[ketchito]

Hi Nilesh. I had the same issue with a floor cleaner some time ago. The problem with neutralizing Sulfonic acid (LAS) with Sodium hydroxide is that LAS is a weak organic acid and Sodium hydroxide is a strong inorganic base. The result is not a complete neutralization but an equilibrium, and in this system, pH tends to go down. The first sufferers are dyes (which shades depend on pH) and fragrances (if your fragrance is not designed for a more acidic system). What I did is to stop pH shift by adding Sodium carbonate, which serves as an alkalinity reservoir (being able to capture two H+ protons). Sodium citrate could work as well. So, to finally determine this is the same situation, I’d advise you to check if the pH at the beginning and when the system appeared, varied noticeably.