Hello.
10 g of milk powder was dissolved in 100 ml HCl, 23 %.
After 1 or 2 days at ambient temperature, a dark violet colour has appeared.
The composition of the powder is :
8,72 g proteins
0,16 g lipids (0,12 g saturated)
0,12 g carbohydrates
0,028 g Na, K, Cl, Ca, P, Mg
+ soybean lecithin as emulsifier.
Does anyone know which molecule causes this violet colour ?
Thank you.