Fix Grainy Cheese Sauce With Just A Single Acidic Ingredient

There's nothing like a smooth, rich, velvety cheese sauce, such as Alfredo, queso, or mornay. But getting that sauce to the perfect consistency can be a struggle. Dairy-based sauces are notoriously tricky to perfect. They can break at a moment's notice, causing the sauce to become gritty and clumpy.

Stop short before you toss that broken sauce in the trash, though. There's a way to save gritty cheese sauces, and you likely already have it in your fridge: lemon juice. A squirt of lemon comes to the rescue of ruined sauces in a pinch. All you have to do is cool the broken sauce, add a tablespoon of lemon juice (or white wine, if you don't mind the flavor), and whisk vigorously.

This trick works best if you haven't already added acid to the sauce. Add too much acidity, and you might get the opposite effect of further breakage — balance is the key.

It's a great trick to know how to fix a broken sauce, but how do cheese sauces get grainy in the first place? Curdling can occur for a number of reasons, though it commonly happens when a sauce is overheated. 

Avoid cranking up the temperature while cooking. High heat causes the proteins in the cheese to become denatured, resulting in clumping. It's also why citrus helps fix the problem. Acids unwind the clumped-up protein molecules and prevent the sauce from seizing any further.

Still, overdoing the acidity can also trigger clumpiness, as well as quick temperature changes (such as taking cold cheese from the refrigerator and adding it to a simmering sauce base). Sauces can be delicate and should be treated as such. You want to gradually heat and cool your sauce to avoid dramatic temperature changes. Letting the cheese come to room temperature before adding the acidity will help prevent disaster.

On top of minding the heat and keeping the acidity balanced, there are a few extra steps you can take to prevent graininess in cheese sauces. First, grate the cheese as finely as possible before adding it to the pan. This helps the cheese melt more quickly, allowing you to simmer the sauce at a lower heat to avoid seizing.

Adding an emulsifier can also help deter problems in a sauce. Emulsifiers act as binders, making it much more difficult for proteins to clump and separate; this leads to a cohesive, silky sauce. You might have seen mustard as an ingredient in some cheese sauces and wondered why. It's not just for added flavor — mustard is an emulsifying ingredient, and a dollop in the sauce can go a long way towards keeping everything cohesive.

Don't fret next time your cheese sauce starts getting a little gritty. A splash of lemon juice will have it looking as good as new.