Tofu, also known as bean curd, is a food prepared by coagulating soy milk and then pressing the resulting curds into solid white blocks. Tofu is an incredibly versatile ingredient that can be used in both savory and sweet dishes. It’s a staple food in many Asian cuisines and valued for its high protein content and meat-like texture when prepared correctly.
But what kind of bean makes the best tofu? There are a few key factors that impact tofu texture and flavor:
Soybean Variety
Not all soybeans are created equal when it comes to tofu production. Certain soybean varieties have been selectively bred to produce optimal tofu texture and yield. The most prized soybeans for tofu production include:
- Vinton 81 – This Iowa State University bred variety has excellent tofu processing characteristics including high protein content, large bean size, and light hilum color.
- Beeson – Another U.S. variety valued for tofu production. It has high protein, good agronomic traits, large seeds, and white hilums.
- Enrei – A popular Japanese variety bred specifically for tofu. It produces a very smooth, tender tofu texture.
These varieties have the right balance of seed size, protein levels, and low lipoxygenase content to produce premium tofu.
Soybean Growing Conditions
The climate and soil conditions where soybeans are grown impacts the chemical composition of the beans, which in turn affects tofu quality. Cooler regions produce harder, drier soybeans while warmer equatorial regions produce softer, oilier beans. The minerals in the soil also influence the final soybean composition. Soybeans grown in magnesium-rich soils produce softer tofu. Overall, soybeans grown in the midwestern and northern U.S. tend to produce firmer tofu than those grown in the south.
Soybean Storage
Freshly harvested soybeans make the best tofu. Aged soybeans degrade in quality, producing lower protein yields and poorer texture. Tofu manufacturers prefer to work with soybeans stored for less than 1 year and may contract directly with farmers to ensure freshly harvested crops. Refrigerated storage helps preserve soybean quality longer.
Soy Milk Extraction
The first step in tofu production is extracting soy milk from soaked, ground soybeans. The extraction method influences the flavor, aroma, sugars, and protein content of the milk. Tofu makers may employ different grinding, filtering, and boiling treatments to create their desired soy milk profile from which to make tofu.
Coagulants
Coagulants are added to hot soy milk to induce curdling and formation of tofu curds. Different coagulants produce different textural results:
- Nigari – Magnesium chloride concentrated from seawater. Nigari produces soft, smooth tofu.
- Calcium sulfate – The most common coagulant used in the U.S. It produces firm tofu.
- Glucono delta-lactone – A vegetarian friendly organic acid. It produces very smooth, tender tofu.
The choice of coagulant impacts the mineral content, flavor, and texture of the finished tofu.
Pressing and Molding
After coagulation, the tofu curds are pressed to remove liquid and condensed into a block shape. Longer pressing times result in firmer textures. Tofu can be pressed into varied shapes and sizes using different molds.
The Best Bean for Tofu
Taking all these factors into account, the consensus is that certain soybean varieties grown in the northern U.S. with minimal storage time produce the highest quality tofu. The large, high protein content of varieties like Vinton 81 and Beeson make them preferred for tofu production. Their lighter seed coat color also contributes to a whiter tofu color.
Enrei and other Japanese varieties are excellent as well, but less suited to growing conditions in most of the U.S. Northern grown soybeans tend to produce firmer textured tofu due to their lower oil content. Many Asian tofu makers prefer these firmer American-grown soybeans to produce pressed tofu with just the right consistency. The firmer texture also holds up better in soups, stir fries, and other wet cooking applications.
Both Vinton 81 and Beeson soybeans have excellent tofu making pedigrees and are considered the top varieties for artisanal and commercial tofu production in the U.S. Their high protein content and large but firm texture when milled produces premium soymilk curds and tofu with a desirable texture.
| Soybean Variety | Seed Characteristics | Recommended Use |
|---|---|---|
| Vinton 81 | Large seeds, high protein content, firm texture | Premium tofu production |
| Beeson | Large seeds, high protein content, firm texture | Premium tofu production |
| Enrei | Large seeds, high protein content, smooth texture | Silken tofu production |
Impact of Growing Conditions on Tofu Quality
Where the soybeans are grown geographically has a significant impact on their composition and tofu quality:
- Northern U.S. – Colder climates produce harder, drier soybeans resulting in firmer tofu.
- Southern U.S. – Warmer climates produce softer, oilier soybeans resulting in softer tofu.
- Mineral levels – Magnesium-rich soils produce softer tofu. Calcium-rich soils produce firmer tofu.
As a result, soybeans from Minnesota, Iowa, and Wisconsin are highly sought after for producing firmer pressed tofu. Their harder texture and lower oil content creates tofu with just the right consistency to meet the expectations of many tofu makers.
The cooler climate helps concentrate protein while limiting oil and carbohydrates. The end result is soybeans with the ideal composition for creating premium tofu. Soybeans from the upper Midwest have the right balance of large seed size, high protein content, firm texture, and light color that makes them a favorite for high quality tofu production.
Best Practices for Making Great Tofu
To maximize quality, tofu producers should follow these best practices:
- Select northern grown soybean varieties like Vinton 81 or Beeson.
- Use freshly harvested soybeans stored for less than 1 year.
- Refrigerate soybeans to preserve freshness.
- Carefully control soaking, grinding, boiling, and filtering to extract high protein soy milk.
- Use a coagulant like nigari or calcium sulfate to produce the desired tofu texture.
- Press tofu to achieve the ideal firmness based on application.
- Package tofu in water to maintain freshness.
Following these steps allows producers to achieve premium tofu texture, taste, and quality using the best American grown soybeans. With proper sourcing of beans and process controls, artisanal makers can craft firm tofu with a perfect consistency for any recipe.
Conclusion
The soybean variety and growing conditions have a marked impact on tofu quality. For optimal texture and taste, northern grown soybeans like Vinton 81 and Beeson are recommended. Their large seed size, firmness, high protein, and light hilum color produce exceptional soy milk and tofu. With care taken in every manufacturing step, these beans yield tofu with a perfect texture for cooking applications like stir frying, soup, salads, and more. Tofu lovers agree, when you start with the best soybeans you can taste the quality in every bite.