Old Cook's Tale: You Can't Whip Egg Whites With a Speck of Yolk in Them
You can't whip egg whites if there is even a tiny speck of yolk in them. It is known.
According to the common wisdom, that tiny drop of yolk in the photo is enough to stop a bowl of egg whites in their tracks and reduce them to a weepy, watery mess.
Ask any baker and they will tell you this is true. They may go on to recite the rest of the basics, described here by King Arthur Flour:
- The bowl and beaters must be clean and grease-free.
- Use a stainless steel, ceramic, or glass bowl, not plastic.
- Egg whites will whip higher if they’re at room temperature before beating.
Admonitions to ensure everything is dry, lest a drop of water render the whites too runny to whip, are often included.
Truth be told, this isn't a particularly onerous list. If you wash your dishes, they won't be greasy; separating eggs is not rocket surgery; most of us have glass or stainless bowls; and a few minutes in warm tap water fixes cold eggs.
Still, it bothered me. Such exacting instructions coupled with dire warnings if not complied with exactly.
If even the tiniest amount of yolk or fat gets into the eggs they will refuse to whip. To ensure that there is no grease on the bowl or beater, wipe them with white vinegar and rinse in very hot water. Dry well.
"Refuse to whip"...as if the egg whites go on strike at the sight of a fleck of yolk.
After hearing this for decades, I found myself whipping a few whites without noticing the tiny speck of yolk...at first. As the whites got foamy, a yellow streak caught my eye, portending disaster. Funny thing was, they whipped up just fine. I had done everything else correctly: room temperature eggs and a pristine glass bowl, so I put it down to a fluke.
Next time a bit of yolk got in the whites, I shrugged, whipped them and it worked. Since then, I usually let tiny bits of yolk that escape into whites stay there. It hasn't made a difference, at least, not one that I can discern.
While discussing this with some other bakers recently, someone asked how much yolk and I guessed it had been a drop or two of yolk in 3-4 whites. Not very much, the amount that I would drop in accidentally.
Not very specific, I know. This called for a test...
First Pass: One egg white and about 1/8 tsp of yolk, the amount that is in the plate above. Just because I was feeling difficult, the egg white was ~35F and I used a plastic bowl and immersion blender whisk, both of which I rinsed under cold tap water and shook off but did not dry.
I am such a rebel.
Needless to say, I expected this to fail miserably. The plan was that with each successive pass I would add an egg white until the yolk was sufficiently dilute and the egg whites could be whipped to stiff peaks. My expectation was that it would not work until there were 3 or 4 egg whites with that bit of yolk.
It did not fail.
In fact, other than taking an additional minute or so to grow into a boufy cloud, it was like any other time I have beaten egg whites.
So much for that Old Cook's Tale.
The foam was stable enough to hold the peak for eight hours on the counter of a 75 degree kitchen. (I poured off the liquid whites that accumulated in the bottom of the glass.)
This is certainly adequate for most uses of egg whites, particularly if it will be set by the heat of baking.
As an aside, while I was picking up quotes for this, I encountered some of the most exacting instructions for whipping egg whites I have ever seen at 101 Cookbooks. It included this bit, which I have seen before but it has always puzzled me:
To gauge when it [egg whites] has reached the correct consistency, take the whisk out of the bowl and turn it over. The foam should stay attached in a solid block, forming a tassel, like that on a clown's wig.
Colorful description aside, let's consider this for a moment. If the egg whtes are done, they stay in the bowl and you have a cool parlor trick. If they are partially beaten, however, they will fall out of the bowl, probably onto the floor. We geeks call this destructive testing and it's usually undesirable. Baffling...
added: Some folks have pointed out that the description above, which I snagged for its style, seems to be talking about holding the whisk upside down. On reread, perhaps. But I offer you the google results for "bowl of egg whites upside down over head"
The Old Cook's Tales series is a lot of fun to develop and there are more in the works. What have you heard and wondered if it was really true? Let me know and I'll try to check it out for you.