Oxygen exposure when dry hopping a half-full fermenter

[luizffgarcia]

Guys,

I have a 1 gallon batch i want to dry hop, but the problem is i had too much water evaporation during the boil and i chose not to complete with water, so my 1 gallon fermenter is not full.

Since it is not full the surface which would be exposed to oxygen is larger than it should be for when i open the fermenter to throw the hops in. If the fermenter was full there would be almost no space for oxygen to get in, but right now there is plenty...

My question is, should i worry about this at all?

Thanks

 

[captwalt]

some folks would call that a half empty fermenter.
I wouldnt worry about it at all. dry hop away

 

[IslandLizard]

After fermentation that headspace is filled with a CO2/air mixture. Then just drop your pellets in there and put the airlock back on. It will be fine.

Now 2 quarts of beer is not a lot to drink...

 

[luizffgarcia]

Thanks for the help.

LOL, it has around 3 liters of beer on it, i have two 1 gallon fermenters and the other one is full, i am starting now so i like small batches in case i screw up

 

[IslandLizard]

Did you rack the beer from another fermentor into these 1 gallon fermentors? Them being your secondaries now?

 

[luizffgarcia]

Did you rack the beer from another fermentor into these 1 gallon fermentors? Them being your secondaries now?

No those are my primaries. Why do you ask? Does it make a difference?

 

[IslandLizard]

No those are my primaries. Why do you ask? Does it make a difference?

No not that much difference*, just wondered how one is full and the other 3/4 full. Full (primary) fermentors tend to blow a lot of beer off, that's why we want to have some headspace, around 1/5 - 1/4 of the total volume usually. In comparison, secondaries should be full, with very little headspace, like 1-2" in the narrow neck of a carboy, to prevent (unwanted) oxidation and possible infection.

Do these 2 fermentors contain beer from 2 different kits or recipes?

You mentioned you didn't top up your one recipe after boiling off too much water. That's a choice you made, and can be good or not so good. Realize you've got the ingredients for a 1 gallon recipe in a smaller volume (3 liters), and thus it's at higher gravity. Stronger beer but less of it.

*Generally, we don't need or even want to do secondaries. Leaving the beer in its first and only (primary) fermentor on the yeast for up to 6 weeks is fine or even preferred. Most new brewers following a kit's recipe to the T, fall victim to racking to a secondary after a few days to week or so because the kit tells them too. The trap is: a) it's too early, and b) unnecessary. Again, on homebrewers scale secondaries are seldom needed, and are an advanced technique that needs to be done correctly or it will give you problems, such as infection and oxidation.

 

[luizffgarcia]

No not that much difference*, just wondered how one is full and the other 3/4 full. Full (primary) fermentors tend to blow a lot of beer off, that's why we want to have some headspace, around 1/5 - 1/4 of the total volume usually. In comparison, secondaries should be full, with very little headspace, like 1-2" in the narrow neck of a carboy, to prevent (unwanted) oxidation and possible infection.

Do these 2 fermentors contain beer from 2 different kits or recipes?

You mentioned you didn't top up your one recipe after boiling off too much water. That's a choice you made, and can be good or not so good. Realize you've got the ingredients for a 1 gallon recipe in a smaller volume (3 liters), and thus it's at higher gravity. Stronger beer but less of it.

*Generally, we don't need or even want to do secondaries. Leaving the beer in its first and only (primary) fermentor on the yeast for up to 6 weeks is fine or even preferred. Most new brewers following a kit's recipe to the T, fall victim to racking to a secondary after a few days to week or so because the kit tells them too. The trap is: a) it's too early, and b) unnecessary. Again, on homebrewers scale secondaries are seldom needed, and are an advanced technique that needs to be done correctly or it will give you problems, such as infection and oxidation.

Yes the two gallons are two different recipes, variations of the same Ballast Point Sculpin recipe actually.

I have never tried moving to a secondary because i am afraid of oxygen exposure, i am still a newbie so i am taking one step at the time.

The bad thing about brewing 1 gallon recipes is i cannot afford to waste any of my precious beer to check the gravity, which leaves me a little lost as when to bottle.

I am planning on bottling after two weeks on the primary, some say its enough, some say it is not.. Any thoughts on that?

 

[IslandLizard]

Good call on not using secondaries, definitely with IPAs.

