Can You Substitute Baking Soda for Cornstarch?

At first glance, they look the same. White powder, pantry staple, some dusty box in the back of your cabinet that hasn’t moved in years. Cornstarch. Baking soda. Two household ghosts. And yet, in a pinch, people start asking the survival question: If I run out of cornstarch, can I just swap in baking soda?

On the surface, it sounds harmless. After all, they’re both cheap, shelf-stable, and multipurpose. But here’s where the trap lies: food science—and the food industry that loves to keep you confused—doesn’t forgive ignorance. So let’s strip away the “all powders are the same” myth and dig into what’s really happening when you play substitution roulette.

Cornstarch: The Silent Thickener

Cornstarch isn’t flashy. It doesn’t fizz, it doesn’t foam, and it won’t ruin your Sunday biscuits if you use too much. Its job is simple: when it meets heat and liquid, it turns thin soups into thick stews, runny fruit fillings into glossy pie centers, and watery gravies into something you’d actually want to eat.

Think of cornstarch as a survival glue for food. It binds water, holds textures together, and makes meals look and taste complete. It’s not about flavor—it’s about structure.

And here’s the kicker: cornstarch is so neutral, it plays nice with nearly any dish. That’s why it’s the go-to for stir-fries, pie fillings, and even powdered sugar blends. It doesn’t fight the flavor profile—it just makes it better, thicker, and more consistent.

Baking Soda: The Quiet Saboteur (Unless You Use It Right)

Now, baking soda is a different beast. It’s not a thickener at all—it’s a chemical reactor. Mix it with an acid, and suddenly you’ve got bubbles of carbon dioxide rushing through your dough, puffing it up like a balloon.

Sounds harmless, right? Until you dump baking soda into a recipe expecting cornstarch’s smooth thickening magic. Spoiler alert: you won’t get a silky sauce—you’ll get a bitter, alkaline mess with an aftertaste that could strip paint.

The bigger danger? Once baking soda reacts, you can’t undo it. It either works perfectly in balance with acid, or it backfires spectacularly. In other words: baking soda is a demolition charge, not a construction beam—you don’t “swap” it, you deploy it with intent.

The Illusion of Substitution

Here’s the ugly truth: food companies love lumping pantry staples into a single aisle, leaving you to guess what they actually do. Flour, cornmeal, cornstarch, baking powder, baking soda—all in boxes that look like they were designed in 1953. And that confusion? It works in their favor. Wasted ingredients mean more sales.

So no, baking soda cannot replace cornstarch—not in gravies, not in pudding, not in pie fillings. Trying to force it is like using gasoline in your water filter. Wrong tool, wrong result, wrong mindset.

And when you’re in a crisis—whether that’s a blackout, a lockdown, or just a busted supply chain—you don’t get second chances. The illusion of substitution isn’t just a kitchen fail—it’s wasted calories, wasted resources, and one step closer to desperation.

What You Can Use Instead of Cornstarch

Here’s where the real prepping mindset kicks in: substitutions that make sense. If you’re out of cornstarch, you don’t need to panic—you just need to think strategically.

Arrowroot Powder – Pure, clean thickener. Works almost exactly like cornstarch but leaves sauces a little shinier.
Potato Starch – Neutral flavor, great for soups and stews.
Tapioca Starch/Flour – Works wonders in fruit fillings, pies, and desserts.
All-Purpose Flour – Old reliable. It won’t give you the same glossy finish, but it’ll thicken in a pinch.

The point here is control. Every one of these substitutes is a thickener by design, not a chemical wildcard. That’s the kind of pantry logic that keeps you steady when resources get tight—you don’t gamble, you plan.

Where Baking Soda Belongs

Don’t throw your baking soda box in the trash—it has its own survival credentials. Just not as a cornstarch impersonator.

It keeps your fridge from smelling like death.
It cleans pots, pans, and even teeth.
It neutralizes acid and helps dough rise.
It can even put out small grease fires.

Related: Baking Soda – 112 Uses (WWII Series)

But here’s the reality: baking soda’s role is reactive. It’s a firefighter, not a builder. That makes it invaluable in certain scenarios but catastrophic in others. Respect its power, but don’t expect it to play cornstarch’s role—it was never meant to.

Final Thoughts: Know Your Tools, Outsmart the Chaos

In a survival kitchen—or just a Tuesday night when the store’s closed—you need to know which ingredients are allies and which are impostors. Cornstarch and baking soda might look like twins, but one’s a builder and one’s a reactor.

So the answer is clear: No, you cannot substitute baking soda for cornstarch. Not if you want food that tastes edible, not if you want your prepper pantry to actually serve you in a crisis.

Remember—knowledge is survival. Don’t let confusion sabotage your plate, your pantry, or your peace of mind.