Swill-cooked oil is oil that has been used several times, usually by restaurants, for frying.

地沟油是通常在餐馆为煎炸而多次使用的油。

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"Some was recycled edible grease, such as oil refined from swill and cooked oil," it said. "some was grease rendered from sewage, and some was recycled industrial grease."

“一些是可回收的食用油，例如将烧菜用完冲洗后的油提炼，”该报写道，“另一些是从下水道里捞来的油脂，还有一些就是可回收的工业用油”。

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