Anything I’m Fermenting

April 30, 2008

Salty Language!

Filed under: Brining,Soy Sauce — iwouldntlivethere @ 2:14 pm
Tags: , ,

Inigo, from Umami Madrid sent me a truly fascinating email a few days ago, explaining that he had contacted Kikkoman Europe about how much salt to use. With his permission I have posted the exchage, starting with Kikkoman’s initial response to how much salt to use:

Dear Mr. Inigo Aguirre,

First of all, we thank you for your inquiry and your interest in making soy sauce by yourself for educational purposes.

As per your inquiry, I’m happy to reply although this may not be enough information to you.

It all depends on what kind of soy sauce (salty, light, etc.) you intend to make, but we suggest that you use 30 g of salt per 100 ml of water used.

I hope you will find a way to make it successfully.

Best regards,

Takehito Kubo

Kikkoman Trading Europe GmbH

So Inigo replies:

Dear Takehito,

Thanks very much for your info and kindest help. I have been using 25 g of salt per 100 g of water, so I think it will be fine.

One…actually two more questions:

What is the minimum amount of satl that could be used (e.g. for light soy sauce)?

Do you use wheat for the soy sauce or is flour just as good? I understand that Japanese soy sauce is done with whole toasted wheat, whereas Chinese soy sauce is done with wheat. Is this so?

In case you’re interested please click on my blog to see how I’m doing it (sorry, it is in Spanish).

Thank you very much. Best regards,


And so Kikkoman replies again:

Dear Mr. Inigo Aguirre,

Thank you again for your inquiry.

For your information, it is recommended that you use at least 15 to 16% salt, otherwise the moromi mash could decay.

Furthermore, we use whole wheat as an ingredient to be roasted.

For general information, please find attached the process of making naturally brewed soy sauce.

I hope this information can be of help.

Best regards,

Takehito Kubo

Kikkoman Trading Europe GmbH

Tempeh Tasting, Part 2

Filed under: Tasting,Tempeh — iwouldntlivethere @ 2:05 pm
Tags: , , ,

As J.Back points out, the true test of how the tempeh tastes is how my wife feels about it, as she is really the tempeh fan around here. Once I saw J.Back’s comment, I immediately asked what Jul thought of the tempeh. She said: “Good!…I just had some tempeh at Juice-for-Life and it tasted just like that.”

So, there you go. Using store-bought tempeh as a starter really does work, and tastes like store-bought tempeh.

April 25, 2008

Tempeh Tasting

Filed under: Tasting,Tempeh — iwouldntlivethere @ 3:59 pm
Tags: , , ,

Just a quick comment on how the tempeh tastes. I fried up strips of tempeh in a bit of oil and butter, and seasoned with a bit of salt.

It tasted like…well, fried tempeh! Kind of bitter, kind of mushroomy, kind of beany. It was good.

The real test will probably be if my wife, a true tempeh lover, will enjoy it raw, as she eats store-bought tempeh this way. My thoughts on raw tempeh? Bleagh!

April 24, 2008

Tempeh Part 2: Fermentation

Filed under: Tempeh — iwouldntlivethere @ 2:47 pm
Tags: , , ,

Step 12: Let ferment at 30 degrees for 36-48 hours.

I believe that my fermentation temperature for the first 12 hours or so was around 28. It subsequently started rising, and I had to remove the lights, one at a time. I eventually clued in to the fact that the tempeh packages were generating a lot of heat – so much so that I had to remove some of the packages from the cooler for a while and place in a drafty window to cool down. They remained quite warm to the touch for the last 12 hours of fermentation *.

Step 13: Cut in half while in perforated bags. Remove the halves and wrap in cling wrap. Consume, freeze and/or refrigerate as required.


Day 1, afternoon – grind soy beans to remove husks and begin soak

Day 2, late evening – cook soy beans, dry, inoculate, fill perforated bags (around midnight)

Day 3, morning – checked temperature – around 28, added a few lights into cooler. Noticeable mushroom aroma in cooler.

