How to Make Oat Flour: 3 Methods for Gluten-Free Oat Flour

Oat flour is a whole-grain, gluten-free flour option for those who prefer or require a gluten-free diet or have celiac disease (a severe gluten intolerance). Gluten-free baking recipes call for a gluten-free flour, such as oat flour, almond flour, coconut flour, or a blend. Additionally, combining tapioca starch or potato starch with oat flour adds structure to gluten-free baked goods, similar to the structure all-purpose flour or wheat flour imparts.

Oats are naturally gluten-free, but look for certified gluten-free oats if it’s important to you they come from a gluten-free factory. Store homemade oat flour in an airtight container in a pantry with other dry baking ingredients.

Oat flour adds a nutty flavor and hearty texture to baked goods and other foods. Consider these three ways you can use homemade oat flour at home:

1. 1. Add oat flour to baked goods. You can make brownies, waffles, banana bread, chocolate chip cookies, and oatmeal cookies with gluten-free oat flour. Use baking recipes specifically for gluten-free baked goods. A cup of oat flour and a cup of regular flour possess different properties; hence, it can be challenging to substitute oat flour for regular baking ingredients.
2. 2. Make oat milk with oat flour. Blend oat flour with water until the mixture is creamy and thick. Using oat flour instead of whole oats produces a smoother oat milk that requires little to no straining. This can be a good way to use leftovers from oat flour recipes.
3. 3. Stir oat flour into soups. Use oat flour instead of a roux or cornstarch slurry to thicken soups and stews. Whisk in dry oat flour or mix it with water to create a paste. Either way, constantly whisk the soup to prevent lumps.

Various oats undergo different levels of processing, but you can use all types of oats to make oat flour. Here are three styles of oats that will work for oat flour:

• Old-fashioned rolled oats: Also known as rolled oats, old-fashioned oats undergo light processing that involves removing the husk from groats, steaming the oat, rolling it flat, and lightly toasting it. This means when making your own oat flour with old-fashioned oats, you can skip the toasting step. Bakers commonly use old-fashioned rolled oats for oatmeal cookies and crumb toppings.
• Quick-cooking oats: Also known as instant oats or quick oats, quick-cooking oats grind into a fine powder well since they are thinner than rolled oats. This is the most processed type of oats you can use to make oat flour.
• Steel-cut oats: These oats are harder and require a longer cooking time in oatmeal recipes; however, making oat flour from steel-cut oats produces a hearty flour with good texture. To make steel-cut oats, manufacturers cut groats into two or three pieces.

Oats range in texture from soft to crunchy, but you can use any of these three appliances to reduce oats to a fine flour:

1. 1. Coffee grinder: Reserve a grinder solely for making oat flour to ensure it remains gluten-free and for purity of flavor. Alternatively, clean a coffee grinder well to remove any leftover coffee grounds or spice powder. Add a few tablespoons of oats at a time to a coffee grinder or spice grinder. Gently shake the grinder a couple of times as it grinds the oats to aerate the flour and make sure each oat goes through the blades.
2. 2. Food processor: Pulse the oats a few times in the bowl of a food processor to break up the oats. Then process the oats at normal speed until the oats turn into a fine powder. Avoid overprocessing the oats, as the release of their natural oils will cause clumps to form.
3. 3. High-speed blender: Add the oats to a high-speed blender pitcher and secure the lid. Keep the blender’s percolator on hand to keep the oats moving while they blend. As with a food processor, blend the oats until they break down into a fine powder but before clumps form.

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