Mela D J
Monell Chemical Senses Center, Philadelphia, PA 19104.
Pharmacol Biochem Behav. 1989 Nov;34(3):483-5. doi: 10.1016/0091-3057(89)90544-3.
It has been reported that prolonged application of 10 micromolar (microM) caffeine (CAF) to the dorsal surface of the tongue may markedly enhance the perceived intensity of many taste stimuli, including NaCl and several noncarbohydrate sweeteners. The present study investigated the effect of oral CAF vs. placebo ingestion on perceived taste intensity. Ingestion of CAF (5.5 mg/kg) raised median salivary CAF levels to 19.8 microM at 50 minutes post-dose, when subjects evaluated the intensity of solutions of 5 noncarbohydrate sweeteners, 2 carbohydrate sweeteners, 2 bitter tastants, NaCl, citric acid, 2 odors, and a tone. Taste solutions were prepared using either 1) deionized water or 2) 10 microM CAF as the medium, and all stimuli were rated for intensity on a 9-point category scale. There was no effect of condition (CAF or placebo) or tastant medium on any response measure. The results suggest that perceptions of taste intensity are not appreciably altered under natural conditions of CAF ingestion and subsequent lingual adaptation to microM levels of CAF in saliva.
据报道，将10微摩尔（μM）咖啡因（CAF）长时间应用于舌背可能会显著增强许多味觉刺激的感知强度，包括氯化钠和几种非碳水化合物甜味剂。本研究调查了口服CAF与摄入安慰剂对味觉强度感知的影响。当受试者评估5种非碳水化合物甜味剂、2种碳水化合物甜味剂、2种苦味剂、氯化钠、柠檬酸、2种气味和一种音调溶液的强度时，摄入CAF（5.5毫克/千克）使给药后50分钟时唾液中CAF的中位数水平升至19.8微摩尔。味觉溶液使用1）去离子水或2）10微摩尔CAF作为介质制备，所有刺激物均在9点分类量表上对强度进行评分。条件（CAF或安慰剂）或味觉剂介质对任何反应指标均无影响。结果表明，在摄入CAF以及随后舌部适应唾液中微摩尔水平CAF的自然条件下，味觉强度的感知没有明显改变。
