Anything I’m Fermenting

November 6, 2008

Louisiana Hot Sauce Update

After a couple weeks souring with lactobacillus, I concluded that not much new was happening with the hot peppers, so I pureed them and added some white vinegar to knock off the fermentation. Not very precise, I know, but I can’t remember exactly how much vinegar – I just added a bit at a time until the sauce had a consistency I liked. (more…)

June 9, 2008

Kimchi

Sorry about the dearth of posts recently – we just moved and this included a lot of repainting and other work on the new apartment. Now we’ve settled in a bit, and my itch to ferment has returned.

We now live not far from Korea-town or Little Korea, or whatever they call it. This means that one of the nearest supermarkets is Korean owned and managed, for Korean customers. They obviously sell all you need to make kimchi – nice big nappa cabbage, giant radish, fish sauce, shrimp paste, chili powder, etc.

Here’s my recipe:

1 (medium large) head nappa cabbage

1 (medium) ‘Korean’ radish

1 bunch scallions

4 cloves garlic

1 tsp ginger

sea salt

chili powder

1 tbsp sugar

1.5 tbsp fish sauce

Directions:

1. Quarter cabbage, core, cut to 3 cm lenghts

2. Wash cabbage pieces, drain well

3. Take a good handful of cabbage pieces, place in plastic bag, sprinkle 1 heaping tbsp salt over cabbage, and mix thoroughly. Repeat for rest of cabbage.

4. Twist the bag of cabbage closed, place in sink to brine for 5 hours. As by bag had some small holes, evidently, the brine drained off, more or less.

5. After 5 hours, squeeze out excess moisture and brine from cabbage (and you should rinse it at this point). I didn’t rinse, as my radish was very large, relative to the amount of cabbage, so I felt it would absorb the excess salt that would have been rinsed off.

6. Mince and mash garlic and ginger, slice scallions (green onions) to 2.5 cm pieces – cut the lower, white part lengthwise first. Peel, quarter, then shred radish.

7. In large bowl or tub, mix brined cabbage, garlic, ginger, scallions, radish, sugar and fish sauce (I forgot to buy shrimp paste, so added a bit more fish sauce).  Add chile powder – I first added about 4 tablespoons, then felt it did not look red enough, so added another two. This is a bit vague, I know, but I think it will depend on how much cabbage and radish you have used.

8. Put mixture in clean container, that is not fully closed (to allow gases to escape). Store in cool place for several days while it ferments, then place in fridge. Enjoy?

Here’s a few pictures of the process, and the result:

May 7, 2008

Long-Winded Soy Sauce Update

I’ve been digesting what Kikkoman said to Inigo for a few days now, as well as what Takadi has asked (sorry about not responding earlier…it has been busy!).

Kikkoman initially says: “we suggest that you use 30 g of salt per 100 ml of water used”. In other words, 30% salt (by my weird calculation) or about 23% by weight.

Then they say: “it is recommended that you use at least 15 to 16% salt, otherwise the moromi mash could decay”.

This made me panic a bit, as my salt concentration, by weight, was only 6.25%! The fermentation has been producing a fairly strong sour smell (or as my wife described it, ‘cheesy’). This is most likely from a vigorous lactic acid bacterial fermentation. As I have mentioned earlier, it was re-forming a pellicle every day (which I would break apart during stirring).

So, I drew off about 800 ml of brine and boiled it with 350 g of salt. As not all the salt was dissolving, I added probably about 200 to 250 ml of fresh water. This I then added back to the fermenting soy sauce, raising the total salinity to about 15.2% (by weight – as you may have noticed, I have stopped using my odd way of measuring salt %!).

I have definitely killed off any visible microbial action now! And it obviously tastes very salty now – in fact saltier than my Kikkoman soy sauce. On the other hand, it does not taste bad at all – it is kind of like a mix of miso and soy, with some extra acidy. Or something like that anyway.

This brings me back to my ‘back of the envelope’ calculation of the salinity of the Kikkoman soy sauce. I have to swallow my pride and say that my memory of chemistry is abominable! Here’s what I said: “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%“. Wrong. The atomic mass of sodium is 22.99 g, and chlorine’s is 35.45 g – or over 150% larger! Recalculating the salinity meant going back to the label to see that there were 920 g of sodium in 15 ml of soy sauce. This is actually 6.1% sodium, there would thus be 6.1% + (1.5 x 6.1%) salt, but wait, salt water is denser than fresh water. Again taking a short cut (this will probably end up haunting me later), I found that regular sea water (3.5% salt) is about 2.8% denser than fresh water, and dead sea water (33% salt) is about 17% denser. I just used the average – so I estimate that the soy sauce is about 10% denser than fresh water.

