Soy Sauce mash fermented for a year ... safe?

[Johntodd]

Hi! When I was reading an old logbook, I came across an entry for me making a soy sauce mash. That entry was 12-November-2012. I had forgotten the mash was even there.

Well, I found it. It is black and fully "mashed". Is it still safe to make into soy sauce?

It has been sealed in ziploc bags the whole time. I doubt any air has gotten to it. Perhaps I should boil it for a while before letting it go to the next step?

Thanks!

-Johntodd

[Ttogull]

I am not an expert, but that never stops me!

First, I'd think about asking a more specialized forum, perhaps like the one at wild fermentation.com, especially on the issue of safety.

Second, as I understand things, boiling it will kill the bacteria that make it safe -if indeed it is safe - and afterward you'd have to use sterization techniques for canning and so on.

Good luck!

[Lisa Shock]

I'd worry about aflatoxin, but, I have no idea how length of time in soy sauce making affects its presence or lack thereof.

[Ttogull]

Do you mind sharing how you made the mash? As I understand, making soy sauce is the same as making miso. I like (high quality) miso, and entertained making it myself.

The thing is that, if you did things correctly, there seems to be no indication of a safety issue in your case. A taste issue maybe, but that is different. A couple of sources mention a post pasteurization if it makes one feel better, but as I said before this seems like it would kill all the good guys.

I am curious how you set it up. Did you use koji? Or did you let bean cakes mold as some recipes call for? I am interested because I'd prefer not to use store bought koji, and I like to use nontraditional beans and spicing. A Mexican miso perhaps... Heresy, I know!

[Johntodd]

My method was "all natural". I boild the beans until soft, drained them in a colander, smushed 'em up, and put them in bags.

So I've no idea what microbiota is doing the fermenting.

[Ttogull]

My method was "all natural". I boild the beans until soft, drained them in a colander, smushed 'em up, and put them in bags.

So I've no idea what microbiota is doing the fermenting.

I've only done a little fermenting, but your method seems a bit suspect. I wouldn't touch them. The fact that they have been fermenting for a year seems to be a bit of a red herring.

[Johntodd]

I agree. Unless someone more knowledgeable than me chimes in, I think I'll dump the stuff.

[Keith_W]

I have lost the reference now, but I think that Chinese and Japanese soy sauces are fermented for a couple of years in earthenware pots. If I find it I will link it. Or perhaps one of our Chinese members can chime in.

[heidih]

I think pitching sounds wise. There was some interesting stuff in our homemade soy sauce topic http://forums.egullet.org/topic/103707-making-soy-sauce-at-home/

[Ttogull]

I have lost the reference now, but I think that Chinese and Japanese soy sauces are fermented for a couple of years in earthenware pots. If I find it I will link it. Or perhaps one of our Chinese members can chime in.

They can be fermented for years after attracting good bacteria, etc., that make long term fermentation safe. Simply storing this stuff after cooking, As I understand the OP did, is not necessarily safe. It's like canning without following any of the sterilization procedures. In this case, how long the OP stored it seems to be a minor issue compared to what he did before storing it.

ETA what I mean is, after cooking the OP needed to inoculate the beans with either koji or by letting mold grow on it, as indicated in the related thread mentioned above

Edited August 22, 2013 by Ttogull (log)