Day 3, midday – checked temperature: mid to high 30s! Progressively removed lights from cooler, until none remained. Fungal strands visually apparent.

Day 3, afternoon – temperature again has risen to high 30s, remove bags from cooler and set in window to cool off.

Day 3, afternoon – return bags to cooler after 30 minutes, but leave cooler open to dissipate heat.

Day 3, evening – bags still warm to touch, visually beginning to be covered by white fungal growth, but many individual beans still visible.

Day 4, morning – bags warm to touch, most covered completely by fungal growth; black spore areas near perforations in bags. Removed from perforated bags, wrapped in cling wrap, placed in freezer. During handling some white fungal areas crushed and oxidized somewhat – beans again visible occasionally (see photos).

* One of the bags (see photos) did not have a nice uniform white fungal coating by the end. It did have good coverage around the edges of the bag, but not in the centre. I believe this may be because it possibly overheated during fermentation. My reasoning is that I am fairly sure that the inoculum was evenly distributed throughout the soy beans, and even if it hadn’t been, it would not have been missing from such a large, symmetrical area in the centre of one bag. Further, the fact that the mold did take successfully around the edges of the bag, where it would presumably be cooler than in the centre, also point to heat damage. Some of the patties were verging on hot to the touch during the fermentation.

It can be seen on the area that has not been covered by fungal growth that there are nevertheless many fungal strands crisscrossing the soy beans. This would also indicate that it was not a lack of inoculum that caused this.

Another culprit may be anaerobic conditions, but I do not believe that this would have manifested itself in such a pattern.

The question remains, why only on one bag? I haven’t weighed the bags, but this bag appears to be somewhat thicker and heavier, meaning it would generate proportionately more heat than bags with fewer soy beans. As well, I accidentally left one of the bags in the cooler, while the others were out in the window. This may have been the one that stayed in the cooler.

As a result, I have left this one bag in the cooler in the hope that the fungus will be able to recolonize the middle area. As the fermentation has only proceeded for about 34 hours, I believe that I can safely let the bag continue to ferment for at least 12 hours if necessary.

Tempeh Part 1: Soak, Cook, and Innoculate

Filed under: Tempeh — iwouldntlivethere @ 3:24 am
Tags: , ,

Step 1: Buy package of unpasteurized tempeh (found at Noah’s at Bloor and Spadina) and dry soy beans

Step 2: Grind soy beans in grain mill, at a very loose setting, to remove seed husk.

Step 3: Soak split, de-husked soy beans overnight

Step 4. Boil soy beans for about 30 minutes until softened

Step 5. Puree store-bought tempeh to create starter

Step 6. Strain boiled soy beans, shake out excess water, then lay out on towel and roll up to absorb any remaining water (every tempeh making guide has stressed this, see photos)

Step 7. Punch holes in zip-lock bags to allow oxygen to enter fermenting tempeh (I used a fine-tipped chopstick)

Step 8: Drizzle about 3 tablespoons of white vinegar on dried soy beans and mix well

Step 9: Mix boiled, dried soy beans with pureed tempeh. Mix well, making sure to break apart any clumps and ensuring that most pieces of soy bean had touched fragment of tempeh – to evenly innoculate

Step 10: Partially fill bags with tempeh/soy bean mixture. Press flat.

Step 11: Place filled bags into a cooler with a string of non-LED, miniature Christmas lights to maintain a temperature of around 30 degrees. Monitor temperature and remove lights as necessary to prevent over-heating (I think the ambient temperature was around 22, and I needed only around 4 lights in the cooler to maintain temperature).

April 22, 2008

Soy Sauce Part 3: Brining

Filed under: Soy Sauce — iwouldntlivethere @ 3:36 pm
Tags: , , ,

Step 9: Make brine solution. I ended up using a solution of 3 liters (or 3000 g) of water with 200 grams of salt. This is a 6.7% salt solution*.

