Tips for Keeping Snacks SafeAlways wash hands before preparing or eating a snack. This is the one of best ways to prevent food spoilage and contamination. Wash all fruits and veggies under cold running water. Clean all lunch boxes, thermal bags, plastic utensils and containers in hot soapy water. DO NOT re-use plastic wrapping and bags. Keep foods cold -Yogurt, deli meats and cheese should be kept cold. -Be sure to keep lunches in the fridge until the morning and include an ice pack or frozen juice pack when sending lunches to school. -Left-overs that are to be re-heated in the microwave should also be kept cold until ready to eat. Keep hot foods hot -Use a thermos or insulated bottle to keep foods hot.