Safe food handling begins at the supermarket. Buy cold foods last, before you check out. Place meats in a plastic bag to prevent contact with other groceries, and head straight home for the refrigerator. Avoid produce that's bruised or damaged, and thoroughly wash all produce - including organics. When purchasing fresh cut produce, pick only items that are refrigerated or surrounded by ice. Juices and milk that have not been pasteurized should be refrigerated at all times, and can be dangerous for children, the elderly, and those with weakened immune systems. Perishables and leftovers should not be kept above 40 degrees for more than one hour. The meats you do not intend to cook in one or two days should be frozen. Thaw frozen meats in the refrigerator, not on the counter. Contrary to popular practices, it's not necessary to rinse raw poultry before cooking. Only cooking can kill bacteria, and rinsing can spread bacteria to nearby surfaces. When using a cooler, keep perishables separate from beverages to reduce the warming effects of the frequent lid-opening, and keep the cooler out of the sun. Pack moist towelettes for washing up if there is no source of clean, running water at your picnic site.
Don't ruin your summer vacation - play it safe!