"Lee Nowell" wrote in message
...
I am amazed at the results. Much better than I thought. They were all
rinsed with water and then put in the dishwasher to ensure all the caustic
soda was gone. Probably a bit OTT but hey. The oven trays have come out
clean but seem to have a coating of white powder on them. I initially
thought it might be caustic soda but now thinking it is unlikely given the
level of rinsing etc. Any ideas?

Its a form of soap, thats how some soaps are made, caustic and fat.

Is it safe to just wash it off by hand?

Yep, or do them in the dishwasher too if they will fit.

Was thinking of using vinegar to neutralise it if it was caustic soda.

It isnt caustic soda, its soap.

Maybe I am worrying too much.

Yep.

After all the warnings about caustic soda wanted to be careful

Thats a different problem splashes getting in your eyes when
dissolving it in water. Thats exothermic and a bit dangerous.