How to Cook with Citric Acid, According to a Pastry Chef

Throughout her video cooking series Pastries with Paola, pastry chef Paola Velez has shared all kinds of delicious treats, from Hummingbird Cream Puffs to Black and Ruby Cookies. If you've been following along, you might have noticed an ingredient she uses to give dishes extra oomph — citric acid. It brings brightness to her Italian Buttercream, adds tang to the coating for Tamarind Jelly Candies, and also gives the candied oranges on this cake a sour twist. She calls the ingredient "a game changer." But if you've never worked with it, you probably have some questions about where to start. Velez shared her tips for cooking with citric acid, and explained why it's a key ingredient to have in your pantry.

First: What Is Citric Acid?

Citric acid is a weak organic acid found in citrus fruits, as well as other produce. It has a sour flavor — which is why fruits like lemons have their signature pucker. Velez describes it as "what is on Sour Patch Kids." While naturally occurring citric acid is found in citrus fruits, Velez and other chefs buy it in powdered form to use in their cooking. In addition to giving food a sour pop, it is also used as a preservative (more on that in a minute), and can even cause ingredients to change color.

Is Citric Acid Bad for You?

Per the Food and Drug Administration, citric acid is "generally recognized as safe when used in accordance with good manufacturing or feeding practice," and is "used in food with no limitations other than current good manufacturing practice." But when using it, stick to small quantities, and don't ingest it straight-up.

"If somebody's like 'I want to try citric acid,' and they grab a spoonful, that's a bad idea," Velez explains. "It can weaken the enamel of your teeth. It can hurt and make your tongue really sensitive if you do it too much, which is why I only use it in combination with something else. And even then, when I use it as its own thing with sugar, it's a very small, small quantity."

Within those guidelines, Velez says the amount you use is a matter of preference — you might want a stronger sour flavor, or something subtle. Since different batches of citric acid can vary in strength, she typically starts by adding a pinch to sugar, tasting it, and then adjusting the amounts until she's satisfied with the ratio.

Where to Buy Citric Acid

You can buy citric acid on sites such as Amazon and WebstaurantStore, in the canning section of stores, and also at natural food markets. Velez buys hers at Mom's Organic Market, where it's available both pre-packaged and in bulk.

Generally, she says citric acid has a pretty long shelf life. Check the expiration date — if you're not sure if your citric acid is good, she suggests tasting one or two granules. If they taste weak, buy a new package.

How to Cook with Citric Acid

Temper Sweetness and Boost Sour Power

Velez says her favorite way to use citric acid is to add what she calls "little hints of surprises." Take her Banana Pudding Paletas. The pinch of citric acid she adds to the custard that serves as the paleta base balances the sweetness in the bananas and vanilla wafer cookies, while it intensifies the tanginess of the ice cream. She also explains that you can use it to enhance the existing sour flavor of an ingredient, like tamarind, and boost the acidity and turn up the brightness when working with acidic ingredients like lemons.

Use it as a Preservative

Citric acid is used as a preservative to help prevent bacterial growth in jam and other canned food. For example, in this recipe for Canned Tomato Passata, the citric acid helps decrease the pH levels of the tomatoes and make the passata safe to can.

"It inhibits any kind of bacterial growth. You use it typically when you are making jam; you put it into the jam itself when you're about to can anything," Velez says, "and it just stops [the] bad microbes that want to ruin your delicious summer jams."

Brighten Up Your Food — Literally

Citric acid can help make the color of a dish more vibrant. An example Velez gave was cooking with prickly pear — if you find it's turned an unappealing "light pink-gray tone," adding a little bit of citric acid returns it back to the bright pink you expect. "We all kind of eat with our eyes nowadays, and we definitely eat with Instagram," she notes. Similarly, if you're blending an herb oil or making pesto, a pinch of citric acid will help preserve the herbs' green hue.

Citric acid is also what causes butterfly pea flower tea to turn from blue to purple in drinks. As our Executive Wine Editor, Ray Isle, demonstrated, once the butterfly pea flower tea interacts with the citric acid — whether in the form of lime juice or lemonade — the color-changing magic occurs. Velez says adding citric acid in these cases isn't about the flavor, but more so to get a "really fun, bold look" without using food coloring.

Try it Out

Now that you're briefed on citric acid, start cooking and see what it can do; Velez encourages experimentation. Try adding a pinch to a smoothie for brightness, using it to boost your cranberry sauce for Thanksgiving, or playing around with it in different desserts, like a cookie. Per Velez, "the possibilities are endless." If you aren't sure where to start, she suggests making a batch of something like cake batter and dividing it into smaller portions so you can test out proportions.

Try Velez's recipes — Banana Pudding Paletas, Italian Buttercream, Olive Oil Cake with Buttercream Frosting and Sour Candied Oranges, and Tamarind Jelly Candies — as well as these Kumquat-Riesling Gummies from Food & Wine's Paige Grandjean and Spicy Yeast Salt from chef Dave Beran.