"LG" > wrote in message
news
> Your Ribena probably had potassium sorbate in it, which inhibited yeast
> reproduction.. Then since there is little yeast to ferment and fight off
> the nasties, something else must have gotten in there and took over. Not
> surprising, really.

I know it had Sodium Metabisulphite in it, not sure about the Potassium
Sorbate. Either way the recipe said to boil it to "drive off" the
preservative. I'll probably try it again at some point and boil it for
longer.