The number one thing that we get asked about is how to hit specific gravity. Some brewers are still confused with changeable mash conversion results leading to lower levels of efficiency than they planned for. So here is our guide on how to combat this.
This technique is very commonly used in commercial brewing. Which is where we discovered it. Where ultimately a secure starting and final gravity are vital. This is because if the brewery says 6% ABV on the bottle it needs to be within this fine level of acceptance. This is how it works.
If you need more help in calculating your gravity check our Homebrewing 101: Hydrometer VS. Refractometer.
Firstly aim for 10% more gravity in your recipe compared to what you need. You can go higher than this if you feel you need to. Make sure to balance your hop bitterness at this higher level of alcohol to ensure you keep the balance of the beer consistent. Brew as normal until you’re almost at the end of the boil. Then you will need to take some measurements.
Specific Gravity/Liters
For this method, you will need to refractometer that shows specific gravity. Take a drop of wort and pop it into your refractometer. Let it cool for 5 minutes and take a reading. This becomes your current gravity figure.
Then measure how much wort you have. This becomes your current volume. You will also need to know what your target gravity is by referring to your original recipe before you added your 10%. When working with gravity figures just take the last digits of the reading.
Current volume multiplied by current gravity and divided by target gravity. The answer to this equation is defined as Liters of Wort. Then make a final calculation.
Liters of Wort is subtracted by the current volume equal dilution amount in liters.
It’s common to add cold water in aiding in colling quickly. This is also a great route to go if you are adding many additions and want to have a wider spectrum of flavor.
Plato/Barrels
Firstly you check your brewing system for how many barrels of wort you have multiplied to your current Plato. Divide this by your target Plato to reach a final sum for Barrels of Wort.
You then need to subtract Barrels of Wort from the current barrels of wort in your brewing system to reach your final dilution figure in Barrels.
After you have done these measurements based on the two above methods you will know how much additional water you need to add to your beer to increase the efficiency.
