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Are green eggs and ham safe to eat?

Coloring eggs, hiding Easter baskets and baking ham are common Easter traditions. Sometimes the egg yolk is green or the ham has a greenish tinge to it. What causes green eggs and ham? Are they safe to eat? Here are answers to these commonly asked questions.

Q: Why is the yolk of a hard cooked egg sometimes green? Is it safe to eat?

A: The green ring around the yolk of a hard cooked egg happens because hydrogen in the egg white combines with sulfur in the yolk. The cause is most often related to boiling the eggs too hard for too long. The green ring can also be caused by a high amount of iron in the cooking water. The green ring is harmless and safe to eat.

To avoid green eggs, hard-cook instead of hard-boiling eggs:

  1. Place eggs in a single layer in saucepan. Add cold tap water and cover by at least 1 inch above the eggs.
  2. Cover pan and bring to boil; turn off the burner.
  3. Let stand for 15 minutes for large eggs (12 minutes for medium eggs and 18 minutes for extra large eggs).
  4. Drain. Immediately run cold water over the eggs. This helps the green from forming around the yolks.
  5. Store hard cooked eggs in the refrigerator and use within 1 week.

Q: I've noticed a green tinge on the ham I bought? Is this normal/safe?

A: A greenish or yellowish cast on cured meats is normal. It is caused by the way light is reflected from the fat on the surface of the meat. Wrapping the meat in airtight packages and storing it away from light will help prevent it. The greenish or yellowish tinge is not a sign of spoilage or poor quality. It is safe to eat.

Q: How long do I have to cook my ham? How do I know it is done?

A: Cooking times vary depending on the cut and size of the ham. The only way to know if the ham has reached a safe temperature of 160 F is to insert a food thermometer in the thickest part of the ham. Stay away from the bone.

Cooking times for various cuts and sizes of ham cooked uncovered at 325 F

Cut of ham Weight (pounds) Time per pound
Uncooked fresh bone in ham 12-16 22-26 minutes per pound
Uncooked fresh boneless ham 10-14 24-28 minutes per pound
Uncooked fresh half bone in ham 5-8 35-40 minutes per pound
Whole smoked fully cooked bone in ham* 10-14 15-18 minutes per pound
Spiral cut, whole or half smoked fully cooked bone ham 7-9 10-18 minutes per pound
Half smoked bone in ham (cook-before-eating) 5-7 22-25 minutes per pound

 *Fully cooked hams can be eaten cold or reheated to 165 F.

Q: When I go to the in-laws to celebrate Easter, they leave the ham out all afternoon for folks to graze on, is this safe?

A: No. Leftovers should be refrigerated with 2 hours of cooking.

While it may be convenient to leave leftovers out instead of putting them away, it could make someone sick. The foodborne illness, Staphylococcus aureus has been found in high-protein foods, even salty ones like ham. These bacteria are found on our hands, in our noses and in infected cuts and can be transferred to food very easily. Symptoms of this foodborne illness show up within 1 to 6 hours after eating the contaminated food. To avoid getting sick, it's important to wash hands well and refrigerate leftovers with 2 hours of preparing them.

Suzanne Driessen, Extension educator

Reviewed in 2021

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