my thoughts on a serious rice wine attempt

So, I was studying AK-Taylor's masterpiece on real sake brewing along with as much info as I could find about korean rice wine, makkeoli. I was looking at understanding how koji/nuruk's aspergillus oryzae converts starch to sugar as best as I could.

I put together a recipe that is essentially like sake, but uses nuruk instead of koji (i'm in korea). I wanted to avoid sourness, and turn this into a pasteurized high alc rice wine so I looked at when to set temperatures to what.

So far it has worked alright, the feeling of it is like working up a high ferment and keeping it there with continuous additions of fermentables to stave off sourness, then cold crashing it to let it rest/ferment out while ensuring the lacto stays dormant. it feels different from brewing beer big time. took a sample after 2 days, tasted very mild and just slightly tart.

i'll update with pics and my methods soon. i thope it's a good hybrid of a serious rice wine but not as painfully difficult as AK-taylor's sake instructions.

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The thing about using nuruk, just like the Chinese and Vietnamese yeast balls, is that they are a mixture of regional bacteria, fungus and yeasts. You must be careful of the type of nuruk you select as many types have pathogenic bacteria in them. Many varieties also contain no Aspergillus whatsoever. Here is a link to an abstract that tested a wide sample of Korean nuruk for microflora analysis. You might find it interesting.

The reason that the Sake masters in Japan can produce a traditionally made consistent Sake is through very tight and strict controls over the process, including the ingredients and the strains of fungi and bacteria they allow to "infect" their rice.

That being said, I wish you success. With the wide variety of microflora in the nuruk, it's going to be interesting if your success can be repeated with consistency.

Right, to answer your question. I forgot to mention that I had a rice wine yeast starter in addition to the nuruk. However, I know that nuruk is full of all sorts of critters. I bougt mine unbagged and in the form of a 1'x1' rock hard cake.
Truthfully, one thing I was wondering about was if a yeast starter made from a commercial and unpasteurized makkeoli would have any living a. oryzae in it and be able to saccharify? I still don't know the answer on that yet.
But anyway, the steps so far
1. made a yeast starter using DME and a local, unpasteurized, bottled the previous day makkeoli. It's a great tasting one, not like the garbage sold in big white bottles or most commercial makkeolis. The starter took off pretty fast.
2.Soaked thoroughly cleaned short grain rice for 2 hours in fridge. washed it off some more and steamed it for 45 minutes. ended up being chewier and more firm than al dente noodles but squishable.
3. Using idophor sterilized equipment I mashed up about 150g of nuruk into 1kg of steamed rice. Put this in the carboy with 2 litres of bottled water. raised temperature using water bath to 35 degrees celsius. I read that the correct amylase for saccharification is produced between 35 and 38 celsius. kept it there for 3 hours.
4. cooled it down and added the yeast starter.
5. let it sit for 24 hours at 70 degrees F. it was fermenting vigoruously but without a krausen. about 10% of the rice were "dancing" along the top of the carboy.
6. stirred it once with a sterilized paddle and put it in a 50F fridge.

Next: It is now resting in the fridge at 50F to inhibit lactobacillus (I hope) and waiting for the next addition of 1kg of steamed rice, water and maybe 200g nuruk. I will do this next rice addition and then one more, eventually make a rice wine of about 18% alcohol about 7 litres of end product

probably stuff I did that I missed, but it's a new process to me.

Oh, and I got a lot of "advice" from koreans who saw their parents make it once or twice or have the general idea of homebrewed makkeoli. none of them aware of modern homebrewing methods or sterilization, and I mostly just smiled and nodded. I think makkeoli has a bad rep because only just recently have worthwhile makkeoli breweries come up. the grandma's homebrew stuff and pasteurized industrial garbage I can easily pass on.

third and last addition added to the fermenter. at the second one it was just slightly sour, now it definitely has sourness, which i didn't want. im hoping to let it continue 2 more days then serve some up as high strength makkeoli. filter a bit more and pasteurize the rest.

i think i blame the nuruk, either using too much or just for its inherent properties.

next time i'm definitely using koji.

i'll post pics and the process details after i pasteurize it

I have never used nuruk before but I did make my own version of the Chinese yeast balls from wheat flour, aspergillosis oryzae, Penicillium Roqueforti & some lees from a previous Sake batch to introduce the yeast. I used a very controlled process in creating my Jiuqu rather than how nuruk is made which I have read is often a wheat block wrapped in dried corn husk with white or yellow molds growing over a 2 week process and throwing out any black molds.

I noticed that the rice/wine I made was definitely more sour but I also noticed that the wheat broke down into long chain fatty acids and gave an oily feel to the lees. I was not impressed. If I ever made some traditional Nuruk or purchased it then I would probably do a much more controlled and colder ferment. Possibly only give the yeast and enzymes a 12 hour warm start at each nuruk/rice addition and then cool it down closer to the 40*F - 45*F range for the largest portion of fermentation.

Just my 2 cents.

Ok here's what you've been waiting for, my notes on how to and the level of success of this rice wine

before you read any further, i'm now quite happy with how this turned out. It is a very easy and nicely flavoured alcoholic beverage.

