Indigo carmine (Water/Lake)
Indigo carmine is an organic sodium salt resulting from the formal condensation of indigo carmine (acid form) with two equivalents of sodium hydroxide. It is an indicator at pH 11.5 – 14, changing from blue to yellow. It has a role as a food colouring, a histological dye and a two-colour indicator. It is also known as Indigotine.
Food Color available at Humayun Wellchem Trading Concerns (HWTC) supplying all over Pakistan.