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Food Safety Feature Articles


Serve perfect and safe boiled eggs

Tammy Roberts, MS, RD, LD, Nutrition and Health Education Specialist, Barton County, University of Missouri Extension; With contributions from Christeena Haynes, MS, RD, LD, Nutrition and Health Education Specialist, Dallas County, University of Missouri Extension


This is the time of the year when millions of eggs are sold, boiled, dyed, hunted and eaten. To assure you have the best quality from store to table, it is important to know how to purchase, prepare and store your eggs.


When you purchase eggs, always make sure you are taking them from a refrigerated case. Check inside the carton for clean, un-cracked shells. Next, check the date on the package. Egg cartons that have the USDA grade shield have to display a “pack date.” This is the date they were washed, graded and placed in the carton. The pack date is a three number code representing the number of the day of the year the eggs were put in the carton. The number 001 would mean the eggs were packed on January 1; the number 365 would mean they were packed on December 31. When a USDA inspected egg carton lists a “sell by” date, the date may not exceed 45 days from the day the eggs were packed.


To prepare tender boiled eggs with no green ring, place eggs in a single layer in a saucepan. Add enough water to cover the eggs by one inch. Cover and quickly bring just to boiling. Remove from heat leaving the pan covered. Let sit for 15 minutes for large eggs, 13 minutes for medium eggs and 10 minutes for small eggs. Immediately run cold water over the eggs until they are completely cooled.


The green ring that sometimes occurs is a result of the sulfur and iron compounds reacting at the surface of the yolk. It can occur when eggs are overcooked or when there is a high amount of iron in the cooking water. The green ring may not look appetizing but the eggs are completely safe to eat and the taste is not affected.


After leaving the grocery store, take the eggs straight home and refrigerate them immediately. Store eggs in their original carton in the main part of the refrigerator, instead of the door. Make sure the temperature in the refrigerator is at least 40 F. The American Egg Board says that fresh shell eggs can be stored in their cartons in the refrigerator for 4 to 5 weeks beyond the pack date without significant quality loss.


Hard-cooked eggs spoil faster than fresh eggs. Eggs are actually porous and bacteria can penetrate the shell. When the hen lays the egg, she places a protective coating on them. When they are washed at the plant, a protective coating is added. That protective coating is washed away when the eggs are boiled. This makes it easier for bacteria to penetrate the pores of the shell. For this reason, it is important to refrigerate hard-cooked eggs within two hours of cooking them and use within one week. Consume egg dishes, like deviled eggs, within three to four days.


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Last update: Tuesday, April 19, 2011