Gluconic acid effect

Gluconic acid and other hydroxy acids act similarly. Sequestering agents are used extensively, e.g. for preventing deleterious catalytic effects of traces of Fe or Cu and in analysis. 

Most divalent and trivalent ions, with the exception of the alkaline-earth metals, are effectively chelated by the hydroxycarboxylates citric and tartaric acid, and citric acid will also sequester iron in the presence of ammonia. Another hydroxycarboxylate, gluconic acid, is especially useful in caustic soda solution and as a general-purpose sequestering agent. 

The pH and the concentration of calcium in milk also vary, with consequential effects on the properties of renneted milk gels. The addition of CaCl2 to cheesemilk (0.02%) is widely practised and adjustment and standardization of milk pH by using the acidogen, gluconic acid-5-lactone (GDL), is recommended and commercially practised on a limited scale. 

The second procedure, and probably the more effective [if, as here, the desired product is L-xy/o-2-hexulosonic acid (28)], is based on simultaneous, fermentative oxidation of L-idonic acid (42) to 28, and fermentative decomposition of D-gluconic acid (86). Efforts directed toward the simultaneous oxidation of 42 and decomposition of D-gluconic acid will be summarized, as well as efforts made to convert 42 efficiently into 28 by fermentative oxidation. 

The biosensor was used for the analysis of gluconic acid in honey samples. No matrix effect was observed and, therefore, the determination was carried out by interpolation of the corresponding amperometric responses into an appropriate calibration graph. 

Matzerath, I., W. Klaui, R. Klasen, and H. Sahm. 1995. Vanadate catalyzed oxidation of 5-keto-D-gluconic acid to tartaric acid The unexpected effect of phosphate and carbonate on rate and selectivity. Inorg. Chim. Acta 237 203-205. 

Peinado, R. A., Moreno, J. J., Ortega, J. M., and Mauricio, J. C. (2003). Effect of gluconic acid consumption during simulation of biological aging of sherry wines by a flor yeast strain on the final volatile compounds. ]. Agric. Food Chem. 51, 6198-6203. 

Peinado, R.A., Mauricio, J.C., Medina, M., Moreno, J. (2004b). Effect of Schizosaccharomyces pombe on aromatic compounds in dry sherry wines containing high level of gluconic acid. J. Agric. Food Chem., 52, 4529-4534. 

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