Step 10: Ferment soy chunks in brine for a few weeks. My fermentation took place in a food-grade plastic bucket, covered loosely by cling wrap held in place with an elastic. It is placed in a large west-facing window in a room that heats up considerably in the afternoon**. I try to stir it once a day. I have noticed that the soy chunks stayed whole for a few days, before breaking down, although a few are still fairly whole. Initially the fermentation produced some bubbles, but that stopped after the first few days.

The fermentation does not have a strong smell as it is partially covered. Even when open, during the first week it had only a mild, fungal smell like freshly cut button mushrooms. After about a week the fermentation formed a pellicle – a bacterial/fungal mat covering the surface (see photos). As well, when the cling wrap covering is removed a somewhat stronger smell is apparent. However, the smell is not unpleasant, being quite yeasty, somewhat like beer fermentation, but more earthy (and obviously without hop aroma). Directly smelling the spoon used to stir the brine brings out again the fungal smells, but also a sour smell – probably lactic acid bacteria. Haven’t had the courage to taste it yet though!

* In this case ‘canucklehead‘ was a bit vague about the amount and strength of the brine. At first he suggests: “the fermented disks are soaked in a brine that contains 8 oz of salt” and later “start out with 4lbs of water with 4 oz of salt”. That works out to about a 6% salt solution, by weight. I checked the label of my ‘naturally brewed’ Kikkoman soy sauce, and the salt concentration is about 7% by weight. So that seemed to be a pretty close match.

I also came across (have lost the link) a Google book about food safety in food processing . They talk about brining and different strengths and uses of brining. They said the minimum safe concentration of salt is about 10%; however later when discussing fermentation (of sauerkraut or pickles) they suggest concentrations of around 8% in order to allow the lactobacillus to thrive. This makes sense, as above 10% the fermenting organisms themselves are inhibited.

Canucklehead’s 4 lbs of water is about 2 liters, so I may be making a more dilute soy sauce (i.e. more brine per soy), but he says initially that his brine contains 8 oz of salt, which means that he would have needed about 4 liters of water. In that case, my soy sauce would be more concentrated. As with brine strength, I have gone with a middle estimate.

Subsequently on the eGullet forum on which canucklehead has been posting, “inigoaguirre” posted a link to his blog (unfortunately for me, in Spanish) showing some pictures of his soy experiment. As well, he states that:

the brine should have around 25% salt (you should heat at least a part of the water in order to dissolve the salt otherwise you would end up with all the crystals in the bottom). Kikkoman uses for their classic soyzu 23% salt; you can also find soy sauce with low salt content, but the proportion should still be quite high”

Not sure about this – on one hand, it looks like his soy sauce fermentation has succeeded (see his blog). Salt concentrations of 25% or so would definitely need boiling water to create the solution. However this concentration is well above canucklehead’s suggestion, and does not correspond to what my Kikkoman soy sauce (not low-sodium) bottle’s label states (you can calculate it yourself: per 15 mL serving there is 920 g sodium). What’s going on?

One idea is that Inigo and I are calculating salt concentrations differently (I’m fairly seat-of-my-pants on this). Although his statement about heating the water suggests that his salt concentration is indeed higher than mine (which just required a bit of stirring to dissolve). Also, the Kikkoman label deals with sodium, not salt…so the chloride part of salt is not included. As I am too lazy to revisit my high-school chemistry on molar weights, I have not bothered to figure out how much this affects my salt concentration calculations. My guess is not enough to bring my figure up to 25% though – chlorine is much smaller than sodium, and even if they were the same size, it would double the salt concentration to around 14%, still far from 25%.

Another hypothesis is that Inigo’s fermentation may not be via active bacterial/yeast culture. Rather, leftover enzymes (from the molds on the soy patties) that are not denatured in the saline environment may be causing the soy sauce to ferment. As well, if these enzymes produce acids, or if the mold produced acids in the soy patties, and Inigo has placed his fermentation jar out in the hot Spanish sun, he may be creating low-level acid hydrolysis reactions. Acid hydrolysis is how a lot of cheap ‘soy sauce’ is produced – although under industrial conditions using heavy duty acids and high heat and pressure. This is pure conjecture!!!