Getting back to the question at hand – this means that Kikkoman’s sodium % was about 5.6% (920g / (1.1 x 15000ml)), so the salt concentration must have been around 14% (5.6% + (1.54 x 5.6%)). Ah Ha! Kikkoman may have been giving Inigo some funny numbers… 14% salt is WAY less than the 23% they recommend, and perhaps even below the level at which they claim the moromi mash would decay (remember, my calculations are not exact)! Maybe they dilute their soy sauce prior to packaging? Maybe European soy sauce is much saltier than North American?

And back to my observation that my 15% soy sauce is noticeably saltier tasting than Kikkoman’s (although not so much as to be unpalatable). This is especially interesting as I use sea salt. Mark Bittman*, in “How to Cook Everything Vegetarian, states that sea salt tastes less salty than table salt. Hmmm…that means that my soy sauce’s salinity may be higher than I calculated, or Kikkoman’s lower. I think it is likelier that my soy sauce’s salinity is higher, as I have not been measure the volumes of water I have removed or added very accurately, and further, water has evaporated over the past few weeks.

Switching gears, takadi asks:

I think it’s interesting you mention the differences between chinese soy and japanese soy and compare it almost to the differences between an ale and a lager. Perhaps that’s why Chinese soy sauces tend to be more robust and Japanese soy sauces more delicate. Would the ratio of wheat have anything to do with the fermentation process either?

I’m really not a connoisseur of soy sauces – this whole experiment has been an eye-opener. As you say, it does sound like Chinese and Japanese soy fermentation styles differ in a way like ales and lagers do. However, I cannot really say much further, as I don’t know the differences well.

The wheat is a bit of a wild card for me, in terms of its effects. I think that in traditional soy sauce making, wheat flour provides a good innoculum source for wild yeasts, lactic acid bacteria, and molds – all of which grow naturally on wheat grains. Without a reliable source of starter/innoculum/koji, farmers may have had to do with what was available. Further, wheat is likely a source of easily assimilated carbohydrates for the molds to feed on, before they are able to attack the soy beans. Unfermented soy beans are not easily digestible by humans, and it may be the same for micro-organisms. Once a culture of micro-organisms has been developed, it is likely that they are adapted to eat pure soy beans, no longer requiring the initial availability of wheat. The wheat may also make it easier to form the loaves. Finally, the wheat may survive to the fermentation stage, providing sugars for yeasts and bacteria to produce alcohol and acids, which creates ‘sanitary’ conditions inhospitable to less desirable micro-organisms. Early farmers lacked access to sanitizers or preservatives, making this last point important.

When you talk about percentages of salt, do you mean percentage of salt in the brine, or percentage of salt total including all the other ingredients?

Good point. Sometimes one, sometimes the other. My own brine was calculated ignoring the other ingredients, while my calculations of Kikkoman’s salinity include the other ingredients (I don’t know how much they weigh). I don’t feel like revisiting my salinity calculations right now, but I may later.

It seems as if this method relies on wild yeast strains similar to creating sourdough starter. How would effect the flavor?

Yes, this method does feel a lot like making a sourdough starter. As I mentioned in the first post, the soy patties initially smelled like my failed sourdough starter (it turned into a salt-risen bread starter). Salt-risen bread is fermented by clostridium bacteria. It makes a very cheesy tasting bread, so perhaps this has contributed to my wife’s opinion that the soy sauce fermentation smells cheesy. The cheesiness probably also comes from lactobacteria. Last weekend I tried a local brewery’s sour beer (fermented partly by lactobacteria) and it smelled cheesy. It was (personally) very over-soured – although very nice when diluted with their lager by 2/3.

“I’m also wondering how tamari is made without the addition of wheat to aid in the process of inoculating a culture.”

I really can’t say. As I say above, perhaps when a starter culture has been used for a while, it adapts to its conditions and is able to digest pure soy.

“…how do you keep the loaves warm in order for the strains to take hold?”

I kept them on top of my fridge, where it is a bit warmer. I don’t think you need to worry much about mold taking hold on your soy patties! 😉 As children discover in their school lockers and at the back of fridges, most foods get moldy sooner or later.

“Do you think keeping the mixture inside an open glass jar would be a different environment than keeping it in a plastic tub? There would definitely be more sun exposure.”

I do think it would give more sun exposure, which by definition is a different environment. In fact, my grandmother just gave me a huge glass jar, and I have transfered the soy sauce into it. As the jar is much smaller than the bucket, I could bring it inside and fit in the window. Besides, you can see what is going on much better. It also seems somehow more ‘respectable’ when it is in a glass jar, rather than in a bucket!

* Bittman’s cookbooks are the only ones I use regularly. Incidentally he has a blog at the NY Times, in which he posted a link to canucklehead’s soy sauce making directions – way to go canucklehead! – around the same time I was starting to make soy sauce.

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.

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