Understanding the Rainbow Sheen on Ham

Is your ham safe to eat?

Preparing a Baked Ham

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If you're just learning how to cook, it's important to be able to tell if certain foods have spoiled. It isn't always easy. Sometimes rot is easy to spot but other times not so much. When it comes to meat, it can sometimes be hard to tell if it's gone bad or not and ham is a prime example of this. Most people assume any type of color change is a bad sign but this isn't always the case. Learn what it means when your ham takes on some new colors and if it's safe to eat. 

What Is the Rainbow Sheen on Ham?

You may have noticed a glistening, sometimes greenish, rainbow iridescent effect on cut ham. This is not necessarily an indication of spoilage. Hams using nitrates and/or nitrites as curing agents undergo pigment changes when exposed to light and air due to a chemical reaction. These same nitrates are the cause of the meat color remaining rosy red, even when fully cooked.

Are Nitrates Healthy or Harmful?

There's a great debate in the health food world over the safety of nitrates in food. While most scientists find that unless you have a specific allergy to nitrates, they're a safe food additive. Some nutritionists think that nitrates, especially in large quantities, can cause all sorts of medical issues from indigestion to cancer.

How to Tell When Ham Has Gone Bad

Signs that your ham has turned are similar to signs of spoilage in many other types of meat. A bad smell is a big indicator that you don't want to eat that meat. If your meat is turning an unhealthy green, gray, or black color that's a sure sign it's gone bad. While ham is usually cured in a way that makes mold unlikely, if your meat ever starts to grow mold, it's time to get rid of that science project. You also never want to sniff a moldy bit of meat. Those mold spores can enter your respiratory system and make you sick. When you discover mold you're going to want to get rid of the food item as soon as possible.

It's a good idea to wrap the meat in a plastic bag before you toss it to prevent the mold spores from becoming air born and making people sick. If your ham or any other meat has a slick, slimy feel or film coating it, that's another bad sign. While there are a lot of ways your meat can spoil, the good thing is when it does it's usually pretty easy to spot. Some foods, like cheese, can be salvaged if parts begin to turn, ham and meat products generally can not. Throw the meat away and fully clean the container that it was stored in.