The words for “starch” and “strength” are the same in the German language because they share a common goal: To add structure. Like an hour spent at the gym (or so they say), starches thicken, solidify, and add firmness to the body—in this case, the body of a sauce or a soup. Similarly, they can be used to tighten up the crispy coating of fried treats from vegetables to buttermilk chicken, drawing out water or other liquids and allowing for an even coating of batter or breading. But how do sticky starches stack up against flour? Read on for a full debrief on everything there is to know about the classic thickening agent.

How Starch Works

Starch is a complex carbohydrate that is present in organic matter from around the world, and the most common source of cooking starch is found in plants such as rice, sweet potatoes, corn, and more. Formed during photosynthesis, starch allows plants to store glucose—it’s what keeps sweet potatoes sweet, for example.

In cooking, starch takes the form of tiny granules to which water, broth, or other liquids bond. As the starch absorbs liquids, the liquid thickens, which is why starch is the secret behind a perfect pie filling or custard. However, if starch grains are added to cold liquid, they often sink without thickening the broth because heat is critical to cooking with starch.

As its temperature rises, a liquid bonds more readily to starches. This process is called starch gelatinization, which describes how starches swell and become more viscous in hot liquids—this is why store-bought pasta becomes soft and tacky when placed in boiling water

Typically, most starches should be dissolved in cold, warm, or simmering liquids and broths, as adding them to already boiling pots can trigger the gelatinization before the starch granules are evenly distributed. If starches aren’t evenly distributed, clumps form in what should be a smooth sauce or soup. However, sifting starch into a boiling liquid can help more evenly distribute the granules without creating clumps, or simply dissolve the starch into a small amount of water before adding it to a cooking liquid.

Starch vs. Flour

Flour is the classic thickener when it comes to cooking. From rouxs to stews to gravy, many people have historically opted to use sifted flour in a pinch for richer, more developed textures. So what’s the difference between using flour and starch? In some cases, there really isn’t much of a difference: For many recipes, starches and flour can be used interchangeably without a drastic effect. The key distinction is that while cooking starches are pure granules extracted from organic matter, flour is composed of a number of different proteins including gluten.

How to make an all-rounder roux

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Commonly used starches made from corn, potatoes, and tapioca are generally gluten-free, and can be used to accommodate a range of dietary restrictions. Similarly, most commonly used starches are flavorless, whereas flour has a distinct taste that may need to be masked.

5 Handy Ways to Use Starch

1. As mentioned before, starches are a quick and effective way to thicken a sauce. It’s the key to a creamy casserole, a pan of macaroni and cheese, or a silky gravy. Be sure to mix the starch with a bit of water before incorporating it in a larger saucepan to avoid thick clumps from forming.

Homemade pot roast and gravy

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2. Lock the moisture in by rolling meats and vegetables in starch before placing them in the fryer. The starch grains draw and retain moisture as the food starts to heats up, but as the hot oil wicks away any water from the gelatinized starch, it forms a crisp, taut coating with the perfect crunch.

Korean fried chicken with cucumber salad

Korean fried chicken with cucumber salad

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3. For crisper fried chicken or fish, blend starch into the breading or batter mixture just as one might incorporate flour. The flavorless coating will help keep your meat tender and juicy while it develops a golden-brown coat

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4. A custard should be rich, creamy, and stay true to its base flavors. Use starch instead of flour to stiffen watery custards and puddings for a flavor-neutral thickening agent.

Homemade vanilla pudding

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5. A perfect pie or tart balances a buttery crust with a fruity but firm filling. Fold the starch into the filling for a sturdy compote that’s ready to bake.

Sour cherry pie

Sour cherry pie

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Types of Starch

When it comes to finding the right starch, gluten-free bakers have mastered the craft. Sourced from corn, tapioca, potatoes, and arrowroot, each starch offers a different set of strengths, and bakers have worked for years to fine-tune the nuances of each type.

Cornstarch is perhaps the most popular starch for cooking. Derived from the corn kernel, this starch is incredibly versatile and can often be substituted in for other starches. Tapioca starch offers a similarly broad palette of opportunities. Made by pounding cassava root into a fine powder, tapioca starch acts as a simple thickening agent without changing the flavor or texture of a dish.

Potato starch is another common option for chefs, bakers and fry cooks alike. Due to its low gelatinization point, this starch dissolves evenly without high temperatures and can be used for simmering soups or sauces.

Pumpkin gnocchi with sage butter, walnuts, and smoked bacon

Pumpkin gnocchi with sage butter, walnuts, and smoked bacon

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Arrowroot powder is the last of the common kitchen starches. It can be made from a number of tropical rhizomes–creeping roots that grow underground–and is particularly helpful when thickening acidic liquids and broths. Arrowroot powder can be cooked to make clear, viscous liquids, and is particularly handy when preparing sauces for East and South Asian meals.

Bavarian cream with raspberry sauce

Bavarian cream with raspberry sauce

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Starch Alternatives

Barring dietary restrictions, flour can be substituted in for starch in a pinch. The common conversion is 3 tbsp of flour for every 1 tbsp of starch required. Unlike most starches, flour is not flavorless, so spice and season as needed!

What are your favorite things to do with starch? Do you have a favorite recipe that you would like to share with us? Tell us in a comment or upload it to our app to share it with our global community!

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