Newbie Q's. Fermentation time & Evaporation

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ScoobyDude

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I have two unrelated questions here:

1. How long does my beer need to ferment/sit in the primary carboy (not using a secondary) prior to bottling? or maybe a better question is when do I know it's done? And adding to that, what factors contribute to fermentation time?

2. When preparing the wort, how much loss occurs due to evaporation? My 5 gallon batch came out looking pretty short. I'll admit I did not measure out the gallon line in the 6.5g carboy, so it may well be fine, but I am still curious if evaporation is significant since the liquid is boiling for 90 minutes or so.
 
I may know the answer to my first question, which is the to get a final gravity reading at 1.000.....but again, unsure of this, and do not know if this holds true for all beer varieties.
 
I have two unrelated questions here:

1. How long does my beer need to ferment/sit in the primary carboy (not using a secondary) prior to bottling? or maybe a better question is when do I know it's done? And adding to that, what factors contribute to fermentation time?

I typically leave it in primary for three weeks and then keg it. I take a FG sample only so I know what the ABV is. Since you're bottling and have to worry about bottle bombs, wait 3 weeks and then measure the gravity. Wait 3 days and measure it again. If it hasn't changed, it's safe to bottle.

2. When preparing the wort, how much loss occurs due to evaporation? My 5 gallon batch came out looking pretty short. I'll admit I did not measure out the gallon line in the 6.5g carboy, so it may well be fine, but I am still curious if evaporation is significant since the liquid is boiling for 90 minutes or so.

Evaporation rates vary significantly by surface area of the wort, humidity, altitude, and how high you turn your burner up.

I boil off about 1.8 gallons per hour with my setup. Yours may be more or less.
 
ScoobyDude said:
I may know the answer to my first question, which is the to get a final gravity reading at 1.000.....but again, unsure of this, and do not know if this holds true for all beer varieties.

You won't get that low with most non-infected beers. Rather, you want a stable FG over a couple days. I keg most beers after 10-14 days in primary; nearly all are finished after 4-5 days.
 
Normal beer typically finishes in the 1.008 to 1.020 range. Never saw one any lower than 1.008.
 
You know that the beer is done when two gravity readings, done three days apart, read the same level and the gravity is within "range" for the recipe you are brewing. A big Russian Imperial Stout can be done when the gravity is around 1.030 but a lighter style of beer (pale ale, saison, etc.) won't be anywhere near done at that point. You want to be within a point or two of the recipes final gravity.

Evaporation is equipment related. You should do a test with your equipment just boiling water in the same pot, same starting volume and same burner as you use when making beer. After an hour (or 90 minutes if you tend to do longer boils,) shut the burner off and cool the water to normal pitching temp. Then measure what you have left to figure out what your evaporation rate is.
 
I have two unrelated questions here:

1. How long does my beer need to ferment/sit in the primary carboy (not using a secondary) prior to bottling? or maybe a better question is when do I know it's done? And adding to that, what factors contribute to fermentation time?

Until it is done. When the FG has been stable for a few days (some people recommend to check it once a day for 3 days, but I use the method of check it once and then check again 2-3 days later). If it stays the same it is either done or stalled (search the forums about stalled fermenations). Amount of fermentable sugars, temp, and yeast used are probably the primary factors but might be others.

2. When preparing the wort, how much loss occurs due to evaporation? My 5 gallon batch came out looking pretty short. I'll admit I did not measure out the gallon line in the 6.5g carboy, so it may well be fine, but I am still curious if evaporation is significant since the liquid is boiling for 90 minutes or so.

As LovesIPA stated there are many factors that will effect teh rate at which your wort will evaporate so giving you a definite answer would be next to impossible, but I believe mine is around 1.65-1.9 gal per hour.


See my answers in red.
 
As said earlier, the best solution is to run a test boil with water and measure out the results of boiling for at least an hour, preferably 90 minutes or more, and measure the result after it is cool. You should be able to calculate the boil-off rate by dividing the difference in the wort by the time in hours.

Once you know the boil-off rate, you should be able to adjust the amount of starting water to compensate for the boil-off. Alternately, you can simply top off the wort with an amount of prepared water after the fact, but it is generally better to boil the full wort if you can.

It perhaps should be noted that evaporation is a deliberate and necessary part of all-grain brewing, at least as most brewers do it; after sparging (rinsing) the sugar out of the malt, you end up with a very thin wort, with the final runnings generally being down to 1.010 or less. You need to boil it down to reach the desired original gravity. Depending on the amount of water used, and the boil-off rate of the burners, this can take anywhere from an hour to up to four hours with a very low-BTU burner (like mine :(). It is generally possible to calculate ahead of time how long it will take to boil off the water, and adjust it to be a specific time, if you know the boil-off rate for your equipment. Thus, if you plan on going to all-grain, knowing the boil-off time for a given configuration is crucial.
 
