Oil can be surprisingly fussy. You generally fry at temperatures that are quite close to the oil's smoke point, and the more a quantity of oil has been exposed to heat, oxygen, and impurities, its smoke point decreases and the oil breaks down. Frying is usually done between about 350°F and 375°F (175°C and 190°C), while the smoke point of peanut oil starts out around 410°F (210°C).

If you keep oil clean, it can usually be used 5 to 7 times. How well you control the temperature of the oil (keeping it from overheating), how dry the turkeys are when the go into the fryer, and how committed you are to skimming off impurities will determine how many turkeys you can fry. The oil will darken as you continue to use it, but this is not a problem until it is accompanied by an unpleasant odor, excessive foaming, and eventually smoke and uncontrollable flames. We suggest you call it a day at the unpleasant-odor stage.

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