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Tools of the Trade:
A Word About Hydrometers

An excerpt from "How To Brew Your First Beer, Rev. D.2" by John J. Palmer

DECEMBER 30, 2000

A hydrometer measures the relative specific gravity between pure water and water with sugar dissolved in it. The hydrometer is used to gauge fermentation by measuring one aspect of it, attenuation. Attenuation is the conversion of sugar to ethanol by the yeast. Water has a specific gravity of 1.000. Beers typically have a final gravity between 1.015 and 1.005. Champagnes and meads can have gravities less than 1.000, because of the large percentage of ethyl alcohol, which is less than 1. By the way, hydrometer readings are standardized to 59F, since liquid gravity (density) is dependent on temperature.

Temperature correction tables are usually sold with a hydrometer or are available from Chemistry Handbooks (ex. CRCs). Here is a short table of corrections:

50F => -.0006
55F => -.0003
59F => 0
65F => +.0006
70F => +.0012
75F => +.0018
80F => +.0026
85F => +.0033


A hydrometer is a useful tool in the hands of an experienced brewer who knows what he wants to measure. Various books or recipes may give Original and/or Final Gravities (OG and FG) of a beer to assist the brewer in the evaluation of his success. For an average beer yeast, a rule of thumb is that the FG should be about one forth of the OG. For example, a common beer OG of 1.040 should finish about 1.010 (or lower). A couple points either way is typical scatter.

It needs to be emphasized that the stated FG of a recipe is not the goal. The goal is to make a good tasting beer. The hydrometer should be regarded as only one tool available to the brewer as a means to gauge the fermentation progress. The brewer should only be concerned about a high hydrometer reading when primary fermentation has apparently ended and the reading is about one half of the OG, instead of the nominal one forth. Incidentally, if this situation occurs, two remedies are possible. The first is to agitate or swirl the fermenter to rouse the yeastbed from the bottom. The fermenter should remain closed with no aeration. The goal is to re-suspend the yeast so they can get back to work. The alternative is to pitch some fresh yeast.

Hydrometers are necessary when making beer from scratch (all-grain brewing) or when designing recipes. But the first-time brewer using known quantities of extracts simply does not need one.
Some HBA Recommendations: Click on item to order!

Bit o' the Brogue Scotch Ale: Chewy, slightly smoky example of Scottish Export Ale. A wee tad hoppier and maltier than a Scottish Light or Heavy. Similar in flavor to its English cousins, the Bitter family. Addition of peated malt enhances smoky character of this "session beer."

Willamette Valley Golden Ale: Golden ale with a clean crisp hoppy bite. Light to medium bodied with a nice white head. The origin of the hops used in the recipe are what gives it its name.

Burton Pale Ale: Example of a English Pale Ale. The use of Carapils and Crystal 120L give this beer a nice medium body as well as a pale to copper color. Kent Goldings provide a crisp bitter bite along the upper end of the bittering scale for this style.

Kulmbach Schwarzbier: Black beer with a rich, smooth and malty flavor...offset with medium hop bitterness and aroma, this is a tasty example of this commercially rare beer.

What in the Helles Bock: Pale version of the strong, dark, malty bock beer. It has a medium to full body and a high warming alcohol content. Perfect for those who like a higher alcohol content and pale color.

John Bull Malts: Syrup extracts are the canned soup of the brewing world. you can make a very good end product with minimal effort if you follow these simple instructions: (1) Do not follow the instructions on the can! (2) Always use malt extract to raise alcohol (syrup or dried), (3) Use sugar (corn or other) for priming only. When sugar is used as a fermentable it will develop a winery, cidery taste. (4) Always boil the wort (unfermented beer) for at least 15 minutes. This will help to clarify your beer and eliminate bacteria.

Party Pig 4.5 Gal. System: Party Pig 4.5 Gallon System includes all you need to get started kegging your beer in 2 of these 2.25 gallon PET kegs. When you're tired of bottling and just don't have the room for a full-size kegging system this set-up gives you another option. Includes: Party Pig Kits (2), Party Pig Activation Pump (1)

Click Here for a complete list of Wine Ingredient Kits Available at HBA

Bergamais (Beaujolais)

Perfect in time for the Beaujolais season or the fall holidays. Does not require long aging (average 4-8 weeks).
Chablis

Crisp, semi-dry white wine that may be enjoyed soon after bottling.
Red Burgundy

Well rounded and robust, the Burgundy can be cosumed young but ages very well also.

Click here for other great wine products!