...Experience with an AG mash.

[zed255]

Well, the time finally came. A form of graduation was upon me. I decided it was time to move onto my first experience using grain.

What grain you ask? Well, for convenience and economy I chose rice, and the fact I had liquid enzymes to use. So, following a client visit I found myself near my areas largest Asian grocery and went looking for some decent sized bags of rice. Settled on two 6.8kg (15lb) bags of Calrose, a well polished short grain variety at $10.98CAD each.

Of course, I had been reading various threads pertaining to the use of rice and the myriad of experiences contained therein. My initial attempt was a salvageable failure. I had read of folks using a cooler and boiling water to cook the rice, introducing pH adjustments and enzymes at the appropriate times. Well, whether it was my protocol or some other factor I can't say, but what I do know is that there was no way in hell the rice was going to cook for me that way. I had to bail on that plan and get into it right proper. Below is an outline of my first go at an AG mash.

Firstly, I knew I had to get my grains properly gelatinized (cooked), so I just split up the aforementioned batch of rice and liquid by four. I had read about some less than ideal conversions, so I was working at 2.5lb/gal to try and achieve an OG of about 1.075. I brought this up batch-wise in a stock pot to a gentle boil which I held for about 20 minutes. In this case enzymes were present while re-heating the mix, but I expected to denature them fairly quickly. After this initial cooking I used and immersion / stick blender to break up the rice grains without making total porridge. I allowed this to cool off to 190F and checked my pH. I added the SebStar HTL high temp alpha amalayse and transferred into a cooler to rest while I did the remaining grains likewise.

After completing the full cooking / gelatinization of my rice I removed the lid from the cooler and allowed the mix to cool to 150F. I slightly lowed pH for the gluco amalayse and added it in (I also has SebFlo and used it too) and covered the batch for the night.

Come morning I go check on the batch. Still too hot to pitch yeast, but when I checked my OG I was shocked to see 1.086 in the refractometer. I pulled clear liquid and cooled it to recheck with the hydrometer and sure enough I had 1.086 for my OG. My use on enzymes was most certainly excessive but I'm not arguing the results.

My volume was too great for a single small fermenter and less than I like in a big fermenter, so I decided to split the batch into multiple small fermenters. This allowed me to adjust my OG to my 1.075 target and get down to pitching temperature quicker by just adding some cool water. Vigorous aeration for 10 minutes while the yeast was rehydrated in a diluted sample of the mash and pitched when activity was apparent.

Now the wait to see what this turns into. I now need to decide whether to reflux it to see what kind of neutral it makes or pot still it and see what kind of character the rice spirit has. Opinions or thoughts?