When is original gravity measured

This done, now the wort whose original gravity reading has been taken is then placed in the Fermenter Tank where it is fermented by the yeast. When the beer is ready, we need to take the Final Gravity reading with either of the instruments mentioned above.

The final reading would show us how dense the drink finally is after all the sugars have been fermented. Once the original and final gravity have been calculated, it is very simple to determine the Alcohol By Volume. The formula for ABV is:. The above is the universally accepted formula, but a more accurate one has come into popular usage for professional brewing:. So, if your OG is 1.

Created in a Scottish Brewery, this is quite literally a venom that can disarm you within seconds of intake. Appropriately named. To understand this concept, you need to keep in mind that temperature is a big factor which can change the readings of the gravities quite a bit. You should be relatively confident of your ABV before you market or even recommend your beer to a friend not just because of the market regulations, but to ensure that people remain aware of when and how to enjoy it.

When grains for the wort are added, the density increases. For example, a stout may have an SG reading of 1. SG will be used in the beginning and the end of the brewing process. You will have an 'original specific gravity' OG and a 'final specific gravity' FG. In the end, the difference between the two gives you the ABV. When buying grains or malt extracts for a beer recipe, you will need to know each grain's PPG rating points per pound per gallon. The supplier may have this information and there are online charts available for common grains.

Mash efficiency must also be factored in. In reality, the OG calculation looks like this because no homebrew operation is percent efficient most are in the 80 percent range. Homebrewers love abbreviations! The formula for estimating the alcohol by volume of a beer is easy when you have the two gravity numbers:.

These two numbers will remain consistent across all beer recipes:. Follow the instructions for your hydrometer or refractometer for this. Your final gravity FG , which is taken just before packaging and before you add any priming sugar. Again, make sure you have adjusted for temperature if necessary. So, if you have a beer that has an original gravity of 1.

This is the most practical way for the typical home brewer to estimate their ABV. Benjamin Stange is a freelance writer specializing in craft beer and home brewing. He lives in Springfield, Missouri with his family, who graciously tolerates his obsession with all things beer. I agree but you never gave us an idea of how far off it could typically be. Can you tie accuracy to brew styles like light, medium and dark brews? BTW, I never thought the amount of alcohol was that important anyway however I do understand it changes the taste.

It will rarely be off by a lot, and a hydrometer will serve for all practical purposes in the home brewing world. I tried dividing, I tried multiplying but neither resulted in 5. Why all the different formulas like I said, I am math stupid. Regarding the equation trouble, try This value is good, if not great; 30 ppg is basically what everyone shoots for.

I believe either can be used for OG but as far as efficiency is concerned I use my preboil wort to get that number. That's the best way to get a reading and efficiency with only the sugars from your grain being present. The reason you want to use pre-boil for the MLT efficiency is because after the boil, you've evaporated off some water and will have concentrated the wort.

This will raise the gravity of the wort. If you were to use the post-boil numbers, you'd get really good efficiencies, but they wouldn't be accurate as to what you are able to extract from the grains. Docjowles Well-Known Member. Yeah OG and pre-boil gravity are two different numbers and both are important.

Pre-boil is very good to know because it lets you know your efficiency, and whether or not you need to add extract or water to the wort in order to come out post-boil at your desired OG. Docjowles said:. RogueGoose85 Well-Known Member. Joined Sep 5, Messages 14 Reaction score 0. RogueGoose85 said:.

Tinhorn Well-Known Member. Any answer to this question? Very curious. This is still a little confusing when using the BeerSmith and ProMash refractometer tools. When entering the information into the refractometer tools is the OG number supposed to be from wort pre-boil or after boil? If I enter the pre-boil gravity reading I took with my hydrometer of 1.

But if I enter the post boil gravity reading I took with my hydrometer of 1. Then would that mean I couldn't trust any of the hydrometer readings.