I've noticed over the past several months that restaurants (in my area anyway SF - East Bay area) seem to be using a different cheese on pizza. It seems okay when the pizza is hot, but it is absolutely disgusting when the pizza is cold or re-heated. It's opaque looking and is very slimy. I finally found a place that had 'real' cheese on the pizza and last night discovered that they too had gone over to the mystery substance. Does anyone have any idea what it is? Thank you.