I've had a lot of questions in the shop lately about storing eggs and how to keep them at peak freshness. My only answer so far has just been to explain how we prepare and store our eggs, but I decided it was time to get a little more scientific and research-y and see what I could find out for a better answer. You know us - always up for a good experiment! Maybe all those years teaching the scientific method and science fair projects was going to finally pay off!
First, let me start with our current egg situation. We have always chosen to wash the eggs just with water, mostly because sometimes they can just be gross. Regardless of the number of conversations we've had with the ladies, they don't always choose to lay their eggs in the nice, tidy nest boxes we have for them. It is also a way to make sure that your eggs are clean and ready to use, since most of us aren't in a regular habit of washing our eggs before we use them. We haven't chosen to refrigerate them since they've sold quickly, but when asked, I always recommend that you refrigerate them when you get them home.
Next, let's explore Kansas and USDA rules. In Kansas, you can sell eggs without any regulation if you have 50 chickens or less in your flock. No one cares. For flocks sized 51-249, there are a few more rules. They should be cleaned, packaged and stored at 45 degrees. If you have more than 250 hens or sell wholesale, there is an egg license you're supposed to have a your eggs must be graded. We fall in that middle group, plus we have a retail store, so we technically need to start refrigerating our eggs. We're working on that plan. These rules make sense if you look at large-scale movement of eggs. Temperature control and clean eggs are needed to make sure eggs arrive safely at your retail locations.
Back to our scientific experiment. We had two questions.
Does washing make a difference in how long eggs last?
How does refrigeration effect egg quality?
To get our answers, we had basically four groups of eggs plus our control. We had unwashed and washed eggs kept at room temperature and in the fridge. We weighed the eggs on day 1 and took photos of each egg when it was cracked, including a set of eggs mid-week to monitor changes along the way.
Here's our data table with weights:
Egg Type | 5/24/24 Weight | 5/28/24 Weight | 5/31/24 Weight |
Fresh | 52 g | ||
Unwashed, Room Temp | 55 g | 55 g | |
53 g | 52 g | ||
Unwashed, Fridge | 55 g | 55 g | |
57 g | 57 g | ||
Washed, Room Temp | 57 g | 55 g | |
58 g | 57 g | ||
Washed, Fridge | 56 g | 55 g | |
53 g | 53 g |
My thought in weighing the eggs initially as an indicator of change was to see if the air sac inside the egg grew at different rates. The data really doesn't show much change, so I can't say that I learned much from the weights. Except that there was a change in 3 of the 4 eggs kept at room temperature. It's a small sample size, so take this information as you choose.
The pictures were much more telling. Let's start with the fresh, unwashed egg which I used as our control. [Side note for any science folks - all eggs were collected the same day from the same age and breed of hens. Similar size eggs were chosen for consistency and none were double-yolked or defective in any way.]
5/24/24 Control Egg: Nicely formed and perky yolk, the white stays together and there is some "watery" liquid around the egg that spreads more quickly.
On 5/28/24, we weighed and cracked the first set of eggs.
Unwashed, room temp Washed, room temp
Unwashed, fridge Washed, fridge
Eggs on left, room temp: right, fridge
There wasn't a lot of difference between any of these eggs, except we noticed the ones in the fridge still have super-perky yolks and the whites of the ones from the fridge were a little cloudy. Also, there are two little structures inside each egg called chalazae that hold the yolk in place. These for some reason become more solidly white after being refrigerated. The whites still stayed together and there was still the watery liquid, but it seemed to have more in the room temp eggs compared with the ones from the fridge. Merely anecdotal data, but just something we noticed.
We weighed the final set on 5/31. Here's the photos of those eggs.
Unwashed, room temp Washed, room temp
Unwashed, fridge Washed, fridge
Room Temp on left, Fridge eggs on right
After a week, we noticed more differences, but really only between the eggs kept at room temperature and those kept in the fridge. In the individual egg photos above, you can see more of the watery liquid in the room temp eggs than in the fridge eggs. The bottom comparison photo shows that the yolks of the room temperature eggs are flattening out compared with the fridge eggs. The whites are still clearly defined on the fridge eggs, as well.
One more comparison point photo:
Room temp, washed egg, 4+ weeks old
If you've been in the shop recently, you may have seen a box of eggs sitting on the shelf. If you've tried to take those, I always suggest you do not. :) This was basically a display box of eggs and I knew they were not at their prime. I wanted to see what one of them would look like as a comparison point with our other test. The yolk is flat, but good news - no more watery liquid! Because the whole white is runny liquid. I will add that it tasted fine this morning in our scrambled eggs, so it wasn't bad - just not something I would ever sell.
In order to complete a full and fair investigation, I currently have an unwashed egg sitting in my kitchen cabinet where I will let it stay for a month before cracking it open to see what it looks like at that point. I will update the post with that when it's ready.
Based on what we saw in our home test, washed vs unwashed really made no difference. I will be curious to see over the long term if we notice any more differences. The biggest difference in keeping your eggs fresh is actually keeping them in the refrigerator. There is no "farm badge of honor" gained from keeping eggs on your counter top. While they look cute and "farmy", I'm sure you can also buy some wooden ones on Amazon to achieve the same farmhouse vibe you're going for. So when someone tells you that you can keep your fresh eggs on your counter for 6 months and they'll still be fresh, I'm probably going to disagree. If you like room temperature eggs, buy only what you can use in a week and ask your producer when they were collected to make sure they'll be they're best for the full time. Or just put that box of eggs in the fridge when you get it home.
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