Specific Gravity Temperature Correction Calculator

All hydrometers are calibrated to be accurate at a given temperature. Most newer hydrometers are calibrated for 68 degrees (F). Because the density of fluids changes as their temperature changes if you don’t measure your specific gravity at your hydrometers calibration temperature you’re going to get an inaccurate reading.

Hydrometer calibration temperature printed on scale within the hydrometer.
Hydrometer calibration temperature as printed on my hydrometer.

While the correction may be small for a single reading if you don’t adjust, it becomes increasingly difficult to compare readings over time. For instance, if you take an original specific gravity reading at 75 degrees (F) and a final reading at 65 degrees (F) you can’t compare these readings because the fluid densities are different at the different temperatures. You must correct each of your readings for temperature differences before you can compare them. Continue reading “Specific Gravity Temperature Correction Calculator”

Wine Alcohol Content Calculator

Calculating the alcohol content of a wine that you made is always fun. While amateur wine makers don’t need to report this value to anyone it’s just neat to know how much alcohol you’ve produced.

Use Wine Equations and Calculators Only

A winery lab setup for determining alcohol content.
Winery determining alcohol content through distilling.

There are many formulas out there for calculating the percent alcohol of wine and beer. You may have noticed that they’re not the same. Largely this is because the relationship between the specific gravity and the amount of alcohol produced is not linear.

What this means is that specific gravity and alcohol content have a complex relationship that is not easily represented with a simple equation. Non-linear equations can be pretty nasty to deal with. Continue reading “Wine Alcohol Content Calculator”

Adding Potassium Metabisulfite to Wine

Potassium metabisulfite is a necessary preservative in wine making. It provides sulfur dioxide which helps prevent microbial spoilage and fight off oxygenation. However, figuring out how much to add can be complicated.

By the end of this article you’ll understand how this stuff works, how to calculate what you need to add, and what equipment you need to do it. Let’s get to it. Continue reading “Adding Potassium Metabisulfite to Wine”