# Questions tagged [specific-gravity]

Specific gravity in brewing is the ratio of the density of the wort to that of water.

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### [WIKI] How Do You Calculate Original Gravity?

This is a community wiki post. Anybody with more than 100 reputation can edit it. You may also post your own answer. I get no reputation if you vote the question up or down, however, please vote up if ...
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### Can we estimate the temperature rise in the primary due to fermentation?

OK, this is sort of cheating but I really liked this question so I thought I'd ask the question again in a slightly different way and try and answer it. I was wondering if we can actually estimate ...
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### Didn't hit gravity--how to calculate how much malt extract to add to the fermenter?

Lets say you were aiming for 1.047 but only hit 1.032. In a 5 gallon batch, how much malt extract would you need to add to the fermenter to bring it up to the desired gravity?
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### Does suspended yeast contribute to high SG?

I've got a SMaSH beer (Baird Maris Otter and EKG) finishing in primary. It's been fermenting for just over a week. Starting Gravity was 1.046. I mashed at 154F for 60 minutes. Fermented with WY1335 ...
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### Diluting beer after 11 hours of fermentation. What to expect?

Ended up with too high gravity wort. Since I was not prepared for this I didn't have enough sterile water to dilute the wort. I ended up pitching the yeast anyway and adding sterile water at 11 hours ...
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### Water PH level and the effect on original gravity

What effect, if any, does the pH level of my water have on OG?
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### Gravity Measurement Tools

What tools for measuring specific gravity are available to the homebrewer? EG: refractometer, hydrometer. What scale do they measure? EG: Brix, plato Since there hasn't been much activity on the ...
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### Is Final Gravity a good indicator of sweetness?

This question is as simple as the title reads. In general, if I know the FG of any given beer, can that be a good indicator to me of how sweet that beer will taste? So the higher the FG, the sweeter ...
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### Refractometer - what exactly can it measure?

I am using a refractometer to determine gravities. I am aware of course that values measured need to be corrected depending on OG of the fermenting batch. What I don't know is, what kind of sugars am ...
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### Why did I miss my high target gravity? By quite a lot. Is it just my brewhouse efficiency?

I cooked up my first Double IPA recipe over the weekend but have seriously missed the mark with the target gravity. So much so it most definitely won't be a Double. Target O.G. = 1.085 Actual O.G. = ...
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### Why doesn't FG reach 1.000?

My second beer brew has pretty much finished its primary fermentation. It started at 1.044 and is currently at 1.014... I don't expect it will go much further. Having brewed numerous wines I ...
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### Can I measure specific gravity a day after sampling?

Often when I pour a sample to be measured, there is a good 1cm of head obscuring the SG value. It can stay around for quite some time. Can I leave it overnight in order to take the reading the next ...
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### Why shouldn't we just use scales?

New on homebrew.SE, great forum here. Just a quick question - why shouldn't we just use weight scales to determine the OG and FG? My Hydrometer has broken and I can't be stuffed really buying a new ...
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### How do I predict final gravity?

I've been taking the original gravity and multiplying the apparent attenuation of the yeast. For instance: 1.040 OG x 75% apparent attenuation = 1.010 expected FG But I never seem to get there. My ...
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### What causes Original Gravity to be lower than it should be?

I am an extract brewer and every brew I have done the OG was lower than the intended OG, (my OG is always lower than the recipe's OG). For example I brewed the stout recipe below from beertools.com ...
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### How to know if kombucha is alcoholic?

So I am into making kombucha at home: I made a SCOBY, grew it, and I have successful kombuchas. My normal recipe makes a "ginger kombucha", pretty much kombucha with sugar and ginger. It disappears ...
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### Measuring the ABV of non beer/wine products

I sometimes make alcoholic ginger beer and alcoholic lemonade. How would one estimate the abv of something like that? Is it even possible?
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### Determining the right gravity after mash in all grain brewing

Say I am brewing a beer that is supposed to have an OG of 1.050. I'm doing all-grain brewing and at the end of my mash & sparge, if I took the gravity at that point, what should I expect? I ...
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### Does wood affect final gravity readings?

For beer aged either in oak barrels or on oak chips/cubes, does the contact with the oak noticeably affect final gravity, and if so, what is the direct cause?
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### Why measure gravities?

I've brewed a good dozen batches of beer from kits, extract, extract+grain, and now all-grain, and I've never measured gravities. Why measure gravity, besides to know what you're getting? Is there any ...
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### How to lower Final Gravity?

I made a Thomas Coopers Stout with 1.1kg of dark malt extract and 400g of maltodextrin and used the yeast that came with it. I got a Starting Gravity of 1.046 and Final Gravity of 1.024. Are there ...
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### Safe to return sampled wort to the primary after sampling?

I made my second batch of beer (ever) last Friday night, and in a few days' time I'd like to sample a bit of it so that I can check its gravity. Provided that I sanitize all of my equipment (siphon, ...
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### Measuring Gravity

What is the usual procedure for measuring gravity? Is it typical to just take an original and final gravity measurement or should measurements be taken throughout? I've heard people talk about ...
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### Why is it necessary to approximate starting and finishing gravity?

