Making Mayo by hand , using whisk , emulsion breaks down

It's important to determine whether your emulsion actually broke immediately or was just creaming.

I'm going to trot out this diagram again from yesterday:

(source: Cube Cola)

Creaming occurs when the oil drops, which are less dense than the water, float to the top. As long as the droplets don't coalesce, you can still fix this with agitation (whisk, blend, or shake vigorously).

Emulsions with coarse particles (of oil) are much more prone to creaming, because their increased buoyancy makes them more able to push up past the water molecules. You want to have a very fine "mist" of oil suspended in the water; if you were using a squeeze bottle, perhaps the individual drops were simply too large. A ketchup bottle in particular would not be appropriate for this sort of thing, you'd want to use something closer to a syringe (or just get an actual syringe).

Now if you keep adding oil to a creamed emulsion or let it sit too long then it will also start to coalesce, and coalescence and creaming together are what cause an emulsion to break completely. This, you really can't recover from, except to let it separate completely, skim off the fat, and start over.

So, to recap:

• Your oil drops may have been too large;
• You may not have been agitating enough, especially when it started to cream;
• You may have added too much oil after creaming had already started.

I also agree with commenter Henrik that the amount of oil sounds a little high; 3/4 cup would be more reasonable for 1 egg yolk. But since you say you only got 1/3 of the way through, that's clearly not your problem here.

I think it is important to use a whisk (or one of those hand-held blenders!).

You cannot over-whisk, the big danger is getting tired/bored after a while and dumping too much oil in at one time.

I don't bother pouring the oil in a steady stream (it is too hard, as well as risking a 'collapse' such as you experienced), instead, using a small plastic measuring cup with a spout, I pour in approx. a teaspoon full, whisk the mixture until the oil is fully incorporated, then add more oil and so on.

I think it takes about 15 minutes to incorporate .75 cups of oil, however I can't be sure because after a few minutes I seem to enter a sort of oil-whisking trance state...

I think you add the oil too rapidly.

• Only add more oil, if you already have something that looks like mayonaise, don't add it too soon.
• More importantly, just a few drops of oil at a time. Don't get too confident.

Some details: the amount of mustard seems a little small (in comparison to the other amounts). Secondly, you can add a pinch of pepper if you want. Thirdly, you can add a tablespoon of water when you're done, if you think your mayonaise is too greasy.

And just a personal tip: I prefer making it with a fork instead of a whisk.

My mom makes mayo with only yokes and oil, adding salt only at the end. You don't want an oil with strong flavor. Trader Joes canola works great.

Room temperature ingredients are important. And so is the agitation. Alton Brown had an episode about it and he mentions a blender is too violent and you have to add one egg white in to help the egg "molecules" from getting shredded.

My mom hand whisks on a plate, sometimes using just a fork, starting with egg yokes, then adding the oil slowly. She has the technique down; pours the oil from a measuring cup, starting with drops and then once she has an emulsion, a steady (but thin) stream.

When the emulsion is created the consistency changes drastically from viscous liquid to something that seems more elastic. It is sudden and really almost magical. It should take a very short time to get the emulsion. After you get it, you don't need to even whisk anymore, just mixing and stirring (less intensity than whisking). The whisking part really takes some stamina; you are doing tiny Arsenio Hall arm pumps over the plate as fast as you can.

Any yoke/oil mixtures that fails you can the pour in slowly as you mix after you have the emulsion started.

At the end she adds salt which really stiffens it up. It is incredible to me that you can taste this straight up and it doesn't taste like oil (or only very slightly). She puts it on potatoes that have been boiled, peeled, and cut into inch size cubes. Then you absolutely cannot taste the oil.

I have tried about 10 times and only got the emulsion to happen once. If you can taste oil you have done something wrong.

EDIT

I've since been successful making it, again, with room-temperature ingredients, but using a single whisk on a hand mixer. It comes out way more like "grocery store" mayo this way (more white) than the hand version (which comes out very yellow).

Today I'm going to try with a power drill set to low speed, because I feel like the hand mixer is too fast, and in a jar or cup to cut down on the splatter mess, too.

EDIT

The power drill worked nicely, because I was able to whisk much more slowly - so I got the more drippy, yellow version, as opposed to the firmer whitish mayo.

The temperature of the eggs is very important. They must be at room temperature. But I have been told that the eggs should never be refrigerated at all, if you are making mayonnaise (by a lady who has chickens).