Got a take away last night from one of the few T/As I still rate round here. It was early evening so they weren't busy and I watched them like a hawk, it being one of those open plan places. First thing the chef did was go out back and carry in a big 20 litre tin of KFC long life veg oil. He decanted some oil into a small (2Lt?) plastic tub on the counter along with all the other tubs of pastes and spices. This was the oil that ours and the other couple of phone orders he was making, were made with so no old oil in the curry. The flames on the burners where quite high but also "lazy" looking, when he cooked each meal there were the usual sparkly flames shooting up round the edge of the pan as he added the base but no real pyrotechnics just a few gentle sparkles. Further proof that the flames although high were in fact not particularly hot came when chef # 2 started doing some chapattis. These started off on the tawa but when almost done on the first side he transferred them to a large round wire scoop thing and finished them off over the high open flame on the burner, tossing each one as they puffed up like a football, if the flame had been fiercely hot the chapattis would have burnt given the time each took. We gave him a round of applause so he started showboating and did a couple spare which we were given along with some gratis chutney to munch while our meal was done, great stuff.
So, no evidence here of any old oil but they did have 2 huge stockpots of base on the go which he kept transferring ladles full from old to new which would make sense keeping some sort of consistency between batches.
The curry was excellent, one of their specials with fancy onions and capsicums, goodness knows how they do them but they are bloody lovely!
Cheers
CoR