What do silky vinaigrettes & restaurant-quality pasta sauces have in common? They are both molecular marvels: homogenous mixtures of things that actually… don’t mix. "Delicious foods" are delicious because of the way that different flavor compounds engage specific taste receptors on your palate - and some of those flavor compounds are fat-soluble, while others are water-soluble. The more compounds a food has, the more receptors it stimulates while you eat it, and the more flavorful, complex, and enjoyable that dish tastes to you. It's famously known that water and oil don't mix, but in so many instances we need to utilize both mediums when we cook to maximize flavor. Not only that, but water is nearly omnipresent in food, and we are biologically predisposed to crave fats and to feel satiated by their texture and mouthfeel; in short, we want both, and we need both. So, oil & water: we can't live without 'em, but they can't live together - or can they? Enter emulsifiers: the peacemakers of your culinary arsenal.
Here to learn more? Awesome: the read below should take you about 6 minutes. Just wanna get to the recipes? No sweat: skip the science and scroll straight down to the recipes, attached as separate files for your saving and printing pleasure. xo.
We're going to talk about emulsifiers in a very broad and generalized sense, mostly because this is a huge and actually very complicated subcategory of culinary science - an exhaustive version of which you would not want to read and which I'm not qualified to write. But: understanding the simplest explanation of what an emulsifier does, which common ingredients are emulsifiers, and why it's worth understanding and utilizing them in your home kitchen is something [I think?] we can do in just a page. Let's go.
OK: What is an emulsifier? It's a substance that stabilizes an emulsion, which is a homogenous mixture of two liquids that are otherwise immiscible (un-mixable) - and a homogenous mixture is a mixture that is uniform throughout: no pockets of imbalance, no clumps, no lumps. So, an emulsifier is something that forces two un-mixable liquids to mix - and keeps them that way. It is, in short, a peacemaker.
Simple enough, but why do we need to create this peace? Imagine a bottle of salad dressing. Everyone has seen and used bottled vinaigrettes that had to be shaken - vigorously! - before they were poured. Why did we have to shake it? Because the water and oil had separated: they are immiscible. If we were to pour without shaking, the oil that floats at the top of the bottle would pour from the vessel first - leaving us with a slick, greasy, under-seasoned salad, because none of the aromatics, acids, salt, or other water-soluble flavor compounds were suspended within the dressing; those had all separated to the bottom, beneath the oil. And we don't want that, so, we shake.
“What's the big deal?,” you ask. “It’s just a little shake action.” I don't mind it either, and you're right: the shaking is not the problem; we are not embracing emulsification solely to spare ourselves the 6 seconds of table-side shaking. The separation is the problem. Ever passed that bottle of dressing around a crowded table? Everyone has to give it the shake. That's because that dressing - that unstable mixture - is not emulsified, and it is starting to separate almost immediately. And that's happening to the dressing that has left the bottle, too: it's separating on your salad. The oil will cling to the leaves, but the water will start to slide off - and take those flavor compounds that we discussed with it, straight to the bottom of the bowl. If you are eating a salad and it is dressed with a non-emulsified dressing of oil and water, then you are going to wind up with drastic flavor and texture imbalances. Separation is almost guaranteed to occur, and that separation means pools of oil, clumps of aromatics, puddles of vinegar or lemon juice; no cohesion, no balance. And cohesion and balance just taste better.
All of this wordiness is not just for the sake of improving your salads; vinaigrettes are far from the only instance of emulsification in our kitchens - they just easily illustrate the point pretty well. But if you’ve ever attempted to make a custard, or cheese sauce, or Hollandaise, or mayo - all emulsions! - and had the mixture “break” on you, you understand: when oil and water should be bound together, and aren’t, it’s a mess. What’s more, not only is the broken mixture often unpalatable, it can even be damaging to the rest of your dish. Imagine a marinade for chicken or a quick pasta sauce that each include lemon and olive oil: if we don’t bind that oil and water (in this case, the “water” is citrus juice) together, not only will the final product have an imbalance of flavor because those main components aren’t evenly distributed across each bite, you will also be exposing your raw protein or your cooked pasta to an acid that’s untempered by fat - and acid denatures the structures of animal and wheat proteins, causing them to break down and leading to patches of mushy chicken or pasta. Emulsification matters.
A lack of emulsification doesn’t always mean you’re serving bad food. But it does mean you’re not serving the best version of that food. So let’s fix it. Let’s take the extra minute or two to utilize the emulsifiers.
