Misleading Specific Gravity (maybe)
- I have just finished a disappointing spirit run on wash made from corn starch. I got about a quart of drinkable product with a really good taste.
I dumped 15 pounds of corn starch (the package label said it was pure and without preservatives) in 8 gallons of hot water and heated the mixture. When I reached my target temperature, I added amalyze enzyme, managed the temperature, stirred, took my time and as far as I could see, I converted the entire 15 pounds of insoluble corn starch to soluble corn sugar. I based that assumption on there was no sediment in the bottom of my cooking pot after 24 hours and the wash tasted really sweet.
Using backset I had saved from an all-grain bourbon run, I brought the volume to 10 gallons and aerated for 24 hours with an aquarium pump. The starting temperature was 80 degrees F. The starting specific gravity was 1.026. I added 4 tablespoons 24-8-16 water soluble miracle-gro and pitched two packets of bakers yeast.
I let it ferment for about 3 weeks. When I checked the wash, it smelled right. It had no sweet taste, but had a grainy after taste. The temperature was 72 degrees F, specific gravity was 1.020. I thought the ferment was stuck, so I heated the wash to 80 degrees F, added 4 more tablespoons of miracle-gro and pitched two more packets of bakers yeast. I let it ferment another 10 days. When I checked the final specific gravity, it was still 1.020. The wash smelled and tasted right and the grainy after taste was gone. I transferred the 10 gallon wash to two 5 gallon buckets, let it clear for 3 days and then decanted it into my still tank. I ended up with a full gallon of trub.
When I started the fermentation, I figured the final specific gravity would be 1.0 or less. I guessed that after dilution, I would end up with about of a gallon of drinkable product. In this case, the starting specific gravity must been the result of something other than sugar. I have no idea what that something is. Would appreciate it if some one had some thoughts on why the starting specific gravity was so misleading.
I think this process has some merit. I think you could end up with pure corn whiskey, without all the work involved when using grain. I only spent $21.00 U.S. on the materials and the product I got was quite tasty. I would like to try it again, but with greater success. Any guidance on how to reach that goal is appreciated.