Maleic acid and succinic acid in fermented alcoholic beverages are the stimulants of gastric acid secretion

Alcoholic beverages produced by fermentation (e.g., beer and wine) are powe rful stimulants of gastric acid output and gastrin release in humans. The a im of this study was to separate and specify the gastric acid stimulatory i ngredients in alcoholic beverages produced by fermentation. Yeast-fermented glucose was used as a simple model of fermented alcoholic beverages;it was stepwise separated by different methods of liquid chromatography, and each separated solution was tested in human volunteers for its stimulatory acti on on gastric acid output and gastrin release. Five substances were detecte d by high-performance liquid chromatography and were analyzed by mass spect rometry and 1H-13C nuclear magnetic resonance spectroscopy. At the end of t he separation process of the five identified substances, only the two dicar boxylic acids, maleic acid and succinic acid, had a significant (P < 0.05) stimulatory action on gastric acid output (76% and 70% of fermented glucose , respectively), but not on gastrin release. When given together, they incr eased gastric acid output by 100% of fermented glucose and by 95% of maxima l acid output. We therefore conclude that maleic acid and succinic acid are the powerful stimulants of gastric acid output in fermented glucose and al coholic beverages produced by fermentation, and that gastrin is not their m ediator of action.