“I think we need to toss the oil that is stored in the cupboard,” I said to my intern.She agreed to do the “sniff test” on the variety of oils. She reported several of the bottles had a crayon-like aroma, a hallmark of rancidity or spoilage.She also checked the best-if-used-by dates. Some of the oils were within their storage life, but their odor, a sign of rancidity, was?...