For your average alcohol beer, you are looking at 1-2 weeks. You can also take gravity readings, when it stops dropping you are done.

You will lose a significant amount of beer to evaporation, how big that number is depends on a lot of things, but you should plan for at least a gallon disappearing.
 
1. After 2 weeks in the fermenter take 1 gravity reading per day for 3 days. If it's the same all 3 days, then you're done. If you used extract, it should be very close to the expected FG. If you did AG, your FG could be way off or spot on depending on what kind of efficiency you got.

2. Note that a vigorous, rolling boil is NOT required for brewing beer. I keep a controlled, slow boil for 60-90 minutes (depending on my initial volumes) and this significantly lowers my evaporation rate. The goal is to boil the wort for optimum hop utilization and general sterilization. Neither require the wort to be going apesh*t for the duration. An added bonus is that a slow boil makes it easier to control the foam especially with the hop additions.
 
Solid advice posted on here, so I won't repost what others have said.

I do want to add though, as a beginner, don't rush your beer. Weather you think it's done or not, just let it sit in primary for at least two weeks. This will allow the yeast to settle out a little bit more, giving you a cleaner tasting end product.

There are a lot of mistakes a first time brewer will make. Some of these mistakes can be cured with a little time and not rushing things. One of the big things is keeping your fermentation temps in the lower end of the suggested range. Room temp does not equal the actual temp the beer is fermenting at. It will be warmer and that will produce off flavors.

About the boil off, I'd be surprised if you weren't boiling off at least 1 gallon/hour. So if you are doing extract kits, make sure to mark your 5 gallon on your fermenter. This way you can top it up with enough previously boiled and cooled water to get you to 5 gallons. Extract kits are usually based on a 5 gallon model. So if you are a gallon or two short, you are going to end up with a more concentrated wort, which can lead to much higher alcohol content and also leaving you with a beer that's out of style of what you were hoping to brew.
 
Whattawort said:
The goal is to boil the wort for optimum hop utilization and general sterilization. Neither require the wort to be going apesh*t for the duration. An added bonus is that a slow boil makes it easier to control the foam especially with the hop additions.

Another reason for the boil is to drive off SMM, the precursor to DMS; this is done best with a vigorous boil (especially when using Pils malts).
 
Great. Thanks for all of the information. Just eye balling it, it did look about a gallon short. I was using an extract kit so I did top it off some to where I thought it should be. (I had transferred 5 gallons of sanitized water into it before hand, i just forgot to mark the 5g line, so I still had a rough estimate of where 5g should be). And maybe because it is short, my baster to collect the FG reading is just shy of hitting the beer and I haven't yet mastered the (non-auto) siphon, so may just let it sit to 3.5 weeks since brew day to rack it to my bottling bucket and hope the one and only FG reading is a stable one. I don't want to be lazy about it, but i was struggling with getting a siphon going when practicing that before my initial wort transfer (ended up just using a funnel).....in the future I think I'll use a carboy cap to manage that action better.

Thanks again. Great advice.:mug:
 
ScoobyDude said:
Great. Thanks for all of the information. Just eye balling it, it did look about a gallon short. I was using an extract kit so I did top it off some to where I thought it should be. (I had transferred 5 gallons of sanitized water into it before hand, i just forgot to mark the 5g line, so I still had a rough estimate of where 5g should be). And maybe because it is short, my baster to collect the FG reading is just shy of hitting the beer and I haven't yet mastered the (non-auto) siphon, so may just let it sit to 3.5 weeks since brew day to rack it to my bottling bucket and hope the one and only FG reading is a stable one. I don't want to be lazy about it, but i was struggling with getting a siphon going when practicing that before my initial wort transfer (ended up just using a funnel).....in the future I think I'll use a carboy cap to manage that action better. Thanks again. Great advice.:mug:

Do yourself a favor and go to your LHBS and get an auto-siphon. $10-15 well spent not risking contaminating your beer doing an old school siphon.
 
I just shoved my turkey baster into the end of the tube to get the siphon going (Ididn't feeling like using the auto siphon just to get a small sample), but you really should get an auto spiphon when you get read to transfr it to the bottling bucket.
 
Start with 3 gallons and you'll finish with roughly 2.5 gallons. Do it the same way when you boil your wort AND when you boil your top off water and you will be fairly close to your 5-gallon target.
 
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