Monday, March 28, 2011
There have been some questions about the freshness of eggs, particularly on facebook, since we have laying hens who are quite productive. We have eggs of varying ages in the house, and I really try to keep them in order in the refrigerator. I only sell the freshest eggs, and use the older ones in my home (along with some fresh ones, but I try to use the older ones first).
There was some confusion the other day when a friend of ours stopped by to pick up her eggs, which I had packed for her in a cooler. The cooler didn't make it outside, and Number One, not knowing there were eggs in the cooler, gave her two dozen eggs from the fridge. Two dozen of the older eggs. Oops~
When I have older eggs or eggs that may be questionable, the first thing I do is put them in water. The ones that float are older, but may or not be bad. As eggs age, the air pocket inside them gets bigger, so the older an egg is, the higher it will float. You really can't tell if an egg is bad until you crack it, the yolk and/or white won't look right, or it will smell bad. In short, it will be quite obvious.
I don't wash the fresh eggs right away, because there is a coating on them from the hen that helps them keep longer. I found information about putting food-grade mineral oil on the eggs to "seal" them and help them last longer--up to six or eight months! While I don't plan to do this with the eggs we sell because they are only days old, I am doing it right away with the older eggs that we've accumulated and are going through here at the house. You really don't use very much oil at all.
Here is the information, from eggcartons.com:
"The surface of an egg shell is covered with thousands of microscopic holes which makes it quite porous. A natural coating referred to as the 'bloom' helps seal the holes, preventing bacteria from entering. As the egg ages, the bloom is worn away, which allows moisture to slowly escape and air to enter, forming the 'air cell'. Bacteria may also enter, and contamination may result.
"When eggs are washed to remove germs that may be on the surface the bloom is also removed, so a thin coating of oil is applied to take the place of the bloom. This works in the same way as the bloom, keeping the contents fresh for longer periods. The bloom also provides eggs with a natural luster or shine. Mineral oil not only protects your eggs as a sealant but it also restores the luster, the shine of the egg."
I also found this information on buying eggs commercially (from the grocery) in my The Best Make-Ahead Recipe cookbook, and I thought it was interesting, especially given the conversations we've been having. So here it is, word for word:
"Freshness: Egg cartons are marked with both a sell-by date and a pack date. The sell-by date is the legal limit for when the eggs may be sold and is within 30 days of the pack date. The pack date is the day the eggs were graded and packed, which is generally within a week of being laid but, legally, may be as much as 30 days. In short, a carton of eggs may be up to two months old by the end of the sell-by date. Even so, according to the U.S. Department of Agriculture, they are still fit for consumption for an additional three to five weeks past the sell-by date. Sell-by and pack dates are thus by no means an exact measure of an egg's fitness; they provide vague guidance at best.
"How old is too old? We tasted two- and three-month-old eggs that were perfectly palatable. At four months the white was very loose and the yolk "tasted faintly of the refrigerator," though it was still edible. Our advice? Use your discretion. If the egg smells odd or displays discoloration, pitch it. Older eggs also lack the structure-lending properties of fresh eggs, so beware when baking. Both the white and yolk become looser. We whipped four-month-old eggs and found that they deflated rapidly."
The Cook's Illustrated folks also said the Pack Date is the three-digit code stamped above or below the sell-by date. The number run consecutively, starting at 001 for January 1 and ending with 365 for December 31. So if eggs had a pack date of 078, they would have been packed on March 19. With a little math, you can figure out approximately how long your supermarket eggs have been sitting around (don't forget to add a week to 30 days for the time between being laid and packed!)
Rest assured, farm fresh eggs are nowhere near as old as supermarket eggs. And they taste much better too!
Let me know if you'd like to buy some, our chickens are laying like there's no tomorrow!