Why has the water turned Red when cooking Barley

[intermilan]

I was cooking Barley at the weekend no problem.
Im now cooking it in London same Barley same method also an AGA.
Ive thrown away two lots as Im vry worried by the fact that the cooking water turned red.
Does anybody know why.
Im assuming that it is dangerous.
Ordinary Barley from a well known supermarket. Bought it last week.
Many thanks

How strange. I've never heard of this. But then I don't eat barley 🤢