Introduction

You may have already heard about tempeh and its numerous health benefits. A fermented product made from soybeans, tempeh is highly appreciated by vegetarians and vegans seeking a varied and tasty protein source. Its slightly nutty flavor and firm texture make it a versatile ingredient for a multitude of dishes, from quick sandwiches to slow-cooked curries. In this article, we will explore the ins and outs of making homemade tempeh. Whether you are already a fan of plant-based cooking or simply want to enrich your diet, you will find all the necessary steps here to prepare your first batch of tempeh and tips to showcase it in your daily recipes.

Tempeh is a staple food in some Asian regions, particularly in Indonesia where it originated. Despite its apparent simplicity, this fermented preparation requires a method and certain know-how, which you can largely acquire with a bit of practice. You will see that the experience of watching soybeans transform into a rich and tender block is rewarding, and it is especially a source of great pride when you manage to make it yourself. So, ready to discover all the secrets of homemade tempeh?

What is Tempeh?

Tempeh is a food obtained by fermenting soybeans or other legumes (chickpeas, split peas, etc.) with a fungus of the Rhizopus genus. It has a dense and firm texture, which differentiates it from tofu, which is often softer and does not undergo similar fermentation. Originating from Indonesia, tempeh has gradually made its way into global vegetarian cuisine for its taste qualities, protein richness, and nutrients.

Here are some key characteristics of tempeh:

• It is rich in complete proteins and essential amino acids.
• It contains fiber, vitamins, and minerals such as calcium and iron.
• It has a firm texture, sometimes crunchy if pan-fried.
• Its taste is slightly reminiscent of mushrooms and nuts, with a hint of earthy flavor.

In addition to its nutritional qualities, homemade tempeh offers another advantage: you have complete control over the manufacturing process. This ensures the quality of the ingredients and the absence of undesirable additives. You can also vary the legumes (soy, lentils, beans, chickpeas) to create personalized tempeh. The taste will then be slightly different depending on the raw material.

The Nutritional Benefits of Tempeh

Tempeh is particularly popular in vegetarian diets primarily due to its high protein content. For people who do not consume meat or fish, finding alternative protein sources is a major challenge. Tempeh stands out in this area, as it provides high-quality plant proteins containing almost all essential amino acids.

Moreover, fermentation makes the nutrients in legumes easier to assimilate. The microorganisms involved in fermentation partially break down fibers and complex carbohydrates, making the final product more digestible. Additionally, fermentation promotes the development of probiotics, microorganisms that contribute to gut health and enhance digestion.

Tempeh is also an interesting source of vitamins, particularly B vitamins. Furthermore, its mineral content (iron, calcium, manganese, magnesium) makes it an additional asset to complement a vegetarian or vegan diet, often criticized for potential deficiency risks. Integrating tempeh into your dietary routine is therefore an excellent way to diversify your intake of key nutrients while enjoying a unique flavor.

The Different Ingredients for Making Tempeh

To make homemade tempeh, you will primarily need soybeans and a starter culture, often called a “starter” or “inoculum,” which contains the spores of the fungus Rhizopus oligosporus or Rhizopus oryzae. These spores enable the fermentation and transformation of legumes into tempeh.

Here is the basic list of ingredients:

1. Soybeans: Generally, non-GMO, whole, and well-dried yellow soybeans are preferred. Some opt for other varieties of legumes (chickpeas, lentils) or a mix.
2. Tempeh starter: It often comes in the form of a white powder containing the spores necessary for fermentation. You can find it online or in some specialty stores.
3. Vinegar (optional but common): A bit of vinegar is sometimes added during preparation to acidify the mixture, facilitating the start of fermentation by creating a favorable environment for the fungus culture.

It is essential to obtain a high-quality starter to ensure optimal results. Also, ensure the freshness of your beans: too old or poorly stored beans may have moisture or rancidity levels that prevent proper fermentation development.

Necessary Equipment

The equipment required to prepare tempeh is not complicated, but it is important to master temperature control and hygiene for successful fermentation. Here is the basic equipment:

• A large container for soaking and cooking your soybeans.
• A colander to drain and rinse the beans.
• A kitchen thermometer: Maintaining a stable temperature is crucial (ideally around 30°C). A thermometer will help you check the ambient temperature or that of an incubator.
• A perforated freezer bag or perforated container: Tempeh ferments in an environment where air can circulate. Some also use trays covered with plastic wrap with holes.
• An incubator (optional): If you live in a cold climate, a kitchen oven or an incubator can help stabilize the fermentation temperature.
• A wooden spoon to mix the beans.
• Tea towels to retain heat around the container if you do not have an incubator.

