Had a bit of a result today. Left a card with the owner of an Italian restaurant when out to dinner, about a month ago.
He called yesterday and I collected this afternoon. 220 ltrs of dark but all liquid KTC oil, with hopefully and ongoing collection of around 100 ltrs a month ... fingers crossed.
Anyway while chatting to my new best friend, Enzo the owner, I mentioned the colour of the oil and said that was strange because he obviously changed the oil quite regularly and I would expect that colour from oil that had been used to death. He recons that, as they fry a lot of floured calamari (and very nice it is too, it's the little, whole baby squid I've only previously found in Italy), it's the flour that turns it a dark colour.
Coupling this comment with my thoughts that what I was seeing previously was fine BCBs set me wondering. I'll do a titration on his oil to see if it's over used, but could flour remain throughout the process and manifest its self at the wash stage?