Not every product you purchase gives you a best when used by date, so when can you expect to toss out that bottle of unopened ketchup or that dish detergent? Real Simple has compiled a list of 77 everyday products with their recommended trash times. A chocolate bar, for example, will last up to one year after purchase. Maple syrup is also good for only one year. White rice has a shelf life of two years. Most alkaline batteries can be used up to seven years after purchase, and shampoo usually can last for two to three years. Guess what? Nail polish remover lasts indefinitely. Beer drinkers aren't as lucky. Your unopened cans and bottles last for only four months until they go bad. Have you cleaned out your cupboard yet?