Harmon Caroline Payton, Ahmed Osama M, Breslin Paul A S
Rutgers University, New Brunswick, New Jersey 08901, United States.
University of Washington, Seattle, Washington 98195, United States.
J Agric Food Chem. 2024 Oct 1. doi: 10.1021/acs.jafc.4c05281.
Amino acids are necessary for life, and many must be consumed because they cannot be endogenously synthesized. Typically, we eat them as proteins and peptides, which have little taste. However, we also directly ingest free amino acids, several of which are aversive because they elicit bitterness. This bitterness often prevents many patient populations from taking formulas and supplements containing free amino acids. Here, we characterize which amino acids are the most bitter, their concentration-intensity functions, and individual differences in bitterness perception, and we explore how sodium salts suppress the bitterness of amino acids. We found that the essential amino acids comprise the most bitter stimuli, with six of them conveying the most bitterness. Clustering and correlating amino acids by individual differences in bitterness perception show that there are approximately four groupings of amino acids and suggest that within these clusters, amino acids may be activating the same or overlapping TAS2Rs. We also show that bitterness can be largely suppressed by sodium salts for 5 of the 6 most bitter amino acids. These results hold promise for managing the bitter taste of nutritional supplements that contain amino acids and improving compliance.
氨基酸是生命所必需的，许多氨基酸必须通过摄入获得，因为它们无法在体内合成。通常，我们通过蛋白质和肽来摄取氨基酸，而蛋白质和肽几乎没有味道。然而，我们也会直接摄入游离氨基酸，其中有几种会引发苦味，让人厌恶。这种苦味常常使许多患者群体不愿服用含有游离氨基酸的配方产品和补充剂。在此，我们确定了哪些氨基酸苦味最强、它们的浓度 - 强度函数以及苦味感知的个体差异，并探讨了钠盐如何抑制氨基酸的苦味。我们发现必需氨基酸构成了苦味最强的刺激物，其中六种氨基酸苦味最为突出。通过苦味感知的个体差异对氨基酸进行聚类和关联分析表明，氨基酸大约可分为四类，这表明在这些类别中，氨基酸可能激活了相同或重叠的味觉受体2型（TAS2Rs）。我们还表明，对于六种苦味最强的氨基酸中的五种，钠盐可在很大程度上抑制其苦味。这些结果有望解决含氨基酸营养补充剂的苦味问题，并提高顺应性。
