Brewing beer has always had a connection with chemistry. So, some new to the art may feel surprised to hear a term associated with astronomy brought up in reference to beer. But in the brewing world, beer has nothing to do with the gravitational forces that govern orbit and the ocean tides. Even so, it’s implications on your final product are astronomical. That’s why these tips for hitting your target final gravity are essential for crafting the perfect brew.
What Is a Beer’s Gravity?
In this context, gravity is related to a liquid’s solubility. It is the amount of solid materials (in this case, sugar) that have dissolved in a liquid. The gravity of a beer may range from 1.000 to 1.020. The lower end of the spectrum includes dry wines and meads, while the higher end may include ale or imperial stouts.
The biggest implication of this is your beer’s fermentability. The more sugars in your beer, the more alcoholic it will be. Along with this, it may also impact a beer’s carbonation, body, flavor, and color. Given how much of a beer’s identity is tied to this number, hitting your target final gravity is crucial.
Tips for Hitting Your Target Final Gravity
Typically, when brewers have trouble with gravity, the issue is that their final gravity level is below their target gravity. With this in mind, these tips are meant to get your gravity count back on track.
Mind Mash Efficiency
One of the greatest factors impacting final gravity is the efficiency of one’s mash. Mash efficiency refers to how well one can pull sugars from the grain. If mash efficiency is low, then the final gravity will likely be too. Factors that impact your brew’s mash efficiency include:
- Grain crushing strategies
- Mash Time
- PH levels
- Adding too much sparge water
If your brewery is not already milling its own grain, consider milling it yourself to ensure that you are getting the best crush for your grains. Also, if the PH level is above 5.4, utilize lactic acid, calcium sulfate, or gypsum to lower levels. Even simply mashing longer can help improve mash efficiency.
Monitor Gravity Throughout the Process
A beer’s gravity will change before and after fermentation. Part of the reason for this is the fluctuations in volume due to boiloff rate, the size and shape of your stainless steel brewing equipment, and other factors. As a brewer, it’s important to keep track of both your original gravity and the typical boiloff rate of your brewing process. This way, you will be able to accurately and consistently predict your final gravity and be able to supplement sugar levels if needed.