Why - please - can you make a sauce, cook it for several minutes to the exact consistency, put it to cool - bring it out & need to add almost as much liquid as before??
Think it is mainly to do with temperature & starch expansion.
Have you tried the comparison and quantity variation with other starches such as wheat flour, rice flour, corn four, or arrowroot?
The results would be very interesting.
The only other I've tried is Cornflour - very strange to handle.
Despite searching in McGee & Lundberg, I still can't figure why, having thickened - as normal - on cooling, sauce can then take so much more liquid to re-thin it. Just re-heating doesn't do it.
Must try making it much thinner to see what happens.
Tim it's something that frustrates me, as most of us will make sauce in advance supposedly making serving a little easier.
We need Baccy man for this one hope he's not too far away? I will be back later to see if he is able to throw any light on it :-\
Simple answer is cook out over a low heat for 30 minutes after the desired consistency is reached & stir regularly whilst cooling to limit the amount of gelation that occurs.
A more comprehensive answer will take a while to write in a way where I don't confuse myself let alone anyone else as there are lots of factors that influence the consistency & the processes of dextrinisation, gelatinisation, gelation & retrogradation to explain.
It will have to wait until later though as the sun is out & I have been informed the floodwater has receded so the bridge is back in use which means I can get to my plot for the first time in a week & a half.
Ah, so go on cooking beyond the desired consistency. Must try!
Me too, many thanks Baccy man.