Hydrometers. A short guide.
The humble Hydrometer. Every homebrewer has one and every homebrewer at some point has probably looked at their hydrometer and thought “how the f#%k do I read this thing?”. Yeah, us too, but hopefully this guide will help with anyone struggling with this ridiculously breakable brewing tool.
What does a hydrometer do?
A hydrometer reads the density of a liquid based on its buoyancy. For brewers it is measuring the concentration of sugar in a liquid.
How do we read this bad bouy?
A sample of wort to be tested is poured into a sufficiently tall container. The hydrometer is lowered into the liquid until it floats. Then we give it a little spin for fun and to get rid of any bubbles in the tube. The point where the liquid touches the scale on the stem is noted. This is your gravity reading.
When do I take a reading?
The first reading you should take of your beer is the Original Gravity (OG). For extract brewers this is when the beer extract and the sugar pack have been dissolved and the fermenter is topped up with water to the correct level. For the grain brewers this is after the boil, whirlpool/hop stand (if doing one) and cooling, as you add the beer to the fermenter take your sample.
Our second reading is the Final Gravity. This is the reading after our wort has fermented. This is also a great way to see if our brew has finished fermenting. If we take 2 readings 24hrs apart and they are the same, then our brew has finished fermenting.
How do I Figure out the ABV in my beer with my Hydrometer?
It’s a simple maths equation. First, we take the Original Gravity & minus the Final Gravity, then times this by 131 which gives us our % ABV.
(Original Gravity – Final Gravity) x 131 = % ABV
Example
1.056-1.010=0.046 x 131=6.026
Or if you are mathematically challenged like us you can use the tools found on the Brewers Friend website. (https://www.brewersfriend.com/abv-calculator/). Or most brewing apps will have this tool to help with the process.
If you have any other questions or need some help, please feel free to stop in at 51 Main Rd, Moonah or
call us on (03) 6278 3881.
