Yes, I screwed up a boiled egg.

June 9, 2011 3:02 PM

I didn't know it was possible to mess up boiled eggs. But I did. What happened?

Here's the scenario: Making soft boiled eggs. I do this often and never had this happen. I believe I followed my normal procedure. Eggs: fresh (our own chickens), room temp. Water: fast boil. Procedure: Drop into boiling water. Time for 4 minutes. Remove from pan and rinse under cold water. Put in egg cups.

Now - every other time my eggs come out fine. But this time, when I sliced the top of the egg off, the yolks practically squirted out as foam. Foamy egg yolks? Eww. So I tossed that egg to one side. Got the next one. Same thing. My husband found his were the same. In all, five eggs, all the same horrible foamy yolk.

I then took the same pan, the same water that just boiled, 5 more eggs, and repeated the procedure above. This time I know that I followed the procedure exactly because I wanted to make sure it wasn't something I was doing wrong. These next 5 came out perfectly.

Now some eggs from the foamy batch were from the day before's take, some were from that day. Ditto with the next batch. So I can rule out a problem with a certain day's eggs, or a certain chicken. The pan was the same, even the water was the same.

So what could I have done wrong the first time? I'm mystified.

posted by anemone to Food & Drink (24 answers total)

I've never put eggs into boiling water, rather I put eggs in water and bring pot to a boil. It sounds like your second set went into water that wasn't actually boiling when eggs were added? Perhaps that made a difference.
posted by shoesietart at 3:16 PM on June 9, 2011

I'm with shoesietart on this...I never put eggs into boiling water, but rather bring the pot to boil with the eggs already in. Also, hard boiled eggs - and especially soft-boiled eggs - should actually be poached-in-shell rather than full rolling boil. It takes longer, but the less harsh the bubbles, the better it is on the proteins. This way you don't end up with rubbery egg. The same holds true for poached chicken (full bubbly boil does weird stuff to protein fibers).

As for the foamyness, perhaps the temperature shock shook the yolk inside the shell and you ended up with a super scramble encased in the whiteness in there...it's kind of like when you whisk hollandaise in a saucepan too vigorously.
posted by iamkimiam at 3:30 PM on June 9, 2011

I don't really have an answer as to why that happened but I'm going to pipe in that, like you, I cook my eggs by bringing the water to a boil first and then add the eggs after it's at a fast boil. I do not think this method is the source of the issue.
posted by joan_holloway at 3:37 PM on June 9, 2011 [2 favorites]

I generally bring the water to a boil, then reduce the heat and add the eggs. I've often had weird things happen when I add eggs to water that is actively boiling. Never had foamy yolks, though. Yuck!

Is it possible that the issue was with the eggs, and not in the cooking method?
posted by I_love_the_rain at 4:42 PM on June 9, 2011

The reason for putting the eggs in the cold water is that they will be closer to boiling temperature when the water itself boils, therefore the cooking time is way, way, way more predictable than if you drop them into boiling water.
posted by plinth at 5:04 PM on June 9, 2011

The counterargument for putting them into already-simmering water is that it can be difficult to tell exactly when the water came to a boil, which makes accurate timing impossible. If you add the egg — room-temperature, not fridge-cold; submerge it in a bowl of comfortably warm water to bring it up to room temp quickly if need be — to simmering water, you know to the second when it started cooking and can time things accordingly. That's how I've always done it and it works fine. Never had foamy yolks, so I don't think that's what caused that.
posted by Lexica at 5:22 PM on June 9, 2011

But, guys, the key here isn't the procedure, it is that she always does it this way and then, for seemingly no reason, the yolks were foamy on these eggs.

When you repeated the performance, were the eggs warmer than the first batch? Did you perhaps take them all out of the fridge at the same time and the second batch had time to wrm up to room temp? Perhaps iamkimiam is on to something.
posted by Foam Pants at 6:09 PM on June 9, 2011 [1 favorite]

anemone, your description is unclear. For the yolk to form foam, as you put it, there would need to be air in the yolk while cooking. That's pretty much impossible: the air pocket in eggs is never adjacent to the yolk (14 in this diagram), so iamkiman's suggestion doesn't make sense, even if things did get shaken up or whisked – the point of whisking hollandaise is to introduce air into the sauce.

Did the yolk boil out (unlikely)?

Did the yolks only foam as they were squirting out; i.e. you cut such a small opening in the egg white that any liquid squirting out would form foam?
posted by halogen at 6:34 PM on June 9, 2011

The eggs you used were possible coated or washed improperly causing a build up of pressure within the egg. When you cut into them the pressure was suddenly released. Regular egg shells are porous, allowing the egg to "breathe". Use a pushpin to make a small hole in the fat side of the egg before boiling to prevent this.
posted by Infernarl at 6:35 PM on June 9, 2011

Response by poster: halogen: good question. I can't say for sure. There did seemed to be some kind of pressure in the eggs because there was a squirting/spitting that doesn't happen when they're done correctly.

