# Tag Info

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This is a community wiki post. Anyone with more than 100 reputation may improve it. I get no reputation points for votes. Background Definition Specific gravity (SG) is a measure of density. By convention, pure water has a SG of 1.000. Substances denser than water have a higher specific gravity. For example, if a beer has an OG of 1.050, it is 5% heavier ...

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In order to be able to calculate fermentation temperature, an exothermic process, we need to know how much heat (H) is "evolved" as yeasts convert sugars to alcohol. Digging around in the literature I found this article (1). Although its focus is bioethanol production, it does give some figures in terms of joules per mole which we can use to do the ...

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If you know the gravity and physical weight of the beer, then you can work out the quantity (volume) like this: V = W / SG where V is the volume in liters W is the weight of the beer in kilos SG is the specific gravity, e.g. 1.040 For this to be accurate, you have to be weighing just beer - the trub and yeast should not be present. To convert to ...

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The starting gravity and ending gravity serve many purposes, but ultimately will only tell you one thing, the percentage of alcohol. Some of the purposes it may serve are: Beer style guidelines Mouthfeel, flavor, bitterness, even aroma (FG) Yeast tolerance (SG) Efficiency of sugar extraction in all-grain brewing (pre-boil gravity) Hop efficiency How much ...

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There is brauhaus - a javascript library for homebrew beer calculations, both in the browser and on the server I have not used it - the homepage says features include: Support for multiple Javascript runtimes Node.js 0.6.x, 0.8.x, 0.10.x Chrome, Firefox, Internet Explorer 9+, Safari, Opera, etc Calculate estimated OG, FG, IBU, ABV, SRM color, ...

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This seems like a simple solution dilution problem. Take 5 gallons = 20 quarts => 20 quarts * 5% ABV = 1 quart alcohol. Then take your 1 quart of "80 proof" (40% ABV), and we get 1 quart * 0.4 = 0.4 quarts alcohol So we have a total volume of 21 quarts (beer plus spirits) and a total of 1.4 quarts alcohol, thus 1.4 / 21 = 6.67% ABV Unless I'm ...

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Hopville has a nice online recipe calculator: http://beercalculus.hopville.com/recipe. You can store your recipes on the site too which makes it very easy share your awesome creations with others :)

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BeerSmith is an excellent brewing software. It offers easy to understand recipe creation and a brewday instruction sheet. It also allows for different equipment setups. Recipes generally follow style guidelines.

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Take a look at BrewBlogger. According to developer: BrewBlogger is a web-based alternative to software such as BeerSmith, ProMash, and others. I'm busy giving BrewBlogger a try now and I'm pretty impressed. In the commercial space, BeerSmith is quite popular as is ProMash. There are quite a few available in the open source space but the only ...

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BeerCalculus is really nice to put your recipes together. Since it's a web app, it's platform agnostic. I don't believe it does anything like inventory management. I've used BeerSmith in the past, and it's really nice and worth the money if you need inventory management.

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What you're not accounting for is the CO2 produced during fermentation. The colder the beer ferments, the more CO2 will be in solution in it. That kinda gives you a "head start" on carbonation. If you don't account for the CO2 retained, your beer can be either over or under carbonated.

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Beersmith currently allows for late addition of extract. And it allows you to enter the time at which you are entering it. Promash is popular, but worthless when it comes to updates. Beersmith is supposed to be coming out with an update later in the summer, just something to keep in mind if you chose to buy a copy.

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All temperatures are in expressed in degrees F. correction = 1.313454 - 0.132674*F + 0.002057793*F*F - 0.000002627634*F*F*F SG_corrected = SG + (correction * 0.001) http://www.primetab.com/formulas.html agrees with http://brewery.org/library/HydromCorr0992.html

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If the starter fully fermented, most of the 1.040 should be gone; normal yeast attenuation is around 75%, so you should have 1L of 1.010 beer in the starter vessel. 1L of 1.010 beer into 19L of 1.076 OG wort would reduce the OG down to about 1.073. (76 points * 19L + 10 points * 1L) / 20L = 72.7 points = 1.073. Though if possible, you should try to cold-...

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Unfortunately, there currently is no scale to quantify and measure the amount of hop flavor and aroma in beer. Essential hop oils in beer provide this hoppy flavor and aroma, so you might think that if the amount of essential hop oil in beer could be accurately measured, then such a scale for non-bitter hop quantity would exist. However, chemists have not ...