In the book "Home Beermaking", by William Moore, it talks about calculating starting and finishing gravity in chapter 6. I believe that he's talking about when I get good enough at homebrewing to make ...
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### what could be going on? 1065 to 1010 in 3 days and a half

This is just my first batch so I'm a complete newbie. I'm brewing a dry euro brown ale (grain + multiextract) and the temperature is between 57-67 f, but my bucket doesn't have a thermometer but I ...
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### Temperature correction for specific gravity

If I want to convert my specific gravity reading from one temperature to an equivalent specific gravity at 60F how do I do it? Can you give me a correction factor for this case?
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### How do you calculate how much extract to add if you don't hit your target gravity pre-boil?

Planning to do my first all-grain BIAB. If miss my target gravity after mashing, how do I figure out how much extract to add before I start the boil in order to reach that OG? I would imagine pre-...
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### Why would OG be significantly higher than predicted?

I know there are several questions on the forum about OG being lower than predicted. Please bear with me though. I'm at a loss. I just brewed a straightforward extract wheat beer recipe. The ...
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### ABV from one SG?

The most common way to calculate ABV (Alcohol By Volume) is through some correlation between Original Gravity (OG) and Final Gravity(FG). Is there any way to calculate ABV just from the current ...
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### Can I fix a higher than anticipated OG after primary?

I just brewed a witbier that was way below the estimated preboil gravity of 1.49. I only got 1.34 in case you're wondering. I've never had that bad of an efficiency before. The grains came ...
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### Sugar in water effect on specific gravity?

Is there an equation or relation to describe how much sugar is to be added to water to obtain a liquid with a specific gravity? In This question, for example, it is mentioned that "1 lb in 1 gallon ...
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### Does white honey have greater effect on gravity?

A few weeks ago I made my first mead (actually a braggot). I ordered a 12 lb bucket of raw honey. To my surprise, when I opened it the honey inside was a creamy, almost foamy opaque white. It didn't ...
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### My cider stopped fermenting until I swished it around in the bucket a bunch, then continued. Is that normal?

My malted cider had been brewing after about a week in my plastic brewing bucket to the point where the little 'hat' thing in my airlock fell onto the 'neck' (no internal pressure). I opened it up ...
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### Calculating sugar in fresh fruit

Recently I made a belgian strong ale. In the secondary I added 7 pounds of fresh cherries that were pitted, frozen, thawed, and blended up. Is there a good way to at least estimate the additional ...
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### How to calculate ABV% with step feeding

I would like to make a high ABV mead, and plan to divide the honey into 3 or 4 increments for the yeast. This has to be done so that the yeast are not under stress from osmotic pressure. However, I ...
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### IPA: When to Bottle

My IPA was in the primary for 10 days and gravity readings where steady before racking to the secondary. It’s been in the secondary for 13 days now and emits one bubble every 75 seconds on average. ...
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### Campden Tablets to Control Final Sugar Content

I've used Campden tablets per a recipe for cider to prepare the unpasteurized cider before pitching yeast, but recently came across the following in Wikipedia: Campden tablets are also used towards ...
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### Brewed an Oatmeal Stout and the gravity did not drop as much as predicted, should I re-pitch or add yeast nutrients/energizer?

I just brewed an oatmeal stout see recipe details here and I have a question about missing Orignal and/or Final gravities. The OG was supposed to be 1.061 and the FG 1.016. I brewed and got an OG or ...
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### checking gravity during and after fermentation?

How could I pull out a little from my carboy to take gravity readings during fermentation? I tried to use a auto-siphon but it was a mess.
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### How long can I let an IPA fermented while dry hopping?

The hydrometer reading is 1.014 from 1.058. I just dry hopped. How long should I let it ferment? Can I let alone for one more week without messing it up?
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### Is SG 1.005 OK for cider before first racking

The primary fermentation for cider is going for 9 days and SG wend down from 1.052 to 1.005. Is it normal to have such a low value before first racking? Should I add sugar to rise SG to 1.015 and ...
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### Correct temperature effect on Specific gravity

Is there an equation that corrects specific gravity while considering temperature effect in Celsius, which does not presupposes a set hydrometer calibration temperature? A direct relation, not tables ...
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### Does a malt "late addition" affect OG?

I'm following a recipe from a book for an IPA that calls for the following (simplified) steps: Boil water (3G/11L) Add Light DME (1lb/450g) & return to boil Add hops At 45 mins, add LME (6.6lb/...
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### Does any "probe" exist which can detect the gravity of wort?

I use a Raspberry Pi in combination with a temperature probe to measure the temperature of my wort. It would be nice if I had another probe that could measure the current gravity of my beer, so that ...
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### What gravity is suitable for not using priming sugar?

Assuming full attenuation, is there a way to figure out what gravity reading would be suitable to not use priming sugar, and just allow the excess sugar to create the carbonation? A sub-question would ...
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### How to approximate when half the sugar has been fermented

The EC-1118 datasheet suggests a procedure wherein you pitch the full amount of yeast in 10% of the total volume of your liquid, and let it ferment until approximately half the sugar is used up, and ...
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### Large drop in specific gravity over 24 hour period

My cider brew (5 gal) has experienced a large drop in its specific gravity readings over a 24 hour period. Yesterday it was measured at 1.05 with the kit recommending bottling at 1.04 or lower. Today ...
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### Activity in fermenter has increased suddenly after 2 weeks, why?

I'm a total beginner and really appreciative of any advice here. I'm making a 1 gallon batch of IPA from a kit. I brewed 16 days ago, and in the first 48 hours of the wort being in the fermenter it ...
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### Hydrometer correction equation

Can you identify the constants in your hydrometer correction equation? I know that 2.6X10-6 is the coefficient of thermal expansion for the hydrometer glass; what are the others (not related to ...
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