Infernarl: it's possible, but then why did the next batch, which I handled in the exact same way, come out fine?

If it was even just a couple of the first batch with foamy yolks it wouldn't be driving me so crazy. I'd just chalk it up to the eggs themselves. But all five? I suppose it could be that there was something odd about each of those five, but the odds seem improbably high.

Maybe the question should be: If I want to boil some eggs with squirty foaming yolks, how would I best do that? (Not because I want to repeat the process, but because I want to make sure that I don't.)
posted by anemone at 7:16 PM on June 9, 2011

Infernarl, the eggs were laid by the OP's chickens on the same day and the one previous. You're describing commercial practices.

Harold McGee's got a long, detailed section on egg composition, chemistry, and cooking. p. 113 subheading: "Yolks Can't Foam Without Help". The help it requires is more water.

Egg whites have lots of water. But white doesn't normally foam in the shell either, because foaming requires that air be incorporated.

Is it possible someone has pulled a little prank? Injected a baking soda solution into the yolks or something?
posted by nakedcodemonkey at 7:28 PM on June 9, 2011

Hmm. If I were challenged to reproduce this effect, double-acting baking powder would be my first attempt. Add minimum amount of water that makes a syringe-administerable solution. Let the first batch of bubbles die down to minimize pressure. Inject. Use a wee bit of wax (or crazy glue .if I knew the prankee for sure will be be too grossed out to eat it) to seal the hole. The second set of bubbles are activated by heat, so pressure builds during the boil. Open, voila, presumably egg foams.

If the thing has managed to not explode on its own.

This is all speculation. Someone got a syringe hanging around?
posted by nakedcodemonkey at 7:35 PM on June 9, 2011

the only thing i found through a cursory internet search on foamy egg yolk is this on "backyardchickens forum." in this case, the foamy yolks indicated that the eggs were rotten or old. so that may answer "how do i best boil eggs with squirty foaming yolks"..

is it possible that of the eggs you had to choose for your first and second batch, the foamy batch you chose happened to be from an older take, and the good batch was from the day of? i know those are small odds-- but sometimes when i store eggs in my fridge (i don't know how you store your fresh eggs), don't eat them all, and buy more eggs, the older eggs get shifted back and i may forget about the ratio of old eggs to new eggs. i agree it can't be the boiling method, as i've done that before with no problem. you should have less temp shock anyways, as you start with room temp eggs.
posted by ilk at 7:46 PM on June 9, 2011

What about the chicken?! The chicken! Perhaps you have a layer of incredibly foaming eggs. Great for parties!
posted by amanda at 7:49 PM on June 9, 2011

I'd go with "off eggs" ... or (just throwing it out there) is it possible they were fertilised?
Gross, I know, but it's all I can think of.
posted by indienial at 8:15 PM on June 9, 2011

My method for boiled eggs is different than yours and probably takes slightly longer; however, it is ensures consistency in the heat loss from product being added to already boiling water, and what we're looking for is consistency:

1. Place eggs in a pot. 2. Cover eggs with at least a half inch of water. 3. Bring the water to a rolling boil for 15 seconds. 4. Turn off heat. 5. Cover. 6a. For soft boiled eggs let sit for 6 minutes. 6b. For hard boiled eggs let sit for 10 minutes. 7. Chill immediately

End result: Whites are white and yellows are consistently yellow with no discoloration at the separation.

I have not seen something fail to coagulate in the manner that you have described, and I can safely say I've cooked at least (roughly) 60(5 dozen)x52(weeks)x3.5(three and a half years cooking for high-end hotels)=10,920 soft-boiled eggs in this manner and had some fail, but never in a foamy mess. With what you are saying where these shot out, I'm thinking they may not have been as cooled as normal, and maybe there was a pressure differential as a result.

I just sampled six eggs, cooking them in my method with shorter cook times (two at 3 minutes, 2 at 4 minutes, one at five minutes) and improper cooling (one at each temp not cooled) - to shoot for a runnier egg, and I was unable to generate a foamy egg as you described, so I really don't think that that's something typical or repeatble.

I should note, the 3 minute eggs did not have good coagulation in the whites.
posted by Nanukthedog at 9:56 PM on June 9, 2011 [1 favorite]

Is it possible you just weren't careful putting them in the boiling water and they got cracked right away, letting water in? then, because it was boiling water, the egg white sealed up fairly quickly?

that would account for the water possibility.
posted by rich at 6:06 AM on June 10, 2011

I use this thing with good results.
posted by donovan at 7:35 AM on June 10, 2011

Did you dive into the first batch of eggs while they were still really hot, much hotter than they usually are when you first crack into them? And, when you say foamy, were they cooked at all? Was it a rolling boil the first time around? Was it a full rolling boil the second time around.

