Last night I saw a "Good Eats" where Alton Brown talks all about deep frying. He explained the difference between using saturated, mono-unsaturated and poly-unsaturated oils. The latter are the healthiest for us, but absorb unpleasant other things and go rancid more easily. Lard and beef tallow, saturated shortenings, don’t have the chemical "gap" that permit the poly-unsaturateds to absorb the bad stuff. He explained that if you ever take an oil to the smoking point that it is no longer useable, and that every time you heat the oil, that smoke point is lowered. If I fry nothing but french fries, I will use the oil on average 6 times, but my use is complicated by the fact that my Delonghi doesn’t rotate if the basin isn’t clean. BT is correct about the benefit of frying potatoes. I recommend the Alexia brand of Yukon Gold fries, as well as Tater Tots.