Question: I marinated some chicken yesterday and still have a fair bit of marinade left over. I’d hate to throw it out — can I reuse it?
Answer: It’s okay to reuse the marinade as a sauce, says the U.S. Department of Agriculture — but only if you bring it to a full rolling boil first and only if the marinade has been kept constantly refrigerated.
Marinade that’s been used on raw meat, poultry, and seafood contains raw juices that may contain bacteria and make you ill, so it should only be used once for marinading purposes. And since bacteria thrive in warm temperatures, you should always throw out marinade that’s been sitting at room temperature for two hours or longer (or one hour if the temperature is 90° F or higher), says the USDA.
Keep in mind that when you boil the leftover marinade, you’ll be altering its properties. You may find it's perfectly acceptable as a sauce. But if you’re hoping to use it again for marinating purposes, you'll likely discover that it doesn’t perform the same as it did originally.