Introduction: Beans to Curds - the Making of Tofu

About: I am an 18-year-old student in 12th grade, I enjoy baking, running, programming, 3-D design, photography, and nature!

As a vegetarian, tofu has always been one of my favorites to eat and to cook with. Tofu can be cooked so many ways into so many dishes and I wanted to know how it was made. A while ago tofu seemed like something you could never make at home it was just something you bought at the store. However, I visited Twin Oaks and saw how they make it and watched my mom make it for me I was immediately intrigued. With some help from my mom and her resources, I now know how to make it and wanted to share my knowledge with everyone! Here is my guide on how to make the best tofu right in your kitchen!!

Step 1: Ingredients and Equipment

Ingredients for this recipe are pretty simple, you will need:

  • Filtered Water

You will also need the following equipment to make tofu:

  • Blender
  • Stainer
  • Large Bowl
  • Large Pot about 3 qts.
  • Smaller Pot about 2 qts.
  • A ladle
  • A wood spoon
  • Standard measuring tools

You will definitely need larger pots if you plan on making a larger batch!

Step 2: Soaking the Soybeans

In order to make tofu, you must first make fresh soymilk, to do that you must soak you soybeans overnight. To do this take your soybeans and rinse them in a strainer, make sure there is not any dirt or rocks (rocks are commonly found in dried beans, make sure to check any time you are cooking with dried beans). Once you have rinsed them place them in a large bowl and add two inches of filtered water. Let the beans soak overnight, but try not to soak them for more than 18 hours.

Step 3: Making the Soymilk

Before blending the beans add five cups of water to the large pot and set it on medium-high heat. Now that your beans have been soaked, rinse them again in a strainer and then put them in a blender. Then add two cups filtered water to the blender and begin to blend it, blend for at 2 minutes to make sure to grind up all whole beans. Once the pot of water is boiling then add the bean puree to the water and mix it in. Continue to stir the pot for 3-6 minutes until the foam starts to rise similar to a beer or soda (see the fourth photo) then remove from heat. Meanwhile, place the cheesecloth in the strainer inside a bowl to catch the soymilk, twist the top of the cloth and squeeze out as much liquid as you can. You can discard the lees (the solid mush), you will only need the liquid soymilk in the next steps.

Step 4: Curdling the Soymilk

Next, transfer the soymilk to the smaller pot and bring it to a simmer, when tiny bubbles appear on the surface lower the heat slightly and cook it for 5 minutes stirring constantly. Don't let the milk get too hot or it will scorch and taste smokey. Meanwhile, dissolve the coagulant in 1/2 cup filtered water. After the soymilk is cooked remove from heat, let it sit for 2 minutes stirring occasionally. Now, using a spoon disperse 1/2 of the coagulant into the soymilk cover with a lid and let it sit for 3 minutes. Then, disperse the remaining half of the coagulant and mix it in slowly with the spoon, only putting the spoon into the top inch of the liquid. After 20 seconds curds should appear, cover the pot and wait 5 minutes, Remove the lid and give it a quick gentle stir, your curds should now be ready.

Step 5: Pressing the Tofu

In order to press the tofu, you will need to use a tofu press lined with 2 layers of cheesecloth. Then, using a ladle slowly ladle the tofu curds into the press until all the contents of the pot are in the press. Next, fold the cloth over the curds and place the top of the press on top. Add at least a pound of weight to the top of the press, you may need to think of something creative here, I used a stack of books stacked on a can. Wait for 15-20 minutes to remove the weight, now place the entire tofu press in cold water, either in a bowl or in a sink, for 5 minutes. Finally, your tofu is done and is ready to be eaten, if you plan on storing it for later use fill a container with cold water and keep it in a fridge.

Step 6: Conclusion - the Science

Tofu requires a long delicate process involving coagulation, curdling, temperature control, and emulsification. First, tofu is made with soymilk, made of soaked ground soybeans. The liquid is cooked so that it is digestible to humans, and the solid particles are removed. Once you have soymilk you must curdle it to make tofu. Curdling is the breaking of an emulsion, into curds and liquid. Curdling happens naturally with the right temperature and acids. In tofu, a coagulant is used, I used Nagari which is magnesium chloride which is a salt that curdles soymilk. In order for the milk to curdle, pH must drop making it more acidic and bitter as Nigari the coagulant used is the Japanese word for bitter. When the pH drops the proteins attract and clump, soybeans work for this because they are a legume and are a storage protein. Finally, the liquid drains out of the tofu press and the curds are pressed together until they bond into a block of tofu. And that is the process fo how tofu is made, I hope enjoyed it and good luck if you decide to try it.

Some references about the Science:

https://en.wikipedia.org/wiki/Curdling

http://www.ift.org/newsroom/news-releases/2016/feb...

https://en.wikipedia.org/wiki/Soybean

https://en.wikipedia.org/wiki/Emulsion

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