You will find that many homemade tempeh enthusiasts come up with ingenious solutions to maintain the ideal temperature: a polystyrene box with a low-power bulb, an oven turned off with the light on, or even a simple radiator. The important thing is to maintain a relatively stable temperature for about 24 to 48 hours.

The Step-by-Step Tempeh-Making Process

1. Soaking and Washing the Beans

Start by soaking your soybeans in a large volume of water for 8 to 12 hours, preferably overnight. Soaking allows the beans to hydrate and soften. Monitor the water volume to ensure they are always well submerged.

After this step, drain and rinse your beans. It is sometimes recommended to remove the soybean hulls. This improves the quality of the tempeh by allowing the fungus to penetrate more easily. To do this, gently break the soaked beans between your fingers or with a whisk, then rinse several times in fresh water. The hulls will float and can be removed by hand or by pouring off the rinse water.

2. Pre-Cooking the Beans

Once your beans are washed and mostly free of hulls (this is a partial task, not all hulls need to be removed 100%), you will cook them. Place the beans in a saucepan, cover them with water, and bring to a boil. Cook for about 30 minutes, until they are slightly tender but still a bit firm. The goal is not to cook them completely as for a traditional dish, but just to pre-cook them to facilitate fermentation.

When the pre-cooking is finished, carefully drain the beans. They should be as dry as possible before the next step. Excess moisture can prevent the fungus from developing properly and cause undesirable mold.

3. Acidification (Optional) and Inoculation

At this stage, some people add a tablespoon of vinegar for every 500 g of cooked soybeans. This light acidification creates an environment favorable to the development of the Rhizopus fungus and helps prevent the growth of other undesirable microorganisms. Mix the vinegar well with the beans.

Then, let the beans cool to a maximum of 35°C (as beyond that, they may kill the fungus spores). When the temperature has dropped, add the starter according to the manufacturer’s recommendations. Generally, about a teaspoon of starter is needed for 500 g of cooked soybeans. Mix gently to evenly coat all the beans.

4. Placing in a Perforated Bag or Container

Transfer the mixture into a freezer bag or a thin plastic container, previously perforated with multiple small holes (spaced a few centimeters apart). Spread the beans to form a layer about 2 to 3 cm thick. Seal the bag or container well to maintain humidity and limit external contamination while allowing the fungus to breathe.

Next, place the bag in a warm area, around 30°C, and let time do its work. The first 12 hours are crucial. You can check it from time to time to ensure the temperature remains stable and that the bag does not show excessive condensation.

5. Fermentation

Fermentation generally lasts 24 to 48 hours. Gradually, a white film will form around the beans. In addition to this film, you will feel a slight warmth emanating from the bag. If the temperature rises too high (above 37°C), the spores may be damaged. In this case, you can slightly aerate the bag or move it to a cooler environment.

After 24 hours, check the progress. If you already see a well-formed “cake,” you can stop the fermentation. Sometimes, you need to wait up to 48 hours to obtain a firm block. A pleasant mushroom smell will emerge. If you notice a pink, gray, or black color spreading too much, it is generally a bad sign: the batch may be contaminated, and you will need to discard it.

Tips for Successful Tempeh

• Maintain good hygiene: Thoroughly clean all equipment and the workspace to avoid contamination. Properly dry your beans before adding the starter.
• Respect the temperature: The fungus develops ideally between 28°C and 32°C. Temperature fluctuations slow down the process or promote harmful bacteria.
• Monitor humidity: If the mixture is too moist, the mold will not develop properly. If it is too dry, the tempeh may not form.
• Be patient: It sometimes takes time and experimentation to achieve perfect tempeh. Each home has its own microclimate.

Preserving and Storing Homemade Tempeh

Once fermentation is complete, you obtain a more or less compact block of tempeh, often creamy white. You can either use it immediately in your recipes or store it. Tempeh keeps well in the refrigerator for about a week. It is also possible to freeze it to keep it for several months without significantly altering its taste quality.

