Next video in the Heads series: |How to use an alcoholmeter|
Hi folks, and welcome back for another Heads episode. Along with the alcoholmeter, the hydrometer is one of the most important and cheapest tools that you can buy. The hydrometer measures the specific gravity of water that has some sugar content. This is usually your mash before you ferment it. The hydrometer can help you measure the specific gravity of water with sugar in it. This specific gravity will help you get an estimated alcohol by volume of your mash once it has completed fermentation.
So, the basic way that the hydrometer works is that it is a glass tube that is hollow, with a weight in the bottom. It is calibrated to plain water, so, basically, when you put it in just plain old tap water at a certain temperature, it will rest at a certain level, which is this 1.0 mark at the top. As you add sugar to the water, the density of the water actually increases and the hydrometer will float more, revealing a potential alcohol by volume, a brix number, or a specific gravity number. This is a triple-scale hydrometer, but you may also find them in double scale or just single scale.
So, to demonstrate, we’ll add water to this test beaker and keep the hydrometer from rolling away. So, as I mentioned, you can see that the hydrometer basically sinks all the way to the bottom of the liquid with the calibration reading almost exactly 1.00. However, if you take the same water, add a little bit of sugar, mix it up a little bit, and add it to the same test beaker with the same hydrometer, you will notice that it floats slightly higher. So, usually, this is used with your wort, whether it is just a sugar and turbo yeast wash, or a whiskey wash. Once you drain that liquid off the grains you can get a sample, fill this test beaker, and use the hydrometer to determine how much alcohol by volume that wash will potentially yield (that is, assuming all the sugar is fermented).
Thanks for tuning in, and we’ll see you next time!