If a white radish is not fresh, you can say that it is "stale" or "old." You could also say that it is "not fresh" or "not new." It is important to use fresh ingredients when cooking, as they can affect the taste and quapty of the finished dish. If a white radish is not fresh, it may not have the same crisp texture or strong flavor as a fresh one. It is generally best to use fresh ingredients whenever possible in order to get the best results in your cooking.