Before freezing, you can cut it into slices or cubes to facilitate its future use. Place them in an airtight freezer bag or container. When you want to cook it, simply thaw the desired amount and incorporate it into your recipe.

Ideas for Cooking Tempeh

Tempeh is particularly versatile in cooking. It is often used:

• Marinated and grilled: Cut the tempeh into thin slices, let it marinate in a mixture of soy sauce, sesame oil, spices, or lemon juice, then grill it in a pan. Ideal for topping a sandwich or accompanying cooked vegetables.
• Crumbled: It can easily replace ground meat in dishes like bolognese, chili, or even in vegetarian meatballs.
• Sautéed cubes: In a wok with vegetables, ginger, garlic, a few cashews, and an Asian sauce. A quick and nutritious dish.
• Stewed: It can also withstand long cooking in vegetable curries, tomato sauces, or coconut milk sauces.

Classic Marinades for Tempeh

1. Soy-Ginger Marinade: Soy sauce, freshly grated ginger, garlic, a few drops of sesame oil. Add a bit of sugar for a caramelized touch.
2. Sweet and Savory Marinade: Maple syrup, soy sauce, garlic powder, mild chili.
3. Coconut-Lemongrass Marinade: Coconut milk, minced lemongrass, curry, salt, pepper.
4. Spicy Marinade: Mix of chili, smoked paprika, cumin, concentrated tomato sauce.

You will find that tempeh has the ability to absorb multiple flavors, allowing it to adapt to different types of cuisine around the world.

Some Tips for Going Further

• Vary the legumes: You can make tempeh with chickpeas, red beans, coral lentils. The process does not change much, although cooking time varies depending on the legume.
• Add grains: Some mix soy and cooked rice to add extra texture and a different taste.
• Play with spices: Why not mix a bit of chili or turmeric with the cooked beans before inoculation? You will get a slightly colored and flavored tempeh.
• Share your experiences: Participating in fermentation or plant-based cooking discussion groups can help you refine your technique and discover other recipe ideas.

The Ecological and Ethical Benefits of Tempeh

Tempeh is a highly appreciated substitute for animal proteins. By favoring this type of food in your diet, you contribute to reducing the carbon footprint generally associated with meat production. Legumes require less water and land resources compared to intensive farming. In a conscious consumption approach, betting on tempeh is therefore part of a broader perspective of environmental respect.

On the ethical front, tempeh also helps limit animal suffering by reducing dependence on meat while ensuring complete nutritional intake. It easily integrates into your everyday cooking and can be prepared in multiple ways for every type of dish.

Potential Health Concerns

Like any fermented product, tempeh requires basic hygiene precautions to avoid contamination. Ensure the freshness of your beans and respect the fermentation temperatures. If you notice unusual odors (unpleasant moldy smell, pronounced sour smell) or alarming colorations, it is safer not to consume the product. Apart from that, tempeh is generally well tolerated, even by people who have difficulty digesting legumes. Fermentation helps make the beans more digestible.

Regarding fermentation, some people sometimes worry about the presence of mold. In the case of tempeh, these molds are controlled and beneficial. However, they should not present strange colors. “Normal” tempeh is creamy white, possibly punctuated by a few black spots on the surface, which is common and generally a sign of good fermentation.

Conclusion

Tempeh is a valuable food in a vegetarian or simply diversified diet. Its nutritional properties, protein richness, and characteristic flavor make it a choice ingredient for all kinds of recipes. Of course, like any fermented product, its artisanal production requires rigor and patience. It sometimes takes a few tries to find the perfect method for your environment.

But rest assured: once the main steps are mastered (soaking, pre-cooking, inoculation, and temperature control), you can make your homemade tempeh without difficulty and enjoy a natural product without additives. Feel free to test different legumes, vary seasonings, and explore various culinary techniques. Tempeh is a particularly interesting gustatory playground, bringing benefits and originality to the table.

Making your own tempeh is as rewarding as it is economical. You will discover the pleasure of tasting a food that you have crafted from A to Z, from seed to plate. You will thus benefit from unparalleled freshness and complete control over the ingredients. So why not take the plunge today? Embark on this culinary adventure and treat yourself to the best of plant fermentation. Enjoy your tempeh and, above all, bon appétit!