Although I am a novice at the art of distilling, I am a brewmaster and am very familiar with what exactly is happening during a grain fermentation.
Dnderhead is correct in saying that your wash should taste dry when it is done fermenting. This is because all of the sugars in your mash have been converted to alcohol.
MuleKicker wrote:did you get good conversion? Did you do an iodine test or anything? did it bubble shortly after piching yeast? Like dnder said, what does it taste like?
What MuleKicker is referring to is adding Iodine during the conversion process. Iodine fills the inside of the helix pattern that starch forms and causes a dark purple or black reaction. Short sugar chains do not form this coil and should not react with the iodine. Take a laddle and dip into your mash and place this on a plate. By adding one or two drops of Iodine to a plate of your mash, you can tell whether or not you have starches in your mash by whether or not the plate turns black/purple.
After you have converted our mash and pitched your yeast, you should have a significant amount of foam arise from the fermentation. This heavy foam cap is called the Krausen and lets you know the yeast are producing CO2. If you picthed your yeast at too high of a temperature and killed them (or if they never had any converted food to ferment), you may not have gotten a kick-start on your fermentation, and thus, no Krausen.
You should take a hydrometer reading from just liquid. Particulates in the mash may throw off your measurement if they sink, float, or stick to the hydrometer. At least in the beginning, you should always take a SG (starting gravity) when fermenting anything if you want to know how much alcohol is in it after fermentation.
I think I know these hydrometers you're referring to. They have SG (specific gravity), °P or °B (degrees Plato or Brix), and % potential alcohol. I believe the local home brew shop calls them "triple scale hydrometers." The first thing you should do is get a better hydrometer. These are small and are not very accurate. The larger your hydrometer, the more liquid is displaces and the larger the change in flotation from a change in density. This larger change equates to a higher resolution on your hydrometer. (I will post pictures of mine when I find my camera cord).
The only way to accurately determine the alcohol in your wash (other than Real Extract Analysis, which is beyond the scope of this forum), is to calculate based on the change
in SG, °P, °B, or %pot.alc.. It should be obvious that the tool you are using (the hydrometer) is measuring specific gravity. The more carbohydrates in the solution (or anything, you can use hydrometers to determine the amount of salt in your aquarium), then the thicker the liquid and the higher the device floats. This drop in density signifies the sugars dissolved in the liquid being turned into CO2 and alcohol.
If you do a search for an alcohol calculator, you should find something that allows you to punch in your SG and FG (starting gravity and final gravity) to give you a % alcohol by weight or volume. This is also more accurate than using the %pot. alc. part of your hydrometer because your final gravity may vary greatly (it may be below 1.0000 SG / 0.0°Plato or you may have a stuck fermentation and it could be 1.010 SG / 2.5°Plato or even higher). The best solution is to get hydrometers that very accurately measure in SG or °P (degrees Plato). °P represents (very closely at low gravity) percent sucrose by mass. The formula for %alc. is much easier when dealing with changes in °P or °Brix versus changes in SG. Although °P or °B aren't a perfect multiple of specific gravity, usually .004 SG represents 1°P (so 1.040 SG would be 10°P, and 1.060 would be 15°P). Most brewers' s saccharometers have thermometers inside of the hydrometer to give a temperature correction. If your sample is colder than the hydrometer requires, the fluid will be slightly more dense, and the hydrometer will float higher and give you a higher SG (or °Plato). If it is hotter, the fluid will be less dense and the hydrometer will sink deeper into the sample and give you a lower reading.
GAshinner wrote:yes the mash was cooked. thanks for all of the replies. what do yall think about shaking or stiring the mash. will this help or should i leave it sitting alone undisturbed?
Stirring your mash may help to agitate some of the settled yeast and restart fermentation. However, if you did not have a proper conversion to begin with, you will not be able to ferment these starches. Also, continuous agitation during the entire course of fermentation can lead to higher fusel alcohols.
+1 WW... Old timers never had the luxury of Hyrometers/Alcometers/Vinometers/Etc, instead they just used their senses... Once the convertion was done it tasted sweet and after the fermentation stage, it was bitter... I use a Hydrometer on my wash's, but I always taste, especially after fermenting on the grain...
If it started fermenting for you and it tastes bitter, then I would run it... As WalkingWolf said, the hydrometer will give you an approximation of the starting gravity/finishing gravity, due to all other compounds in the wort... From that you will be able to calculate approximately the abv in your wash, this will give you a heads up, allbeit limited, when you run it...
Hope this helps GAshinner....
Let us know how you get on man...
You should taste your mash after conversion to make sure it tastes sweet and that your starches in your grains have been converted to sugars. After fermentation, these sugars have been converted to alcohol and there should be no sweetness. The bitterness that Samohon is referring to is the tannins that have been extracted from the husks of the grain during fermentation.
I definitely agree that we are spoiled with technology when we can determine specific gravity to a 0.0001 resolution or temperature to 0.1°F with a device that cost under $100.00. People would have killed for that hundreds of years ago.
If you have already (supposedly) fermented your wash, then you can tell if there is alcohol in it by two separate tests. You must take a very accurate SG (specific gravity) reading and a refractometer reading. Usually the highest resolution hydrometers and refractometers for brewers/vinters/distillers measure in °Brix or °Plato. Because you have alcohol in your wash (hopefully), the readings for each device will be skewed (the hydrometer being lower because alcohol is lighter than water, and the refractometer higher because alcohol is more refractive than water) and should not give you the same numbers. By plugging these numbers into a very complex equation (just find a program called ProMash and use the %alc function) you can find the original specific gravity before fermentation (starting gravity) and the percent in alcohol by weight or volume.
My point is, you must have two of the following:
to find % alcohol.