Takenoko

This is a follow up on my bamboo shoot (takenoko) post from January. Back then I was writing about my experiences of harvesting shoots of around 15 centimetres in length and a few centimetres in diameter. Now we’re talking about takenoko like the one pictured below. Compare the matchstick at the base of the shoot for scale.

There are a few meals in this Moso (Phyllostachys edulis) shoot. Before offering some suggestions as to what you might do with one of these giants I want add a couple of points to what I have previously written about the precooking of bamboo.

As I have said previously some bamboos contain cyanide which can be leached by precooking in water containing nuka (rice bran). Usually we save the water from washing brown rice and use this to precook the shoots. If you do not have any bran available a chilli pepper placed in the water is also said to remove the cyanide. Boil the bamboo shoots in water containing nuka or a chilli pepper for anywhere from 30 minutes to one hour.

Research conducted in Japan and reported in the Journal of Biochemistry, Vol. 44, Issue 10, has found that bamboo also contains homogentisic acid. This “growth factor” in the bamboo shoot is probably responsible for lending the bamboo a taste, or more properly, a sensation of the mouth, known in Japan as egomi (which Asako translates as googey). This is a similar sensation to that experienced when eating raw taro. The precooking of bamboo as described above removes the egomi from the shoots.

In Japan it is said that bamboo cooked and eaten immediately after harvesting contains very little egomi and even less if harvested in the morning. When both criteria are fulfilled often the bamboo will be eaten without any precooking at all. I do not know if the absence of egomi also indicates an absence of cyanide but the practice of eating unleached bamboo shoots, harvested in the morning and eaten soon after, is an ancient one so probably quite safe. If in doubt ask the bamboo. If still in doubt play it safe and precook the shoots. The cyanide is not present in quantities that will kill you but if, like us, it becomes a seasonal staple leaching the shoots is a good idea.

Pictured below is Tsuchiya-san our wonderful mentor in the finer points of harvesting takenoko and all things related to foraging and mountain living. To get the best shoots they should be harvested when only a few centimetres of the shoot is visible above the ground. The soil from one side of the shoot  is removed to the depth where the shoot joins the rhizome and the shoot is cut just above where the small roots emerge.

Takenoko steak

A great method of preparing fresh Moso (or other large) bamboo shoots that we were recently  introduced to is as a ‘steak.’ For this you use the large ends of the shoots. After precooking slice rounds of the shoots a few centimetres thick, score the flat surfaces to absorb flavour and pan fry in a little oil or butter. Alternatively, marinate the steaks (shoyu and ginger, maybe) and grill.

Bamboo is a fast growing prolific plant so if you have access to a stand there should be no shortage of shoots for eating. The shoots begin sprouting in spring and may continue for a month or more depending on the species and location. If you have access to a bamboo species like Moso in a single shoot there will likely be more than one meal. Given these factors bamboo is a good wild food to preserve. While fresh food is usually better than preserved food preserved food is better than no food. And preserved bamboo shoots are probably still better than the ‘fresh’ supermarket fare produced by industrial agriculture. And, of course, fermentation is more than just preservation…

Salted and dried bamboo shoots

Precook the shoots in water containing bran or a chilli pepper for a minimum of 30 minutes. Remove the tough outer skin and cut the tender centre into strips. Cook again in water. Remove surface moisture from the cooked strips of shoot and sprinkle with a generous amount of salt. Over the following three days dry the strips of shoot in the sun and massage them as regularly as you can. When the strips are thoroughly dry (about three days) store in an airtight container. For use simply remove any excess salt and rehydrate (soak in water for 15 minutes or more) before cooking.

Fermented bamboo shoots

After precooking the shoots cut them into large pieces and layer them in a vessel (ceramic, enamel or food grade plastic) salting them generously. Place a lid of a smaller diameter than the fermenting vessel on top of the salted bamboo shoots and place a weight on top. The salt will draw moisture out of the shoots assisted by the weight which will also keep the the shoots submerged in this liquid. The shoots will ferment in this liquid and be preserved. For use wash off any excess salt and cook (or eat as is).

These preservation methods should keep the shoots until the next takenoko season rolls around and probably a lot longer. We’ll let you know next year just how well these methods work.

Update: April, 2012

The preservation techniques described above were successful! Here we are, foraging bamboo shoots once again and we still have some of last years preserved shoots in fine condition. This year we will try reducing the amount of salt we used in the second technique. We will also be experimenting with another technique using a combination of salt and okara (a by-product of tofu making). I shall let you know how that one goes.

Also we have learnt, from the old mountain folk and by experience that when the eating the fresh shoots within a  day of harvesting, precooking is completely unnecessary.

 

Ferment III (Shoyu)

Shoyu is a fermented soybean product known to the English speaking world as soy sauce. Although, much of what is sold as soy sauce is not produced  by fermentation at all but is the product of a chemical process using soy extract, ethyl alcohol, sugar, salt, food colouring and preservatives. Tamari, originally a byproduct of the miso making process is now brewed,  using a similar process to traditional shoyu making but without the addition of wheat.

