I didn’t buy the red cabbage, it appeared in my fridge, the first time I have ever owned one.
“The red cabbage (Brassica oleracea) contains pigments known as anthocyanins. Anthocyanins belong to a large group of water-soluble natural pigments responsible for the attractive colors ranging from strawberry red to the blue color of most fruits, flowers, leaves, and some vegetables. Anthocyanins are commercially used as a colorant in acid solutions such as soft drinks. At various H+ concentrations these compounds rearrange their molecular structures giving rise to different colours.”
I decided to experiment. Boiling the cabbage gave the liquid the colour above right.
Into the pot I placed a hank of alpaca, with some silk roving and merino roving. An immediate colour change to ruby red. Mmm, maybe because of the alum mordant.
These are the colours achieved after a number of rinses – left pic from top: merino wool, silk and alpaca. I love the soft natural colours.
A big question mark at the moment is whether the colours will survive a wash or two or more. I’m not too hopeful after the reading I have done. But, nonetheless, it is all a fascinating learning experience.