Lapis Trina J, Penner Michael H, Lim Juyun
Department of Food Science and Technology, Oregon State University, Corvallis, OR 97331, USA.
Department of Food Science and Technology, Oregon State University, Corvallis, OR 97331, USA
Chem Senses. 2014 Nov;39(9):737-47. doi: 10.1093/chemse/bju031.
The sense of taste is essential for identifying potential nutrients and poisons. Accordingly, specialized taste receptor cells are activated by food-derived chemicals. Because of its importance in the human diet, oral detection of starch, or its degradation products, would presumably be highly beneficial. Yet, it has long been assumed that simple sugars are the only class of carbohydrates that humans can taste. There is, however, considerable evidence that rodents can taste starch degradation products (i.e., glucose polymers composed of maltooligosaccharides with 3-10 glucose units and maltopolysaccharides with >10 glucose units) and that their detection is independent of the sweet taste receptor, T1R2/T1R3. The present study was designed 1) to measure individual differences in human taste perception of glucose polymers, 2) to understand individual differences in the activity of salivary α-amylase, and 3) to investigate the role that salivary α-amylase may play in the taste perception of glucose polymers. In the first experiment, subjects rated taste intensity of glucose, sucrose, NaCl, and glucose polymers of various chain lengths, while their noses were clamped. Saliva samples from the subjects were also collected and their salivary α-amylase activity was assayed. Results showed that the perceived intensities of glucose, sucrose, and NaCl were significantly correlated (r = 0.75-0.85, P < 0.001), but not with the longer chain glucose polymers, whereas intensity ratings of all glucose polymers were highly correlated with one another (r = 0.69-0.82, P < 0.001). Importantly, despite large individual differences in α-amylase activity among subjects, responsiveness to glucose polymers did not significantly differ between individuals with high and low α-amylase activity. A follow up experiment was conducted to quantify the concentrations of glucose and maltose that were inherently present in the glucose polymer stimuli and to determine whether the amounts were within a perceptually detectable range. Results revealed that the amounts of simple sugars present in the test stimuli were trivial and were mostly at an undetectable level. These data together provide strong evidence that humans can taste glucose polymers and that the responsiveness to glucose polymers is independent of that to simple sugars.
味觉对于识别潜在的营养物质和毒素至关重要。因此，专门的味觉受体细胞会被食物中的化学物质激活。鉴于其在人类饮食中的重要性，口腔对淀粉或其降解产物的检测可能会带来极大益处。然而，长期以来人们一直认为单糖是人类唯一能尝出味道的碳水化合物类别。不过，有大量证据表明啮齿动物能够尝出淀粉降解产物（即由3 - 10个葡萄糖单位的麦芽寡糖和超过10个葡萄糖单位的麦芽多糖组成的葡萄糖聚合物），并且它们的检测独立于甜味受体T1R2/T1R3。本研究旨在：1）测量人类对葡萄糖聚合物味觉感知的个体差异；2）了解唾液α - 淀粉酶活性的个体差异；3）探究唾液α - 淀粉酶在葡萄糖聚合物味觉感知中可能发挥的作用。在第一个实验中，受试者在鼻子被夹住的情况下对葡萄糖、蔗糖、氯化钠以及不同链长的葡萄糖聚合物的味道强度进行评分。同时收集受试者的唾液样本并检测其唾液α - 淀粉酶活性。结果显示，葡萄糖、蔗糖和氯化钠的感知强度显著相关（r = 0.75 - 0.85，P < 0.001），但与较长链的葡萄糖聚合物无关，而所有葡萄糖聚合物的强度评分彼此高度相关（r = 0.69 - 0.82，P < 0.001）。重要的是，尽管受试者之间的α - 淀粉酶活性存在很大个体差异，但高α - 淀粉酶活性个体和低α - 淀粉酶活性个体对葡萄糖聚合物的反应性并无显著差异。进行了后续实验以量化葡萄糖聚合物刺激物中固有存在的葡萄糖和麦芽糖的浓度，并确定这些量是否在可感知的范围内。结果表明，测试刺激物中存在的单糖量极少，大多处于无法检测的水平。这些数据共同提供了有力证据，证明人类能够尝出葡萄糖聚合物，并且对葡萄糖聚合物的反应性独立于对单糖的反应性。
