How to Identify Quality Olive Oil Guest: Johnny Madge, professional olive oil taster, olive oil competition judge, and ambassador of Italian olive oil Professional olive oil tasting is no job to sniff at—with countless varieties, it is one of the most dynamic cooking ingredients in the world. But olive oils are not created equal. Johnny Madge will tell us how to identify the best. Vinegar Guest: Lawrence Diggs, “The Vinegar Man,” international vinegar consultant Vinegar—it’s in so many of the common foods and condiments we eat, it’s been around for thousands of years, and it can be made at home from leftover juice. This fascinating liquid is a bigger part of your life than you'd imagined.