Soy Flour vs All-Purpose Flour: Full Details

In today’s flour showdown, we’ve got soy flour vs all-purpose flour.

On one side, we have the versatile, all-purpose flour that has been a staple in kitchens for centuries. And on the other, we have the up-and-coming soy flour, a plant-based alternative that has been gaining popularity in recent years. So, who will come out on top? Will it be classic all-purpose flour, or will soy flour shake things up? Let’s find out!

Comparing soy flour vs all-purpose flour

	Soy flour	All-purpose flour
Substitution ratio (vs all-purpose)	3:10	N/A
Gluten-free?	Yes	No
Keto-friendly?	Somewhat	No
Paleo-friendly?	No	No
Common Allergens	Soy	Wheat, gluten
Liquid absorbency	High	Medium
Pantry shelf life (unopened/sealed)	5 months	6-8 months
Best for	Breads and baked goods like cakes and donuts; also candy, fudge, pancake mix, frozen desserts, and pasta; thickener in sauces and soups	Non-yeast recipes (think cookies, biscuits, and some breads)

Soy flour can be substituted for up to 30% of the all-purpose flour in a recipe without making any other adjustments. For example, if a recipe calls for 2 cups of all-purpose flour, you can substitute up to 2/3 cup (or approximately 10 tablespoons) of soy flour without making any other adjustments.

However, it is important to note that soy flour is high in protein and may absorb more liquid than all-purpose flour, so you may need to add extra liquid to the recipe or decrease the amount of soy flour used.

Differences between soy flour and all-purpose flour

Soy flour and all-purpose flour have several distinct differences. 

First off, soy flour is gluten-free, while all-purpose flour is not. Soy flour is made from soybeans, which are a type of legume, so soy flour is not paleo-friendly, but is somewhat keto-friendly as it’s lower in carbs (and higher in protein) compared to wheat flour.

Soy flour has a distinct flavor that can be described as nutty or earthy, which can be desirable in some recipes. All-purpose flour, on the other hand, has a neutral flavor that is not as noticeable in baked goods.

Baking with soy flour vs all-purpose flour

As mentioned above, soy flour is much higher in protein and more absorbent than all-purpose flour, which means that baked goods made with soy flour tend to be denser and heavier than those made with all-purpose flour, so soy flour may not be suitable for recipes that require a light and fluffy texture.

Since it’s gluten-free, soy flour can be more difficult to work with, as gluten helps to provide structure and elasticity to baked goods.

Soy flour can be used in a variety of baked goods, such as bread, muffins, and pancakes, but I generally recommend using it in combination with wheat flour or other flour, rather than as a 1:1 replacement for all-purpose flour. 

Ingredients in soy flour vs all-purpose flour

Soybeans are the main ingredient in soy flour and wheat is the main ingredient in all-purpose flour. 

All-purpose flour may also contain additives such as malted barley flour, niacin, iron, thiamin mononitrate, riboflavin, and folic acid. These additives are added to enrich the flour with additional nutrients.

Some brands of soy flour may also contain additional ingredients such as preservatives or fillers, so it is important to check the label to ensure that you are getting pure soy flour.

Soy flour + all-purpose flour nutritional facts

Per ¼ cup	Soy flour	All-purpose flour
Calories	100	110
Carbs (g)	10	23
Fiber (g)	5	1
Fat (g)	0	0
Protein (g)	15	4
Glycemic index score	25	85

Soy flour is higher in fiber and MUCH higher in protein than all-purpose flour. Soy flour typically contains around 40% protein, while all-purpose flour contains around 10% protein. This makes soy flour a popular choice for those following a high-protein diet.

Soy flour also has a much lower glycemic index of 25, making it a good choice for diabetics. (Not as good as almond flour, but still very good!)

However, due to its high levels of phytoestrogens, eating too much soy flour could potentially be related to nutrient deficiencies, digestive issues, and thyroid problems. I recommend eating soy flour in moderation, and of course, please consult with your doctor before adding soy flour to your diet if you have health concerns.

How to store soy flour vs all-purpose flour

Soy flour and all-purpose flour should be stored in airtight containers and in a cool, dry place such as the pantry or cupboard.

Unopened, soy flour lasts around 5 months. Due to the oils in it, soy flour can go rancid quickly, so it is best to store it in the refrigerator or freezer for long-term storage (up to 1 year). All-purpose flour, on the other hand, can be safely stored at room temperature for 6-8 months.

Final thoughts

The choice between soy flour and all-purpose flour depends on personal preferences, dietary needs, and desired outcome. Soy flour has a higher protein and nutrient content, is gluten-free, and has a distinct nutty flavor. All-purpose flour, on the other hand, has a neutral flavor and is extremely versatile. While soy flour can be a good choice for baking, it may require some experimentation and adjustments to achieve the desired texture. Ultimately, experimenting with different combinations of flours may be the best way to achieve the desired outcome in your baking! There are 50+ different flours to choose from!

FAQ