If you long to sample potato salad, devilled eggs or other mayonnaise-laden foods at summer picnics but are afraid of the gastrointestinal woes that might result, you can cast your trepidation to the wind. In 2000, a very comprehensive review was published in the Journal of Food Protection that looked for all the reports and studies of illness and death caused by bacteria in store-bought mayonnaise. And they found no reports! The need to avoid mayonnaise is completely unfounded! Mayo gets a bad rap because people used to make it at home using raw eggs, and those raw eggs can contain nasty bacteria called Salmonella. However, commercial mayonnaise is much safer; in fact, it’s pasteurized and sterile. At a picnic, you are much more likely to get ill from unwashed fruits or vegetables or undercooked meat. In general, you also should avoid foods that have been outside for more than two hours, or less if it’s really hot.