Fermented Soybean Cake

…a contribution from Java to the world…

You are probably wondering why on the world did I include ‘tempe’ or ‘tempeh’ in this website? As a matter of fact, this is my favorite food overall. Let me give you a little bit explanation for those of you who doesn’t know the meaning of tempeh or tempeh. Tempe, by the nutritionist, is often called as ‘meat from agricultural sector.’ What it means is that tempeh is rich of protein just like meat. Tempe is made from fermented soybeans which fermentation is resulted from Rhizopus bacteria. The fermentation of this is set under a certain temperature. Tempe has a softer texture than soybeans because the enzymes resulted from the fermentation are causing the modification of the protein, fat, and carbohydrate structures. The enzymes produced by the fermentation are lipase, protease, and amylase. In your stomach, these enzymes can help you to digest food more easily.

Due to its richness in protein, tempeh has been known as a meat substitute in the Asian market. Although it was originally found in Java, Indonesia, but now the people from Singapore, Japan, and all other nations have considered tempeh as a healthier alternative source of protein instead of meat. In Japan, some people are getting crazy on this as they cook tempeh in so many ways. Tempe tempura, tempeh steak, and tempe burger are some of the ‘weird’ ideas to describe how they serve tempe in some other ways. This trend in Japan was ignited by awareness to the epidemic of bacteria E coli in the meat in 1996, which had killed thousands of children and adults.  In the Encyclopaedia Van Nederlandsch Indie (1922), tempeh was described as a ‘cake’ made from soybeans, and had been known as volk’s voedsel (traditional people’s food). Most of the people from Indonesia consider tempeh as a cheap food, and some of them hesitate to consume tempeh because they think that it’s only for poor people. They are wrong! Some of the researchers and scientists from all around the world have been putting interest on this food. In Indonesia, there has been established Indonesian Tempe Foundation to learn more about tempeh and how to make better development of this product.

So, if you are looking for a healthy food for your diet, consider tempeh hehehehe. Do I sound too promoting? Maybe I do J

Now, how do we make that? Follow me…(adopted from a trustworthy source)

Although you can make Tempeh from many different types of pulses and grains I suggest that you start off with a well tried-and-tested variety first in order to familiarize yourself with the method and also to gain experience of how the fungus grows, matures and tastes with your particular set of conditions. You can experiment later when you get the method perfected!

12oz soybeans
1 level teaspoonful Tempeh starter inoculums
¼ cup cider vinegar (c. 60ml or 4tbsp)
Tetra Brik* (or other incubating container)
Warm place to incubate - steady 30-32degrees Celsius

Be careful not to contaminate your starter and after removing what you need always expel as much air as possible from the bag by rolling it up from the bottom, sealing carefully and storing it in the fridge. Never introduce moisture into the bag by leaving it open in a steamy atmosphere or by using a wet spoon; if you look after your starter it will give you over 10 kilos of finished Tempeh, remember!

The vinegar is added to the soaking water in order to inhibit unwanted bacterial growth - don't forget to add it.


The very best (and free) incubating container to use is a one-liter size soymilk box (UHT udder milks, fruit juices and many other liquids also come in them, they are widely used), which is called a Tetra Brik. If you open it carefully by cutting right across the top as close to the seal as possible in the first instance, you will then be able to wash it thoroughly with hot water after use and dry it ready for your first batch of Tempeh. All that remains is to prick a grid of air holes all over it, at a spacing of about ½", for ventilation. Another joy of the Tetra Brik is that the finished Tempeh can easily be stored in the fridge or put straight into the freezer in it after incubation - just pop the whole thing into a dated freezer bag and freeze! The quantity of beans used in this recipe is designed around the use of a one-liter size Tetra Brik, but if you want to make a smaller quantity or are experimenting with different pulses and grains you could use the ½litre (or smaller, i.e. Ribena drink) size, adjusting the quantities accordingly. The finished one-liter soy 'Brik' weighs 850g.

A steady 30 - 32 degrees Celsius (86 - 89 degrees Fahrenheit) is required for good growth, although a slightly lower temperature will be tolerated but this will slow up Rhizopus, increasing the risk of bacterial contamination and drying out of the beans. Never allow the culture to overheat too much or Rhizopus will be killed. The ideal temperature may be achieved either by the use of a (very) warm airing cupboard (use a thermometer to check) or an incubation cupboard set aside for the purpose. The latter need only be a small section of your kitchen cupboards containing either a wine heating pad, yogurt maker, pain-relief heating pad or low wattage light bulb - experimentation with insulation and ventilation will be required to achieve the correct temperature. When incubating your Briks, make sure there is adequate airflow around them to stop any localized overheating, i.e. raise them up from the heat source on a wire cake cooling rack or equivalent.


It is usually advised that soybeans be dehulled before inoculation, but after producing Tempeh on both dehulled and entire beans I can see no benefits to be gained by including this time-consuming step in the process. If you find dehulled soybeans easier to digest and would therefore like to include it, however, bring the beans up to boiling point in the vinegar-ed water from cold and then turn off the heat. Allow to cool to room temperature, then rub the beans between your hands to loosen and remove the hulls which will float to the surface and can then be skimmed off. Continue with the method as before using fresh water but reduce the cooking time slightly to take account of the extra cooking already received.

Soak the beans overnight in 2 pints of (filtered if possible) water to which you have added 4 tbsp vinegar. Drain and cook them in a fresh quantity of water, either in a pressure cooker or on top of the stove until very tender but not falling apart. Drain well until there is no free water and allow cooling to about blood heat before adding the starter. Sprinkle evenly and then stir well to disperse the starter but take care not to break up the beans, as there must be plenty of air spaces between them during incubation. Pour them into the previously pricked Tetra Brik and seal the top with wide masking or parcel tape. Re-prick the holes you have covered. Place in the incubation area, turning occasionally during the growth period to ensure even warmth. After 24 hours check the progress by carefully un-taping the end of the box - when ready the beans will be amalgamated into a solid white cake and have a pleasantly 'mushroomy' smell (any unpleasant, acrid smells or soft, liquefied areas could indicate infection - if in doubt always discard and start again; did you forget to add the vinegar to the soaking water?). There may be areas of gray or black appearing adjacent to the air holes, this is purely indicating that Rhizopus is mature and is producing reproductive spores; it is in no way detrimental to the flavor or condition of the Tempeh. If you have judged that there is not yet adequate growth then re-tape and allow a few more hours incubation; check regularly from now on, however, as the speed of growth seems to increase tremendously in the later stages of development, possibly due to additional heat produced by the fungus itself during the growth process. When the Tempeh has reached the desired state of maturity (you will soon get to know how you like it) you may store it in the fridge for up to a week or in the freezer for several months.