Food safety in egg consumption can be easy, Purdue professor says

Eggs are an excellent source of protein consumed all around the world. But no matter where eggs come from, proper egg storage and sanitization are key factors in healthy consumption of eggs, according to Yaohua “Betty” Feng, an assistant professor of food science.

Whether eggs are purchased from the dairy aisle of your local grocery store or directly from a roadside farm stand, Feng said the possibility of Salmonella contamination is a risk you need to consider and can easily protect against using the proper methods.

Eggs come out of a hen in the perfect packaging, with a bloom, or protective mucus, coating the shell. The shell encapsulates a protective membrane around the albumen, commonly known as the white, and the yolk.

However, research shows that salmonella can be found in whole, uncracked eggs, due to bacteria within the hen's reproductive tract before the shell forms around the yolk and white.

After an egg has been cooked thoroughly to 165 degrees, Feng said it needs to be immediately consumed or immediately placed in the refrigerator, with a temperature sustaining 40 degrees Fahrenheit. A properly stored cooked egg is safe to eat for one week.

What about eggs collected from back yard chickens? When the egg is dropped from the hen, the bloom still coats the egg, protecting it from potential contamination from salmonella. But Feng says it is still necessary to wash and sanitize the eggs.

“Properly washing these eggs is an important step in safe consumption, then they need to be refrigerated at 40 degrees Fahrenheit, where they will be safe for three to five weeks,” she said. “But regardless of where the egg comes from, you should always cook the egg thoroughly to lower the risk of food-born illness.”

No matter how expensive an egg or what its store label reads, Feng said those are not indicators of food safety.

“Salmonella is natural, so no egg is superior to another,” she said. “Maintaining washed hands to avoid cross contamination and thoroughly cooking our food are two of the biggest ways we can avoid food born illness.”

Featured Stories

Hunter Foland works with chicks at Purdue ASREC
Why Spring Start was the right beginning

Raised in Greentown, Indiana, a town just east of Kokomo, Hunter Foland grew up surrounded by...

Read More
Ty Hoskins takes measurements from a mesocosm; an FNR alumnus fights a wildfire; a doe stands in snow
FNR Shares Most Read Stories of 2025

2025 was a productive year for Purdue Forestry and Natural Resources across the three land grant...

Read More
Mountain Bluebird taking wing, a migratory species that ranges widely across the western North America.
Research uses radar to expose sky’s organized, living habitat

When people think about habitats on Earth, they likely picture forests, oceans or grasslands. Few...

Read More
Natalie Nenneker poses with apples
Rooted in sustainability: Growing a future in food and farming

For Natalie Nenneker from Wadesville, Indiana, Purdue Agriculture offered the perfect place to...

Read More
person running
Purdue Agriculture athletes honored for academic performance

Two Purdue Agriculture student athletes were named Academic All-Big Ten Honorees for the fall...

Read More
Purdue University's bell tower at the West Lafayette campus with greenery in the foreground.
Purdue welcomes two faculty members for Spring 2026 semester

Camila Nicolli, research assistant professor of mycotoxin fungal biology in the Department of...

Read More