Ingredients to begin with:
-3kg short grain korean rice (food level of polishing-mid 90%?)
-about 500g of nuruk (half of a big hard wheaty-cake-cost 2 dollars for the amount i used)
-7 or 8 litres of bottled water (low minerals, 1ppm or less iron)
-yeast starter of local, unpasteurized makkeoli yeast

there are 6 steps i'd say, though frankly all but the 5th are quite easy. they are modeled after japanese sake brewing, which steps up the brew in amount so as ferment as efficiently and cleanly as possible. i used brewtarget (software) to estimate the potential i would get from 3kg of rice in the amount of water i used, and it should be in the range of 16% alcohol. i also kinda winged this based on how i thought the progress was going...

1.0 - yeast starter (day 1)
made yeast starter from very fresh makkeoli with DME just like i would with a beer yeast starter. starter worked really fast (hours)
this part i know will be the hardest for those trying this outside of korea or japan, but otherwise i guess use sake yeast or a lager yeast

2.0 - first addition of rice/nuruk (day 2)
-Soaked 1kg thoroughly cleaned short grain rice for 2 hours in fridge. washed it off some more and steamed it for 45 minutes. ended up being chewier and more firm than al dente noodles but squishable.
-Using idophor sterilized equipment I mashed up about 150g of nuruk into 1kg of steamed rice. Put this in the carboy with 2 litres of bottled water. raised temperature using water bath to 35 degrees celsius. I read that the correct amylase for saccharification is produced between 35 and 38 celsius. kept it there for 3 hours.
-cooled it down and added the yeast starter.
-let it sit for 24 hours at 70 degrees F. it was fermenting vigoruously but without a krausen. about 10% of the rice were "dancing" along the top of the carboy.
-stirred it once with a sterilized paddle and put it in a 50F fridge.
-continued to stir it about once every two days with a sterilized wooden paddle.
NOTES: This is what I did, however looking back at the other additions I made, I don't know if leaving it out for 24 hours was necessary, as for following additions of rice and nuruk, it worked at a low temperature (50F).
-smells like fermentation of some kind, fairly mild.

3.0 - second addition of rice/nuruk (carboy is now sitting in the fridge permanently) (day 4)
-Soaked 1kg thoroughly cleaned short grain rice for 2 hours in fridge. washed it off some more and steamed it for 45 minutes.
-Using idophor sterilized equipment I mashed up about 200g of nuruk into 1kg of steamed rice. Put this in the carboy with 2 litres of bottled water.
-stirred it with a sterilized paddle.
-continued to stir it about once every two days with a sterilized wooden paddle.
NOTES: tastes fresh, zingy but not sour by this point, taste of alcohol is moderate.

4.0 - third addition of rice/nuruk (day 8)
-Soaked 1kg thoroughly cleaned short grain rice for 2 hours in fridge. washed it off some more and steamed it for 45 minutes.
-Using idophor sterilized equipment I mashed up about 150g of nuruk into 1kg of steamed rice. Put this in the carboy with 2 litres of bottled water.
-stirred it with a sterilized paddle.
-continued to stir it about once every two days with a sterilized wooden paddle.
NOTES: a week after this third addition, it tasted pretty distinctly sour but drinkable. as sour as mild lemonade, but complex and tasty. by day 14/15 i noticed that visible fermentation (bubbles and rice dancing) had stopped, most of the rice had turned to mush/powder.

5.0 - straining out rice refuse/secondary (day 16)
-this part i thought wouldn't be so bad, but it was a huge pain because i didn't really have a great plan.
-i used a big nylon bag to try to hold back the used up rice and solids while upturning the carboy to drain out the liquid. it worked for a while before it just became too slow of a process and the carboy too heavy to hold up. hard to describe, but siphoning it is simply not an option, the rice mass was a total pain to grapple with. i ended up sanitizing plastic gloves and squeezing little handfuls of rice into the secondary to extract as much rice wine as i could. demoralized by this seeming failure i didn't really try hard, but ended up with about 5 litres of liquid or so. my tasting notes were: rice, earthy funkiness, quite sour up front but turns into alcohol, some richness. ends with a big alcohol burn
-gravity at about 0.996

6.0 - separating clearer liquid, pasteurizing and bottling. (day 22)
-it separated quite well after the secondary process and i siphoned the clear liquid into another container to clarify it fully.
-took clear liquid and siphoned it into bottles, pasteurized bottles by inserting uncapped bottles into my brewkettle fairly full with water and slowly heated them to 140 degrees fahrenheit. CO2 bubbled out of the bottles the whole time, as each bottle reached 140 i took them out and left the cap to sit on them for a bit then bottled them. the remaining solid heavy liquid i bottled in sanitized water bottles and refridgerated.


day 30 - the rice wine lost all the unpleasant sourness after being bottled for a week, tastes alcohol heavy, not fruity but earthy and a lot like sake and with the distinctive yeast of my locale (which is a plus in itself). it doesn't drink like a beer and i enjoy it in small cups, often refilled. the alcohol hits you hard and gets you drunk fast.

this ended up great, and i think i cut out a lot of the seeming and real complexity that other sake guides (despite my indebtedness to them) offer.

Sounds great! Gratz on the successful brew. I am glad to hear that sourness went away.