Mold on Rice Wine Ferment

[Wissahickon]

Recently I attempted to make rice wine, using sweet rice purchased from an Asian market, and the round white yeast balls also available there, usually sold in packets of two yeast balls. I made this rice wine long ago, in the 1980s, and it worked well. At that time, I used a glass bowl for the ferment vessel. This time, I selected a two quart mason jar for the fermentation vessel, followed instructions for making the rice wine, and began the process. All seemed to go well, except that there was a spot of dark mold on top of the ferment, about the size of a nickel, when the process was completed. I tasted but did not swallow the rice/wine, and there was no off taste or smell. I wonder whether the mold was the result of my using a tall and narrow vessel rather than a broader one, which might have allowed all the rice to be completely submerged in the liquid. Anyway, I scraped the mold off, screwed the lid on the jar, and refrigerated it. But I haven't yet used the rice wine (intended for cooking purposes, not for drinking). I wonder if anyone has any thoughts about this very rudimentary issue in fermenting wines. Any suggestions would be greatly appreciated.

[khooleos]

From my experience, either a drop of sweat or saliva got into the mix. No worries at all. Shape and size of container matters little as the rice 'island' will sink eventually based on how long your fermentation process is.

We've been making 'tuak' for close to 5 years now and I have to say that the yeast strain of the 'chao peng' (yeast balls) is far more robust than that of wine yeast. They settle into their medium and cultivate extremely fast thereby hindering unwanted mold spores from the air. Never had a stalled fermentation once.

On a related note a friend of mine also found black mould spores on his fermenting surface. A bit agitated he tried to recall what he might have done different and realized he was on his hp while stirring in the syrup into the starter culture. There is a taboo from my grandma's time which states while making rice wine or any other ferment ; "Smile always and never fight or shout in front of the fermentation pot." Now you know, and knowing is half the battle.

[Wissahickon]

Many and sincere thanks for this response, khooleos! I plan to experiment much more with the chao penh yeast. I've saved the original ferment, opened and smelled it recently, and it smells sweet, and very fine. I'll put it to use in cooking soon. I suspect that since it's been in the refrigerator for a number of months, that it's matured and developed a smoother flavor. I'll let you know.

Wissahickon

[Algoldor]

Hi Wissahickon,
I'm not sure what is the microbial composition of the "white yeast balls" which you are describing but based on my experience of preparation of traditional rice beer in South Korea (where I live now) called makgeolli (in Japan you could use the word "doboroku" which is unfiltered=rice left in), the traditional culture which is used for the fermentation is nuruk on wiki you can find it under the term tapai. This culture comprise of both bacteria and fungus and as part of the fungal kingdom yeast. I have to say that I have never had a contamination with a mold on the top of my brew but I know well that if you use the traditional rice cakes (nuruk) from the market, they have both white and green molds on it (in different shades). Therefore if some of them became bit too enthusiastic and made it to the top of your brew, I would not be too worried, taste should tell you. The style of fermentation in this part of the world is very different from Western one especially the rather minimalistic use of sterilization techniques and relaying on wild fermentation is quite "another cup of tea".

I hope that you will succeed in your experimenting, you may try to make your own nuruk, it takes time and practice (which I do not have so much) but it is fun!

Sincerely from Jeju,

Frantisek Algoldor Apfelbeck

PS Just a note, most of the rice beers (wines) are consumed within a week or at max a month after finishing the fermentation even if you keep it in the fridge. You can keep it longer but it is not done very often.

[Wissahickon]

More on the subject of rice wine... I've kept a batch of rice wine in my refrigerator, and haven't strained the wine -- so the lees remain in the jar with the liquid. I've kept this on hand for a couple of years now, for various reasons. My question is, can I still use this very "mature" wine, and also use the lees for cooking, or even for drinking? Does home brew rice wine lose potency, flavor, or healthfulness over time? Even more to the point, does it remain safe to drink after several years of refrigerator storage? I'm reacting here to Algoldor's caution, if it was a caution, that people consume their home brew rice wine within a month or so of fermenting it. I'd appreciate any thoughts or suggestions members may have. Thanks!

[boschmas]

I made one batch of rice beer or wine that didn't turn out that well, so my experience is quite limited, but as for the aging part.... My sense is that a lot of the quick-consume traditions with alcohol are entirely centered around the lack of refrigeration and an inability to control for vinegar microbes in the home (since these things all predate germ theory).

As with everything else, if your refrigerated rice wine continues to smell and taste okay, let your senses be your guide. If there are off smells or flavors or signs of mold, those should be important signals that your ferment may have reached the end of its life.

[Wissahickon]

Many thanks, boschmas. Interestingly, the wine tastes slightly sweet, and smells fine -- and it's probably two years old by now. Your advice is on the mark; I do some fermenting of various things, and have done so for the past several years, but it appears that I haven't yet fully made the leap into the intuitive comfort zone that you and others, such as Sandor, suggest, though perhaps I'm slowly getting there. I'll take another sip of the wine, use it as needed (mainly for cooking), and monitor it intuitively. Thanks again. W