** Canucklehead says:

Large containers sitting out in the sun (under plexiglass). I actually don’t understand why this needs to be done – but my uncle says that my grandmother would always let the sun cook out the water – sometimes for a whole month. Perhaps this was a way to remove impurities – when tap water was not so safe”

I don’t really agree with his theory – based on what I have read about the manufacture of soy sauce, it is more likely that this practice was to warm up the fermentation, speeding it up, and creating more intense flavours. In Japan, before WW2, soy sauce was usually brewed during spring or fall specifically to achieve a mellower flavour from cool temperature fermentation. This also corresponds to beer brewing – fermenting at higher temperatures creates a lot of extra flavours that are not usually desirable in beer.

As this soy sauce recipe appears to be of Chinese origin, I have put my fermentation bucket in a warm spot in a very sunny west facing window.

Canucklehead goes on to discuss something I have read fairly frequently elsewhere on soy sauce fermentation:

I mentioned that they looked awfully pale to make a dark soy sauce – but he said that the brew will darken as it sits in the sun. “Just like how people get tanned.” Huh? I don’t understand how it can get darker – the brine is very salty – so I assumed that there would be no further fungal growth – but how can it get darker?”

Based on what I have read of Japanese soy sauce manufacture they ferment and age their soy sauce in the dark, and their soy sauce turns quite dark without exposure to the sun. The soy sauce is made dark likely by using roasted wheat, by pigments from the molds, by reactions during fermentation, and perhaps due to oxidation (like how an apple’s flesh turns brown with exposure to the air). On the other hand, it really may be that the microorganisms ‘get tanned’ somewhat to protect themselves from UV radiation by producing some sort of pigments.

And just to clarify (“I assumed that there would be no further fungal growth“), there is definitely active growth by microorganisms in the brine – from what I have read this includes most of the organisms involved in brewing beer: yeasts (kloeckera, saccharomyces, brettanomyces and probably others), and bacteria (enterobacteria, pediococcus, lactobacillus, maybe the clostridium and probably others). I doubt the molds themselves are able to grow so canucklehead is partly right – they are likely inhibited by the anaerobic and saline environment of the brine. So I believe their primary purpose is to pre-digest the soy beans and provide extra enzymes for the fermentation. They are themselves probably consumed by the fermentation yeasts and bacteria.

Soy Sauce Part 2: Dry Soy Chunks

Filed under: Soy Sauce — iwouldntlivethere @ 2:10 pm
Tags: , , ,

Step 7: Lay out moldy soy patties and allow to dry (outside in the sun if possible)

Step 8: When the outside of the soy patties had dried, I broke them into quarters to speed the drying process.

Here are what my dry soy ‘chunks’ looked like.

Note that they have turned a dark brown colour.

However a few of the thicker pieces were not quite as dark in the middle (see the close-up):

April 21, 2008

Soy Sauce Part 1: Moldy Soy Patties

Filed under: Soy Sauce — iwouldntlivethere @ 10:30 pm
Tags: , , , ,

As per the instructions given by ‘canucklehead’ on eGullet’s forum, here is how I have made soy sauce at home:

Step 1: Soak 500 g dry soy beans overnight

Step 2: Boil soy beans until soft and crumbly

Step 3: Coarsley chop in food processor and mix with 300 g (whole wheat in my case) flour. I used whole wheat as it is less processed than white flour, meaning it likely has a greater diversity of microorganisms surviving in it.

Step 4: Form bean/flour mix into a loaf and slice into patties about 1 cm in thickness

Step 5: Lay out ‘soy patties’, cover with damp paper towels, and loosely wrap in cling wrap.

Step 6: Monitor patties, dampening towels as needed. Let sit for 5 – 10 days, until well covered by mold. In my case, the patties did not appear to be doing much for several days, but began to smell like my salt-risen bread starter (Clostridium bacteria). Then over two days the patties became completely covered in various molds:

Blog at