Sour Cream Makes for a Better Egg Wash Than an Actual Egg

There are times when eggs are non-negotiable in a recipe—like egg drop soup or quiche—but when eggs play a minor role, then why not use a replacement? Egg wash is a prime example. Using it adds color and shine to finished baked goods like dinner rolls and pies, but when eggs are selling at a premium price, it’s hard to justify using an egg wash at all.

Finding a good egg wash alternative isn’t only useful for saving a buck, but it can be a handy back-up even when eggs are plentiful. There’s always the occasion where you just ran out, or you have folks coming over that are on egg-free diets. After some browsing on the internet, butter, mayo, milk, heavy cream, maple syrup, and sour cream seem to be the common substitutes.

Credit: Allie Chanthorn Reinmann

I whipped up a batch of my favorite biscuits and painted them with different finishes so I could compare them after baking. You can see in the picture above that there are eight biscuits. In addition to the six alternatives I mentioned, I did one with actual egg wash so we can track what we're striving for, and one with absolutely nothing on it as a control.

25 minutes later, the results were in and I was actually pretty surprised. Each topping produced a different result; some more obvious than others. When egg wash is used as a topping (as opposed to a binder), its primary function is to impart color, shine, and leave no trace of flavor, so that's what I was looking for.

Credit: Allie Chanthorn Reinmann

Here are the results from top left to right, and bottom left to right.

• Egg wash: Goal browning and shine

• Sour cream: Best browning, high gloss (outshined the egg)

• Heavy cream: Light browning, a slight shine

• Whole milk: Well-browned, slight shine

• No wash: Light browning, matte

• Maple syrup: Well-browned, no shine

• Mayonnaise: Medium browning, medium shine

• Butter: Light browning, no shine

Hands-down, the winner was sour cream. Dare I say it performed even better than the actual egg wash. (I tried to capture the blinding shine in the picture below.) The color of the baked sour cream coated biscuit was a beautiful dark brown, and the shine surpassed even the egg wash standard. 

Credit: Allie Chanthorn Reinmann

Runners-up were mayonnaise and whole milk for their middle-of-the-road performance in both categories. For a vegan option, maple syrup imparted gorgeous brown coloring, but it had a decidedly un-shiny finish and it leaves behind a subtle sweet flavor (which might be good or bad depending on your preferences). 

Butter turned out the worst performance. I would be sad, but I’ve been fooled by butter before so I was expecting the disappointment. On both counts, the finish paled in comparison to its competitors. Butter aside, at least you have some options for the next time you make a batch of biscuits, rolls, pastries, or pies. Save the eggs for when they matter most.