2 weeks should be enough, you got to eyeball it.

You could use a refractometer, only needs 1-2 drops. <$25 on eBay.
Once there is alcohol in the beer, you need to use a calculator, which requires you to type in your OG, so you have to get that before you pitch yeast. Very simple.

 

[ArthurDigbySellers]

Yes the two gallons are two different recipes, variations of the same Ballast Point Sculpin recipe actually.

I have never tried moving to a secondary because i am afraid of oxygen exposure, i am still a newbie so i am taking one step at the time.

The bad thing about brewing 1 gallon recipes is i cannot afford to waste any of my precious beer to check the gravity, which leaves me a little lost as when to bottle.

I am planning on bottling after two weeks on the primary, some say its enough, some say it is not.. Any thoughts on that?

You could get a cheap refractometer to check the gravity. Although refractometer readings after fermentation are not accurate because of alcohol content, if you keep getting the same reading after sampling a few days apart, you would know that the beer has finished fermenting. You only need a small drop of beer to use with the refractometer so you wouldn't be wasting much to take a reading.

Two weeks in the primary is probably fine in most cases but it depends on what you are brewing. You definitely want to play it safe and stay away from potential bottle bombs.

I plan to start doing 1 to 2 gallon batches soon and bought a $20 refractometer off Amazon just so I can take small samples to check gravity readings.

EDIT: Ha, IslandLizard beat me to it!

 

[luizffgarcia]

Thanks for the tips.

To be honest, the idea of opening my primary two or three days in a row to check anything scares me a lot, all that oxygen!!! lol

 

[IslandLizard]

You could get a cheap refractometer to check the gravity. Although refractometer readings after fermentation are not accurate because of alcohol content, if you keep getting the same reading after sampling a few days apart, you would know that the beer has finished fermenting. You only need a small drop of beer to use with the refractometer so you wouldn't be wasting much to take a reading.

Two weeks in the primary is probably fine in most cases but it depends on what you are brewing. You definitely want to play it safe and stay away from potential bottle bombs.

I plan to start doing 1 to 2 gallon batches soon and bought a $20 refractometer off Amazon just so I can take small samples to check gravity readings.

EDIT: Ha, IslandLizard beat me to it!

Sorry! Still good to see some other responders in this thread. You know what they say about brilliant minds...

$20 sounds even better. I got one off eBay that's allegedly a bit heavier than the "regular" ones. Shouldn't make a difference on the reading.

Small batches like that are fun and easy to do, mash in a large pot and stick in a pre-warmed oven. Lauter through a sieve or colander. Or use a BIAB bag.

The only trade-off is there's not much beer to show for all the work you put into it. I'd say 2.5 gallons is my minimum cut-off. But I do smaller batches with leftover wort, using a different yeast or so. Or let it sour.

 

[IslandLizard]

Thanks for the tips.

To be honest, the idea of opening my primary two or three days in a row to check anything scares me a lot, all that oxygen!!! lol

You can buy a CO2 cylinder and regulator and flush the headspace. Nitrogen would be fine too. Still, the smaller headspace the better, less CO2 wasted. If you think of kegging in the future that CO2 cylinder can do double duty.

As long as you keep O2 exposure to a minimum you should be OK. Don't blow bubbles with your racking cane or siphon, no gurgling, glugging, or splashing beer when transferring. A little planning goes a long way.

 

[ArthurDigbySellers]

Sorry! Still good to see some other responders in this thread. You know what they say about brilliant minds...

$20 sounds even better. I got one off eBay that's allegedly a bit heavier than the "regular" ones. Shouldn't make a difference on the reading.

Small batches like that are fun and easy to do, mash in a large pot and stick in a pre-warmed oven. Lauter through a sieve or colander. Or use a BIAB bag.

The only trade-off is there's not much beer to show for all the work you put into it. I'd say 2.5 gallons is my minimum cut-off. But I do smaller batches with leftover wort, using a different yeast or so. Or let it sour.

I have the equipment for 5 gallon batches but 2 cases of beer per batch is actually too much beer for me to consume in a timely manner. I've done several 2.5 gallon batches as well but my 1 gallon batches will be used for more experimental beers. If those experiments end up being good, I can then just scale them up to 2.5 or 5 if I want.