Beer output less than expected

[jasonrhaas]

Hey guys,

I'm on my second brew now, and I've noticed that I'm not getting as much beer output as I would expect. The first batch was way less than 54 bottles, but I think that was because I lost a bunch in the transfer from the primary to secondary fermenter.

For the 2nd batch I just did last night, the instructions say to fill up my primary fermenter with wort + water until I hit 5 1/4 gallons. But a took a hydrometer reading at about 4.5 gallons and it was already at the expected specific gravity of 1.050. So right off the bat I'm producing less beer than I would like.

What should I do here? Just accept the lower beer output or water it down to meet 5 1/4 gallons?

 

[Biscuits]

Before making a decision, I suggest you stir the living crap out of the wort to make sure it is mixed well. A common mistake in new brewer, and some old, is that they get bad gravity readings because they don't mix well or they don't cool the wort to the appropriate temp. So, do those things first.

If you're still getting the same reading then in my opinion, I would leave it and accept that you'll have less beer. My reasoning for this is that I would rather have 30 bottles of good beer than 50 bottles of not-so-good beer.

If you're doing extract and followed the directions to the letter, I doubt that your gravity is that far off.

 

[ProblemChild]

If gravity is hit, bottle as is with a smaller batch. Let it be.

 

[TripleC223]

A lot can affect the volume of your final product. I'm assuming you set 54 bottles as your benchmark because 5 gallons = 640 ounces, and 640 should equate to 53.3 12-ounce bottles.

However, it's common (and honestly, should be expected) that you will lose some of that wort/beer during various steps of the homebrew process. When you transfer from the kettle to the fermenter, then the fermenter to the bottling bucket, and finally from the bottling bucket to the bottles/keg, you will lose a small bit of beer each time in the form of the gunk left at the bottom, or what your siphon doesn't pick up. If you rack to a secondary fermenter, you will lose a little bit more at that stage.

Don't forget to discount the wort/beer you collect when sampling gravity as well. Two or three gravity samples can equal one or more bottles of beer.

Also, hops and fruit absorb beer, so the more of of those you use during fermentation, the less final product you will have. In my experience, I typically end up with more bottles of a less-hopped beer (think hefeweizen) than I would a heavily hopped beer (IPA).

Also to echo the points above, it's hard to get an accurate original gravity when brewing extract, especially if you're using top-off water. You really have to stir and shake the hell out of the wort to truly mix up everything proportionally. I honestly don't even take an OG measure anymore and just trust my recipe calculations. By the time you take your FG though, everything will have balanced out, so you should trust those numbers as more reliable.

I would consider getting 4.5 gallons from a 5-gallon batch into a bottling bucket a decent yield. That's a loss of around 5-6 beers, which is about right, especially if you've already transferred to a secondary fermenter.

Bottom line, for a five-gallon batch, I have come to expect 45 bottles as my normal yield. And as stated, I'd rather have 30 bottles of good beer than 50 bottles of watered-down beer.

 

[jasonrhaas]

Thanks for the responses. I'm pretty sure I stirred up the wort pretty well before taking the gravity reading, but it may have settled out too much before I got everything (I'm using a small wine thief). I went ahead and added some more water anyway assuming I must have done something wrong. I still have maybe .5 gallons less than the recipe called for, but I'm hoping it will turn out ok in the end.

 

[ProblemChild]

I would highly recommend measuring volume after Lauter.

I would also get a refractometer and take pre-boil readings.

As a caveat, I would recommend NOT measuring the gravity of the wort until you have stirred it really well before boiling if you choose to measure before boiling. I don't

My own preference is to give a single, decent stir of the wort a few degrees before boil, then remove a small sample with a ladle and chill it in a pyrex measuring cup (only to ensure that handling beyond that point is safe and for no other reason). I then take the refractometer reading. Consider that as your pre-boil gravity. Wort sitting in the kettle immediately after sparge is stratified and it is hard to get a proper reading. When the wort is near boil, the convection of heating has already stirred the pot a great deal and readings from my experience have been consistent.

Here is a great check to do in process. A little theory, but immensely valuable. Again - the caveat - do not be in a hurry to compensate until you know how well your process works.

This early check lets you know if you have an extraction/efficiency issue (not a lot of sugar being taken from the grain)

Do the basic calculation of volume x the last two digits of the gravity (if 1.050 SG, then use "50") to find the gravity units (GU).

So, if you were supposed to get 6.9 gallons pre-boil with a gravity of 1.050, the equation would be 6.9 x 50 = 345 GU

Say you only had a gravity reading of 1.045 at this point - that would be 6.9 x 45 = 310.5 GU

That is the real magic of mashing - how much sugar did you get. Should I have gotten more or did I hit it out of the park?

If you actually got a gravity of 1.055 and had the same 6.9 gallons, you would have 379.5 GU

In that case, you could figure 379.5 GU/50 =7.59 and you could add another .69 gallons to hit target gravity.

This is all mentioned for one simple reason - if you do not start with enough water or sugar, you will not finish with enough unless you learn how to properly add water or sugar.

 

[helibrewer]

You are doing extract brewing so mash and lautering efficiencies don't apply. Your recipe is designed to produce 5.25 gallons into the fermenter so if you lose more than 1 qt of product between fermentation and bottling, your yield will be down. A couple things might help:

Do you use whirlfloc or Irish Moss in the kettle?
This will help coagulate proteins so you can leave them behind in the kettle when transferring to your fermenter. The more trub in the fermenter, the more product loss.

Do you whirlpool post boil?
You can do this with a paddle, get the wort rotating at about 2m/s or so and stir for several minutes, then stop and let the wort settle for about 15 minutes. This should produce a trub cone in the center of your kettle which makes leaving it behind during transfer easier.

Don't secondary, it's not necessary (with a few exceptions) and just creates more loss.

Use a fermenter with enough headspace to not lose product through blow-off

Adjust your recipe to increase your post-boil volume to 5.5 or 6 gallons

Hope that helps...Cheers

 

[Timberline]

I'll tell you what NOT to do. Don't, on bottling day, say to yourself "dang my yield isn't what it should be but I've got what looks like it could be good beer left in the bottom of the bottling bucket on top of the yeast cake" and then bottle that. I did this on my recent IPA and got 4 extra bottles. Fortunately I had the presence of mind to put special marks on the caps of those bottles that I was trying to stretch. They were each quite nasty and were poured down the drain. The rest of the yield (~50 bottles or so) was quite good though. Lesson learned. As Heli said above, I've got to adjust my pre-boil volume to anticipate a better fermentation and bottling volume.