The list of known culinary emulsifiers is long (if you’re one to read labels, that’s what all of those gums and lecithins are doing) but for the sake of the home cook, there’s a handful that cover most of our needs: egg yolks, mustard, and starch (usually from cereal grains). (Sidebar: starch is actually not a true emulsifier on its own, but it will form a gel when mixed with water and this gel has both thickening and emulsifying properties. This one deserves a heftier explanation, but I swear I am actually trying to keep this as short as possible.) Egg yolks contain a large amount of lecithin, and mustard seeds have a lot of mucilage - and both of these substances are molecularly amphipathic: hydrophilic (loves water) on one end, and lipophilic (loves fat) on the other. In other words, each molecule of lecithin or mucilage holds hands with water AND oil, linking them together where they otherwise would refuse. I have created this very accurate visual representation to illustrate this point.
(See? Science.)
Once you’ve introduced an emulsifier to your recipe - be it a vinaigrette, a pasta sauce, a mayonnaise - it’s very, very easy to get the emulsifier to do the work of binding your other ingredients together: you just need to vigorously mix. That constant movement of ingredients around a cooking vessel (a bowl, a pot, the jar of a blender or food processor) ensures that you’re introducing every molecule of emulsifier to every molecule of oil and water, and the emulsifier needs no more introduction than that: as soon as its hydrophilic parts meet water, and its lipophilic parts meet oil, it’s going to grab hold. You’ll (literally!) be able to watch the mixture emulsify: the mixture will thicken and lose translucency in a matter of seconds.
I mentioned three common and relatively universal emulsifiers: egg yolks, mustard, and starch. Egg yolks are the glue that hold oil and water together in mayonnaise, but I’m not going to provide you with a recipe for it; homemade mayo is excellent, but store-bought mayonnaise is very good - so good that I rarely feel compelled to do the work of making my own (if you need a recommendation: Duke’s, kewpie, and Hellman’s/Best Foods are reliably A+). Eggs are also used to emulsify and stabilize custards, which form the base of a little something called “ice cream,” and that’s a newsletter unto itself (coming in a few weeks!), so: no recipe for that either. Instead, I’m including two recipes this week that utilize mustard and starch, respectively, to emulsify their components. The vinaigrette document below is actually less of a recipe than it is a formula: a standard ratio of ingredients for success that you can manipulate to your hearts’ content, and not just for the sake of your green salads - let that guide inspire and improve the dressings for lentil and grain salads, marinades for raw proteins, sauces for grilled vegetables and meat, dipping sauces for dumplings, whatever.
And the second recipe is for… buttered noodles. Don’t leave! You’ve made it this far, so hear me out. I know that buttered pasta feels pedestrian, but if some of the most talked-about recipes during the pandemic have been for Cinnamon Toast (paywall) and Broccoli Delight, then why can’t we make this A Thing, as well? A bowl of warm noodles sauced with quality butter is sublime on its own, but what’s more, this recipe is a launchpad to other more nuanced dishes, a starting point for better pasta of all kinds. If you think that buttered noodles are nothing more than the eponym suggests - just butter, and noodles - then please, don’t skip this one; we’ll harness the emulsifying properties of wheat starch to make a restaurant-quality glossy, silky sauce in less than 5 minutes, and it’s a method that will elevate ALL of your pan-sauced pastas forevermore. Promise.
LINKS
If you want to learn more about emulsification, this Food Lab video is a great place to start. The creator of The Food Lab, J. Kenji Lopez-Alt, is a fantastic resource for all things culinary-science in general, and just this week he announced the upcoming release of his next cookbook “The Wok” - which I immediately pre-ordered. If you want to do the same, click here to support your favorite local bookstore while doing so (and if you don’t have a favorite, then please support mine - White Whale Books!).
While you’re at it, there’s another (hopefully!) great pre-order available: a cookbook from the family behind Red Boat Fish Sauce. I can’t wait for that one. We still have a few months to pass before either of those books ship, however, so in the meantime, pick up a bottle of Red Boat and make this non-traditional (but great) take on Yum Nua from Butter’s Instagram account. If you do, let me know how it is.
READER Q’s
“What’s your favorite butter?” - J.L., Ohio
Kerrygold. Good grass-fed fats, nice salt content, not too sweet or too savory, bakes really well. I buy a lot of different butters for different things (and just for the sake of trying them), but Kerrygold performs reliably pretty much everywhere: cake, toast, pan sauces, veggies. I had high hopes for the new Costco house-brand of grass-fed butter but the more I use it, the less I like it; it feels quite waxy. And yes: I do always buy salted butter. We can argue about it later.
“Do you have a favorite kitchen gadget or tool? I want to treat myself to something new.” - L.C., Pittsburgh
Not a creative or shocking answer, but I can’t live without good knives, and a Misen is an excellent purchase: really affordable, holds a great edge, and isn’t as heavy as other German-style knives. Also love their non-stick pans. Other things I use every single day: a good immersion blender; this incredibly perfect silicone measuring set (and I HATE silicone cookware otherwise); rubber spatulas and coated tongs (I have a dozen of each). My current dream splurge: a massive (like, 2’x3’) custom maple cutting board/butcher block.
RECIPES