It was not a total failure. The fact that I got eight ounces this time, rather than two, means that homemade brown rice syrup will be economical when all is said and done. By rough calculations I figured that this eight ounce jar cost me $1.21 to make (not counting labor and electricity). So a full sized jar (16 ounces) would cost $2.42. I still haven't been successful at converting all of the starches so when I do, the yield will go up even more and the cost will come down.
Even though this turned out muddier than the last one, it is sweeter and less bitter. The reason it's muddier is because I ground the rice into flour and so some of the unconverted starches were small enough to slip through during the straining process.
Here's what I did this time. I ground a cup and a half of rice into flour with my coffee grinder, then cooked it in nine cups of water for about twenty minutes. I let it cool until the temperature in the center of the pot was below 150 degrees Fahrenheit. Then I added the sprouted barley.
This time I also did something different with the barley. On various websites that talk about how to malt barley, they say that once the barley is sprouted it's dried in order to halt the process at the right point. I haven't been doing this, since I was using the barley immediately and didn't think it mattered. But this time I dried the barley in the oven for several hours (keeping the temp below 150F at all times). Whether this is a critical step or not, I don't know. But it did have one obvious benefit--when it was dried I could grind it into a fine powder in the coffee grinder. That made it possible to disperse it more uniformly in the rice mixture.
So I mixed the barley powder ( 1/4 of a cup) into the rice mixture and put it in the oven, where I kept the temperature somewhere in between 140 and 150 degrees. I let it cook for seven hours then turned the oven off and left it there overnight. (The only reason I didn't cook it longer is because I was heading to bed). In the morning I strained it. This time instead of using cheesecloth I strained twice through my regular mesh sieve and twice more through a really fine sieve (one of my little two-inch diameter tea strainers--a little tedious!). Still, some of the starches were fine enough to get through. This yielded six cups of liquid, which seemed like a promising amount to start out with. From that I was hoping to yield at least twelve ounces of syrup.
It took about forty-five minutes to boil it down and in the end, as I said, I got eight ounces. It's the sweetest batch so far and also the least bitter, so I know I'm on the right track. I really think the bitterness is coming from the unconverted starches rather than the barley. There still was quite a lot of rice sludge that I filtered out--at least a cup, maybe a cup and a half.
So, next time... (while I was working on this last night my friend John called and I told him there wasn't going to be a next time, but he launched into the "What if Thomas Edison had given up after a few tries, what if Albert Einstein had given up after a few tries" spiel. I told him it's not quite the same--this thing has already been invented. There's really no need for anyone to do it again. But, sigh, I am quite a persistent little bugger so I will probably keep at it until I figure it out.) Anyway, I was saying, next time I'm going to up the amount of barley maybe to as much as half a cup and I will also let it cook indefinitely. The worst thing that will happen if it goes too long is that the sugars will start to convert to alcohol. If I keep tasting it as I go, I should be able to tell when that starts to happen. Then I'll know for the next time to stop just short of that.