My thing is, since the eggs were pretty much identical, I think it has to do with a delicate balance of temperature, both during the cooking and during the eating. It's the only thing that could be different.
posted by Foam Pants at 9:18 AM on June 10, 2011

Have you tried cooking eggs any other way? Or just cracking one or two raw ones open? Maybe it really doesn't have anything to do with the cooking method at all, but rather an indicator that some thing is going on with the chickens.

Barely resisting temptation to make 'chicken came first' joke.
posted by iamkimiam at 10:29 AM on June 10, 2011

Response by poster: Foamy pants: that's my take too. That it had to be something I did. I can't say I remember exactly what the water was doing the first time, but the second time it was my usual full boil. But the whites both times were definitely cooked. Indienial: There is a possibility that they were fertilized as we have a rooster. But it's odd that we wouldn't have come across this scenario once until this day, when it happened 5 times. And I wouldn't have said they were "off", as they were definitely fresh, and although very unappealing, they didn't smell of anything. However, that certainly crossed my mind at the time.

Rich: It sounds like that would be the only possible way. As nakedcodemonkey linked to re: yolks foaming with water. But usually, when the shell breaks during cooking, you get some kind of white leakage into the water. There was just none of that. And yet....? How else would water have gotten in there? It's not like I soaked them in anything prior to cooking where there'd be a seepage into the shell.

I'm glad my husband was there to witness the preparation and result or I'd be seriously wondering if I imagined the whole thing. Oh well, it may remain a mystery. Very strange.
posted by anemone at 1:32 PM on June 10, 2011

I believe it's very unlikely an accidental shell crack would be enough to do it with one, let alone all. The chalazae and outer membrane are expressly designed to keep trauma to the egg from easily busting up the interior. Even if the shell and outer membrane had broken in all those eggs, there would be tell-tale white as you've noted, plus we're talking about a trauma big enough to cause failure of the yolk membranes too.

McGee notes (p. 81) "...osmotic imbalance creates a natural pressure for water in the white to migrate across the yolk membrane. At refrigerator temperatures, about 5 milligrams of water cross into the yolk each day. This influx causes the yolk to swell, which stretches and weakens the yolk membrane." But your eggs were insanely fresh. And I've boiled eggs 8+ weeks old without being troubled by gasses or broken yolk membranes. The outer one has merely thinned a bit (the point of boiling older eggs, after all).

Do you salt your water? Salt is nature's adjuster of osmotic pressure. On p. 116, McGee notes that the egg gets tenderized by a brine-quantity of salt and immersion directly to boiling water; and that "swollen yolks and split whites..result when the egg absorbs the pickling liquid too rapidly..."

New theory: unusually thin shells & membranes (maybe they got stressed for a day?) + unusually high salt + quick boiling
posted by nakedcodemonkey at 3:00 PM on June 10, 2011

Perhaps the protein curdled. The yolk is a sort of emulsion of protein, fat and water. Maybe, due to a perfect storm of water temperature and egg temperature, the protein in the yolk constricted soon after being immersed, forcing the yolk to separate into its components. Then, due to the heat of cooking, that water, no longer held in check by the protein, turned to steam. Hence, steam and curds instead of a creamy yolk.

It sounds all scientific and shit so it must be right!
posted by Foam Pants at 3:18 PM on June 10, 2011

The concept of fat (eggyolk) foaming is weird to me as I've always been cautioned to never, ever let even the tiniest fleck of yolk contaminate egg whites that you're going to beat into a meringue since the fat in the yolks PREVENT the foam from forming. But I'm going to Ask An Expert, meaning one of our peptide chemists, since he's standing here shooting the breeze...

ok quoting direct from Chemist Guy: eggyolk protein is a colloidal lipid, and under the right circumstances it will indeed foam. Like others have indicated, it cannot foam without air+water contact. We deal with foaming in processing in the plant, so they're good at knowing how to make stuff not foam.

Educated guess from chemist: something went wrong with that entire batch. He suggests either the eggs were off somehow (hydrogen sulfide can cause foaming - did they smell terrible? I assume you would have noticed that...) or someone pranked you, or overly high heat on initial contact cracked the eggshells and introduced air and water to the yolk. Injecting air into the yolk with a fine needle thru the shell could cause foaming. Cracks in the shell can cause foaming, and is the most suspect possibility. He asks if there's any chance you put them in at such a high boil that all 5 shells cracked?

Suggestion for future: don't put eggs directly in high heat / water at a boil. I never do this, and as others noted above it's a good way to mess up your eggs regardless of cook time. Everytime I've tried to do hardboiled eggs by dropping them into boiling water, the shells have cracked and they've had big gooey eggwhite boogers hanging off them / all over the pan.

Ah another question from Chemist Guy: did or do you salt the water you boil your eggs in ? Apparently salts retard foaming in lipids. Something to consider, anyhow.
posted by lonefrontranger at 5:14 PM on June 10, 2011 [2 favorites]