Flotation Hydrometer

We have an electronic hydrometer to measure the ABV of spirits, but at home all you need is a flotation hydrometer, which costs less than £10 (US$12) (versus electronic ones at £340/US$438). Flotation hydrometers are really easy to use, simply pour the liquid into a test tube, insert its float and wherever it comes to rest is where you measure the ABV. Their downside is that they’re not hugely accurate, as your room needs to be at 20–21°C (68–70°F). Any hotter, and the reading won’t be precise. We distill our own spirits, so it’s vital we know the precise ABV, but unless you’re distilling at home, and stopping before all the water has distilled, you’re likely to be producing spirits at around 40%, so a flotation hydrometer will be accurate enough.