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I went to the thread and the chart is there. Are you referring to a different chart? If you make 5 gallon batches typically under 1.060 OG you mash tun only needs to be a little over 4.5 gallons in size. I got to this figure assuming 12lbs 2-row at 70% efficiency to get 6 gallons of 1.060 wort (preboil). If you then assume that you may on occasion want ...

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Here is a link to a NB document that outlines how to use one and two stage yeast starter. There are some lengthy equations that can easily be entered into a spreadsheet for easy calculation. It will also give you the different rates when using a stir plate.

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I can't say enough about BrewPal! iPhone app (which is great because I don't brew in front of my computer). Only \$0.99! Built in mash (fly, batch, decoction, partial, or steep) and boil timers (so I can enjoy as many homebrews as I want and not forget to add the 15 min hops, irish moss, or wort chiller...). I'm a developer and was going to write my own ...

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I use BeerAlchemy (Mac/iPhone only), and it does pretty much anything I need, including keeping track of inventory. The iPhone version is really neat, and syncs to the Mac-version. The only thing I miss is listing batches by date, I use a spreadsheet on Google Docs for that.

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There is an efficiency difference - while a lot of the starch in caramel malts have been converted, there is still some remaining that can be extracted in a mash, but not in a steep. Also, the mash is typically done for longer than a steep, plus a sparge, which extracts more sugars from the grain. 30% extraction for a steep seems on the low side - but let's ...

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Your general understanding is pretty much spot-on. I think the thing to consider here is that your reasoning assumes that half or a third of the priming sugar is meant to yield the same amount of carbonation as it would in the bottle. I'd argue this isn't the case. Notice how recommendations like this keg-underpriming 'common wisdom' usually don't go so far ...

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You can calculate ABV using the below equation: ABV = (OG - FG) * 131 So, with the use of some Algebra, you can calculate FG using the below equation: FG = -1*(ABV/131 - OG)

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I too was curious about this the other day. Turns out for five gallons/18.9 L of 1.060 wort at 75% apparent attenuation, 449.1 L/ 15.86 cubic feet/ 118.64 gal of CO2 is produced (standard temperature and pressure. This amounts to 0.88 kg/ 1.94 lb of CO2! I have a few charts for different gravities and apparent attenuations at my blog post about it. I ...

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There was a discussion on HBT about this. If you measure in Fahrenheit, the formula is as follows: C = ((1.313454 - (0.132674*F) + (0.00205779 * F^2) - (0.000002627634 * F^2))) Where C is the correction, and F is degrees Fahrenheit of the liquid being measured with the hydrometer. This assumes the hydrometer is calibrated for 59 degrees Fahrenheit. ...

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The easiest way to determine the effect of starter gravity is to decant the starter so the amount is negligible. In addition, I've found that it makes better beer.

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I don't think you can calculate this number. They report a max extract using a standardized lab test obviously. But then the rest is subject to too many variables for there actually be something to calculate. Its system and brewer dependent on what the ppg will be. I think your calcs are spot on as far as getting in the ball park. Maybe assume a 5-8% ...

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Open-source brewing software: brew-journal: http://github.com/jsled/brew-journal (disclosure: my project :) docstring comments in the computational classes in app/models.py have links to references). qbrew: http://www.usermode.org/code.html brewtarget: http://brewtarget.sourceforge.net/ Non-open-source brewing software: Brewer's Friend has a number of ...

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I have used BeerTools Pro quite successfully on Windows. They have a free web-based version on their site as well, but it limits the number of ingredients you can add and lacks the mash schedule calculator which I used quite a lot. I stopped using it so much when I moved from a Windows laptop to an Ubuntu laptop and found that BeerTools doesn't run under ...

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"Beer Calculus" is great. http://beercalculus.hopville.com/recipe This calculator has an EXTENSIVE selection of malt/fermentation (preloaded OG/FG and color based on sugars), hops (with typical AA %), yeast strains (ale/lager, dry/liquid, and flocculation level), and boils/primary/secondary add-ins (lots of them!). Great calculator where you can select ...

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Assuming you are using his pitching rate calculator, here is what I would suggest: Switch it from "Simple Starter" to either "Simple Starter with O2 at Start" or "Simple Starter with Intermittent Shaking." O2 at Start basically means you shake it up really well when you start the fermentation of the starter (or if you add oxygen via diffusion stone). ...

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