(AP) -- Phil DeVore pulls a folded piece of aluminum from a murky pond. The aluminum looks like a piece of siding that's blown off a building, but DeVore knows it's much more valuable than that. He slips a rubber band off the aluminum and unfolds it. He likes what he sees -- 50 or 60 glistening black leeches. They're your common ribbon leeches, Nephelopsis obscura to aquatic biologists.
After its initial use, cooking oil can be refrigerated or frozen and reused for another six hours of cooking (see References 2). Don't reuse cooking oil if it smells rancid or you can't heat it without smoke developing, as this indicates significant deterioration (see References 1 and 4).
Quick Answer. Canola oil, blended oil, olive oil and safflower oil can all be used for up to two years past their expiration date when unopened. Sesame oil, vegetable oil, corn oil, coconut oil and hazelnut oil all can be stored up to one year past their expiration date when unopened. Keep Learning.