Norris M B, Noble A C, Pangborn R M
Physiol Behav. 1984 Feb;32(2):237-44. doi: 10.1016/0031-9384(84)90136-7.
Twenty subjects recorded perceived sourness of solutions of citric + fumaric and of citric + tartaric acids, at pH 3.5 and titratable acidity (TiA) of 4.0 g/l on a moving chart, while parotid saliva flow was recorded via a sialometer . Sourness intensity and flow were greater when citric was the minor acid than when it was dominant. Subjects varied widely in calculated volume of saliva reservoir, but not flow rate (time to 2/3 reservoir vol.). In tartaric-fumaric acid mixtures varying in pH (3.0-3.75) at a constant TiA of 4.0 g/l, and varying in TiA (3.7-4.6 g/l) at a constant pH of 3.5, sourness intensity and parotid flow increased with acidity and decreased with pH. However, eight subjects with a high flow (HF = 1.2 +/- 0.28 g/2 min) and nine subjects with a low flow (LF = 0.43 +/- 0.11 g/2 min) differed widely: (a) In response to variation in stimulus pH and TiA, HF demonstrated marked alteration in flow, but little change in sourness ; LF responded at a lower absolute level, but showed marked changes in sourness and little change in flow; (b) Salivary pH was higher and Na+ was three times greater for the HF than for the LF subjects; and (c) Salivary Ca++ showed a direct relationship with flow and pH among the HF, but an inverse relationship for the LF subjects.
20名受试者在活动图表上记录了pH值为3.5、可滴定酸度（TiA）为4.0 g/l时，柠檬酸与富马酸混合溶液以及柠檬酸与酒石酸混合溶液的酸味感受，同时通过涎液计记录腮腺唾液流量。当柠檬酸为次要酸时，酸味强度和流量比其占主导时更大。受试者唾液储存库的计算体积差异很大，但流速（达到储存库体积2/3的时间）并无差异。在TiA恒定为4.0 g/l、pH值在3.0 - 3.75之间变化，以及pH值恒定为3.5、TiA在3.7 - 4.6 g/l之间变化的酒石酸 - 富马酸混合物中，酸味强度和腮腺流量随酸度增加而增加，随pH值降低而降低。然而，8名高流量受试者（HF = 1.2 ± 0.28 g/2分钟）和9名低流量受试者（LF = 0.43 ± 0.11 g/2分钟）存在显著差异：（a）对于刺激pH值和TiA的变化，高流量受试者的流量变化显著，但酸味变化不大；低流量受试者的反应绝对水平较低，但酸味变化显著，流量变化不大；（b）高流量受试者的唾液pH值更高，Na⁺含量是低流量受试者的三倍；（c）高流量受试者中唾液Ca²⁺与流量和pH值呈直接关系，而低流量受试者中则呈反比关系。
