Rogers P J, Blundell J E
Psychology Department, University of Leeds, UK.
Physiol Behav. 1990 Dec;48(6):801-4. doi: 10.1016/0031-9384(90)90230-2.
Subjects consumed soup (beef consomme) preloads of a fixed size containing different concentrations of monosodium L-glutamate (MSG). Effects on appetite following these preloads, and when no soup was consumed, were assessed in 3 studies. The soups supplemented with MSG were rated as more "pleasant," more "savoury" and more "satisfying" than soup with no added MSG. Compared with the no preload condition, consumption of the soups initially reduced appetitive motivational ratings and increased fullness ratings, but did not alter food intake in a test meal begun either 2 or 30 minutes later. This immediate inhibition of subjective motivation to eat was unaffected by MSG concentration. The failure of the soups to reduce subsequent food intake is presumably due to their low energy content (less than 10 kcal) and indicates that sensory stimulation alone is insufficient to reduce appetite. Indeed, the most important finding concerning MSG showed that motivation to eat recovered more rapidly following a lunchtime meal in which MSG-supplemented soup was served as the first course (compared both with the effect of unsupplemented soup and no preload). It is suggested tentatively that MSG through its stimulation of orosensory receptors and/or by improving the palatability of the soup may have influenced the metabolic disposal of nutrients consumed in the previous meal.
受试者食用了固定分量、含有不同浓度L-谷氨酸钠（味精）的汤品（牛肉清汤）预负荷。在3项研究中评估了这些预负荷以及未食用汤品时对食欲的影响。添加了味精的汤品比未添加味精的汤品被评为更“美味”、更“可口”和更“令人满足”。与无预负荷的情况相比，食用汤品最初会降低食欲动机评分并提高饱腹感评分，但在2分钟或30分钟后开始的测试餐中不会改变食物摄入量。这种对进食主观动机的即时抑制不受味精浓度的影响。汤品未能减少后续食物摄入量可能是由于其低能量含量（低于10千卡），这表明仅靠感官刺激不足以降低食欲。事实上，关于味精的最重要发现是，在午餐时将添加味精的汤品作为第一道菜后，进食动机恢复得更快（与未添加汤品和无预负荷的效果相比）。初步认为，味精通过刺激口部感觉受体和/或改善汤品的适口性，可能影响了上一餐所摄入营养物质的代谢处理。
