boring-adult posting on main sorry but if a recipie tells you that you can make a mayo with immersion blender and just throw everything in there at once, that recipie is LYING to you and should be banned <just learned this
“blah blah blah all you need is an immersion blender” LIES, you have to make mayo the traditional way, with a food processor and a measuring cup and pouring the oil into the emulsification at the absolute slowest rate you can physically manage and still be continuously adding oil, until you actively die of boredom while standing over a horrifically loud food processor! That is how it works! That is how the mayo gets made!
Also I was not making the mayo because I have any sort of goals or aspirations, I was making a mayo because of food allergies and not being able to use canola oil mayo in a slaw, part of my monthly attempt to feed my roommates while also not killing them.
Random culinary knowledge time!
So, mayo is an emulsion.
Emulsion just means “mix of two things that don’t want to mix”, in cooking that’s usually, not always, oil and water. (Sometimes it’s fat and another fat, sometimes it’s alcohol and oil, sometimes it’s air and fat and water (ex: ice cream), and so on).
And emulsions require either a lot more water than oil, or a lot more oil than water. (In general, a lot more of one than the other, but that’s not always the case outside of oil/water emulsions, such as soft-serve ice cream).
In mayo, the water comes in the form of the acid, (probably lemon juice), which is also one of the binders, (next to egg yolk, and possibly mustard), and the oil is, well, any cooking oil, really.
They require a large imbalance because of geometry. One of the two fluids is going to be contained in little orbs of which the surface is the emulsifier. The emulsifier usually has one end that likes polar molecules, and one end that likes non-polar molecules, but honestly, that’s an oversimplification when we’re talking about, ex: the proteins in egg yolks … honestly, it’s even an oversimplification when we’re talking about surfactants, because you can’t make something with mayo-like consistency from dish soap now, can you?
Anyways, we want those orbs to be as small and numerous as possible so that they end up squeezing the greater fluid between them so tightly that the orbs themselves can’t move much. To do that in a macroemulsion, (pretty much every culinary emulsion you’ll ever see is a macroemulsion, so don’t worry about microemulsions), we vigorously mix our lesser ingredient with the emulsifier and a similar amount of the greater ingredient.
Ie: you start your mayo with a squeeze of lemon juice, an egg yolk, and a tablespoon of oil.
And to get those orbs to stay small, we need to trap them in the aforementioned matrix, which means adding all the rest of the oil. But if we do that all at once, we run the risk of the orbs just breaking and separating our mixture into two layers, a process that is self-reinforcing once it starts, as the separating layers will sweep over the remaining orbs.
Ie: you pour your oil in slowly while continuing to mix, which both distributes the orbs throughout the oil, and continues to beat them down into smaller orbs
Now that we understand the science behind it, we can understand how to use an immersion blender to make mayo. We want a tall, thin container. We want to drop all of our ingredients in the bottom, and the oil on top, sink the blender all the way in, and mix. In this way, the emulsifier and acid will all mix only with the oil around them at first, and form a much thicker layer at the bottom that prevents the rest of the oil from just mixing in with it immediately.
Then, you just slowly lift the immersion blender out to slowly introduce more oil into the emulsion beneath it. The emulsion itself will control the rate at which oil can mix into it.
I don’t like this method, personally. For anything thicker than a vinaigrette, the immersion blender just doesn’t produce enough torque to mix the thick emulsion, and you just end up with, like, halfway-there mayo with oil sitting on top. You’re better off grabbing a whisk. (The aforementioned food processor is ideal, imo).
In any case, any recipe that just tells you to chuck it all into a blender, or mix it all with an immersion blender, without specifying any special technique, is just being lazy or worse, lying to make the recipe seem easier.
Not all emulsions can be very thick. (Talking about oil/water emulsions:) If the emulsifier isn’t very self-repellant, (A property strongly related to HLB, which is really just a breakdown of what percent of the molecule by mass is hydrophilic), then you need more emulsifier for less oil and less water at a ratio closer to 1:1, which is not going to produce as tightly-bound a matrix. For example, a true aioli, (ai = garlic, oli = oil), is just garlic, lemon juice, salt, and oil, (or, as my first cooking teacher would say, <<Le jeune de l’oeuf touchez PAS l’aioli!!>>), and it never does get as thick as mayo. Garlic is just not as good an emulsifier as egg yolk. It’s also *very* strongly garlicky, so the current trend of calling “mayo that happened to meet a garlic clove once upon a time” as “aioli” is one that I find disingenuous at best. A proper aioli is strongly garlicky enough that it tastes spicy hot! It’s not even in the same category!
I digress. Anyways, emulsions be tricky, yo.
Here is some fantastic FOOD SCIENCE as to what’s happening in that food processor. (Also yolk in french is “jeune de l’oeuf”? Literally ‘young of the egg?” Amazing.)