Soybeans are soaked, cooked (boiled or steamed) and left to cool. Cooling is facilitated by dividing cooked beans amongst a number of containers and regularly turning the beans to bring the hot ones below to the surface and fanning those on top. The amounts placed in each container are precisely measured to ensure the correct relative amounts of wheat can be added later.

Wheat is dry roasted. A slow even roasting is achieved by constant stirring over low heat. This can be done in batches and as long as the colour of each batch is similar an even roasting across batches has been achieved.

Roasted wheat, now cooled to room temperature, is mixed with koji (Aspergillus oryzae) and divided into equal amounts relative to the number of batches of soy beans cooling in the containers.

Wheat/koji is mixed through the soybeans. Then the remaining wheat is also added to the mix.

Wheat, koji and soybean mix is spread out onto bamboo trays covered with cotton inside a ‘plastic house’ (the greenhouses typically used by Japanese farmers). The next stage of the process, where the koji mycelium spreads through the bean and grain mix, requires a warm and humid environment, hence, the plastic house.

Magnolia leaves are placed directly on top of the bean/grain mix and these are covered with the edges of the cotton cloth.

Cotton sheets are placed over the trays and straw mats over the sheets.

In two to three days the koji will colonize the bean/grain mix and cover it with a fluffy, fragrant mold mycelium.

The bean/grain/mycelium mix is poured into a brine (sea salt and good quality water) and thoroughly mixed. From this point on the mixture (moromi) will need to be stirred every day for about one year after which it will be stirred every other day for another year. When stirring it is important to keep the sides of the barrel clean as it is here that contamination is likely to occur. The inside of the barrel above the level of the moromi should be carefully wiped down after each stirring.

The new batch in the rear, then a two year old batch and a one year old batch in the foreground. Between stirrings the barrels are covered with cloth.

Following is a description of what is occurring during the aging process.  It comes from the wonderful book Culinary Treasures of Japan: The Art of Making and Using Traditional Japanese Foods by Jan & John Belleme, 1992 (New York: Avery Publishing Group).

[E]nzymes from the koji and the naturally occurring yeasts and bacteria slowly breakdown the complex carbohydrates, proteins, and oils of the wheat and soybeans into sweet sugars, aromatic alcohol, and flavorful amino and fatty acids.

After about two years the moromi is placed in cotton sacks and pressed. The soy oil that rises to the top is skimmed off and you have the shoyu. It is left to settle, pasteurized under  low temperature and bottled.

Ferment II (Natto)

I’ve been a little quiet on the blog lately as we have been in the mountains in the Philippines without electricity or roads, let alone internet access. We hit a south east Asian natural farming jackpot in the mountains of Ifugao but you’ll have to wait a bit longer for the reports on that. In the meantime there are some posts that I began in Japan before leaving for the Philippines…

Natto is probably the most notorious of all the Japanese ferments. If you tell a Japanese person you like Japanese cuisine they will inevitably ask “but how about natto?” It seems that westerners particularly struggle to appreciate natto. I have introduced a few people to it and not one of them was willing to try it a second time (unless it was heavily disguised in miso soup). I believe its mostly the texture that people struggle with. The texture of natto is, well, slimey. The smell is also rather strong, comparable in intensity to a very mature blue cheese. Sound appealing? It is absolutely delicious, really.

Natto is made by fermenting soy beans. The nutritional value of many foods is increased with fermentation but it is particularly important with soy beans as the fermentation reduces the mineral binding effects of the phytic acids present in soy beans. Other forms of fermented soy beans include miso, shoyu (soy sauce) and  tempeh. Although natto is usually made with very small soy beans any soy beans can be used. In the step-by-step photographs of the natto making process below we are using large green soy beans.

After the fermentation process is complete natto is prepared for eating by whisking it up with chopsticks and, usually, adding a little mustard and shoyu. The whisking creates a kind of goo resembling melted cheese that sticks to the beans and makes them potentially very messy to eat. It is usually eaten with rice and, just in case the strong smell, strange flavour and slimey texture aren’t enough, it is often eaten for breakfast, when our stomachs are at their most vulnerable!

Natto process, from top to bottom:

1. Rice straw contains the bactria Bacillus subtilis. It is this bacteria that is used to ferment the soy beans in making natto. The rice straw is cut to size to fit in the plastic containers we are using. Traditionally the natto is made in a rice straw ‘package’.

2. The rice straw is pasteurized (heated to about 65 degrees centigrade). Bacillus subtilis can withstand relatively high temperatures so pasteurizing the straw kills off other bacteria and favours the Bacillus subtilis.

3. Cool the pasteurized rice straw.

4. Place half the rice straw on the bottom of a container.

5. Place cooked soy beans on the rice straw. The soy beans should be soaked overnight before cooking. Because Bacillus subtilis can withstand high temperatures it is not necessary to cool the cooked beans although it is probably best to let the cooked beans sit for 10 minutes or so after cooking is finished.

6. Place more of the rice straw on top of the beans.

7. Put a lid on the container and place in an insulated box with a hot water bottle. Let sit over night and the natto should be ready just in time for breakfast.

8. In my eagerness to taste the natto we had made I forgot to take a photograph of it! This photo was found on the web and shows natto made from the smaller brown soy beans that are typically used in commercial natto production.

Coming Soon: Ferment III (Shoyu)