Chicken can be safely marinated for up to two days while refrigerated. However, most marinades are able to penetrate the flesh of a chicken to instill flavor after just two hours. Some types of marinade, particularly those with a high acid content, toughen meat when used for extended periods.
Food-grade plastic bags are an easy way to marinate chicken and allow for simple cleanup. However, chicken can also be marinated in any food-grade plastic, stainless steel or glass container. Chicken should always be covered while marinating in the refrigerator. Unless the marinade is boiled after use to marinate raw chicken, it should be discarded.