与静息状态下红茶的涩味评分相比，大多数受试者（15人中有10人）在用水漱口后感觉到涩味增加。与之前的状态相比，大多数受试者在咀嚼后感觉到涩味降低。在所有受试者中，水洗后检测到唾液蛋白减少，咀嚼后检测到唾液蛋白增加到高于静息水平，尽管口腔黏膜湿度没有变化。一项单独的实验表明，水洗后相互作用的几种蛋白质起源于唾液。我们得出结论，溶液中的唾液蛋白抑制涩味的口感，这种抑制至少部分是由附着在颊黏膜细胞上的唾液蛋白介导的。
