I recently came across a batch of citric acid, which gave a blackish froth with off odour when it was dissolved in water and liquid glucose at a temperature 70-80 degrees. Can anyone please help to understand the chemistry behind this?
I think if citric acid turns blackish froth then it may char because the impurity of mixture in citric acid means other mono saccharides or disaccharides may affect its appearance. This can further explained by spectroscopy technique.
My question is basically knowing about the degradation of citric acid. there is no charring...and the solution thus obtained is giving a foul smell with blackish appearance.