Originally Posted by Alix
[FONT=Comic Sans MS]Angie, there would be a big difference. I don't know the science behind it all, but the cooked variety is pretty much just cornstarch, milk and some flavoring. The instant stuff has some other thickening agent (I'd have to go hunt that down) and lots of other chemically stuff. Not sure how it would work.
The instant mix probably has "pre-activated cornstarch" in it. Basically, it is cornstarch, but, it doesn't have to be boiled to start it thickening. I've used a commercial product called "thicken-up" to tighten liquids that never get boiled.