So is anyone able help me out with identifying what reaction occurs between Gluconic acid C6H12O7, water and Sulfamic acid H3NSO. Gluconic acid is a slightly yellow color on its own and sulfamic is clear when mixed with water. I mixed small amounts together and over the course of 48 hours the solution gradually darkened to a color similar to an iodine halide. The pH has remained the same over time.
Proportions used were 100g Gluconic acid 25 g DI water and 5 grams sulfamic acid initial pH .98