"Kathy" > wrote in message
...
> I read recently that if one substitutes oil for shortening in baking, the
> result comes out greasy because shortening is whipped full of air and oil
> has no air. Still, it seems to me that if one knew the air-to-grease ratio
> in shortening, one could figure out an oil-for-grease substitution. I've
> been experimenting in cookies, muffins, biscuits, and pie crust and coming
> out somewhere between a third to a half cup of olive oil for every cup of
> shortening the recipe calls for. But that's just guessing. Does anyone
know
> what the exact amount should be?
>
> (Of course, even with the exact amount, an oil-based product will be
> different than a solid grease-based product. I'll accept different, so
long
> as it's still good and it means I can get away from using Crisco.)


Solid shortening has nitrogen whipped into it. That's what makes it opaque.
The nitrogen is 20% by volume as I recall. Oil has more shortening ability
than solid shortening. Therefore, I would start with a 25% reduction.