Questions from a newbie regarding Oxidation and Racking

[TheBS19]

Hey all,

Me and my buddy have completed 3 extract brews (3rd one is bottle conditioning now - have had a taster so far) and we've used these forums as a great resource for our questions along the way. I know its all trial and error, but I've noticed a consistent "off" flavor in our last 2 kits that wasn't there in our first. After trying to retrace my steps and figure out what we did differently to cause this, and what this "off" flavor might be, I think I've found it may be down to 2 things:

1) The "extract" off flavor that some describe by letting the DME caramelize during the boil could definitely be it - I've read about doing the late add at flameout and also about taking the kettle off the heat when adding the initial extract and will test these methods during out next brew.

2) Potential oxidation gained either through oxidizing hot wort, or during racking procedures, or perhaps overzealous checking of the primary fermenter.

I would best describe the off flavor as being "yeasty" and the brews are definitely a bit cloudy. However, my palate may not be sophisticated enough to truly pinpoint it. Anyway, related to some "common mistakes" I've been reading up on that we could be making, wanted to propose 2 questions to the "experts" here and see what we might be messing up. Thanks in advance.



1. Preventing oxidation of the wort: We don't have a wort chiller so during our first 2 batches when temperatures were warmer, we used a tub filled with ice to try and cool our wort. I believe we kept the brew kettle's lid off during this - looking back, is this a big no-no? And during the most recent batch, since we were in the dead of winter and had some convenient snow piles in my yard, we put the kettle right into one of those (again, the lid may have been off). Additionally, we stir the cooling wort around to try to get the warmer wort at the bottom of the kettle to react to the cold air. This could all be a big mistake - without a wort chiller for now, would a better method of cooling just be to cover the wort and put it in an extra fridge? I'm lucky to have basement fridge that I could take the racks out of and easily fit the brew kettle in there?

Additionally, to aerate our wort, my partner has a pump he otherwise uses in fishing (not a fisherman myself so I don't necessarily understand it) that we keep on the additional 2.5-3g of water that will be added to the chilled wort and we splash our wort on top of that (straight from brew kettle to fermenter). Is that not sufficient aeration? On the opposite end, is the "splashing" of the cooled wort potentially oxidizing it?

2. Racking procedures: I know I've read enough know to believe that a secondary is probably not necessary. I think what we're going to do this time is strain our wort into the primary and try to just leave it in the primary for 3-4 weeks before going right to the bottling bucket. Questions on this:

- Is the plastic "kit" primary bucket preferable to a plastic carboy for a primary fermentation? If I'm only using one of the other (eliminating the secondary process), which should I use, and why?

- What are the best ways to prevent any oxidation potential if we did decide to rack to a secondary? We've used a racking cane and siphon to date for this and may have made errors. First, obviously we remove the air-tight lid on the primary to take our FG readings and start the racking process and leave it off throughout - should the lid be replaced while the siphon is going? If so, how can you siphon through the standard grommets (our racking cane is quite a bit thicker than the grommet). Then, to get the siphon started, I've been just doing the "sucking" technique, which is probably an issue - whats a better way to start the siphon if you DON'T have an auto-siphon? Then, while I'm careful as the carboy fills to ensure the siphon is below the beer line, obviously initially there is no beer line and splashing seems inevitable (as well as an open top in the carboy) - I'm thinking this may be where I'm getting the worst oxidation potential. How is this avoided? Finally, if there is extra room in the carboy, should this be somehow filled? My latest batch turned out to only be about 4 gallons presumably due to some boil off and a lot of trub in the primary left behind - did this extra space in my carboy cause some problems? Finally, during the racking process to the bottling bucket, I think my kit instructions tell me to stir the priming sugar (after its boil) into the transferred flat beer, but does this stirring in the un-topped bottling bucket again cause some oxidation? Whats the preferred method HERE?



Thanks again everyone. I know this is a LONG post, but I really appreciate any feedback that can be provided. I think the good news is that the "off" flavor I've tasted is definitely consistent so I assume its something easily correctable in our brew process and hoping to just pinpoint where its originating from.

 

[flars]

That is a very long narrative. Let's slow down a little bit. What were your first two brews? What were the OGs and FGs for the primaries? How long did you have each one in the primary, and it sounds like you used a secondary for each one, how long in the secondary?

 

[TheBS19]

First 2 brews were an English Pale Ale and American Pale Ale, each Brewer's Best kits.

I'll have to look up my exact gravities later in my notebook at home (at work now) but the OG's were within the recommended ranges on the instructions. The FG for the English was in the range, the FG for the American was slightly higher than recommended (but gave it a while and nothing further happened).

The English stayed in the primary for 7 days (had a really vigorous fermentation - 24 hours after brewing, the lid got blown off the primary and foam was everywhere - had to use a blow-off) and then stayed in the secondary for 2 more weeks. This was our first and the final product was excellent - good hoppiness, good coloring, no off-falvors.

The American had far less of a fermentation. Was actually concerned there was no fermentation a few days in due to the lack of airlock activity (have learned not to trust it, but the differences between the two scared us). Stayed in the primary for 2 full weeks (may have even been 15 or 16 days - have to check the notes), got racked for secondary for another 2 weeks. Never got close to the clarity of the first, off flavors present, FG was higher than recommended and made for only about a 4% ABV ale.

The most recent batch was a Milk Stout, again, Brewer's Best. We kept it in the primary for 2 weeks (fermentation seemed fine) - OG was within specified range, FG was again higher than recommended. Transferred to secondary for another 2 weeks and has now been bottle conditioning for 3 weeks as of tomorrow - sampled a bottle about 3 days ago and had same off-flavors as the 2nd batch. Good head/carbonation and coloring on it, though.

 

[flars]

Two weeks in the primary is good. Three weeks even better. What was the temperature of wort during fermentation?

 

[TheBS19]

Two weeks in the primary is good. Three weeks even better. What was the temperature of wort during fermentation?

I used the built in thermometer on the primary bucket that came with the whole Brewer's Best kit to monitor.

The most recent (the stout) it was a consistent 64 throughout.

The first two were closer to 70, but fairly stable.

The problem is that I can keep it consistent (I use the tub in my bathroom in our finished basement for storage during fermentation - baseboard heating in the room and I control the temperature for the basement as a whole using its own thermostat) but I can't manipulate the temperature much in my current setup. We brewed the first two during the warmer months when room temperature was just higher - this one was brewed in January when room temperature was lower. Consistent, but still a slave to room temp.

 

[flars]

The off flavors you are tasting in your first two brews is probably from to high of fermentation temperature. fermentation is exothermic. Depending upon the amount of yeast pitched; the temperature of the wort can rise 5° to 15° during the first 36 hours. (I am also thinking you protected your fermentors from sunlight and flourescent lights.) Your current brew a t 64° is perfect. If you can control ambient room temperature is a plus. To better control the temperature of the wort when it is warm is to go with a swamp cooler. I use a resturant bussing tray filled with water. The fermentor is wrapped in a cotton towel or cotton sweatshirt. Cotton wicks better than any other material. Adding a fan to the set up can reduce wort temperature 8°. Don't cover the fermometer strip or it will record the ambient temperature caused by evaporation, not the wort temperature.

 

[TheBS19]

The off flavors you are tasting in your first two brews is probably from to high of fermentation temperature. fermentation is exothermic. Depending upon the amount of yeast pitched; the temperature of the wort can rise 5° to 15° during the first 36 hours. (I am also thinking you protected your fermentors from sunlight and flourescent lights.) Your current brew a t 64° is perfect. If you can control ambient room temperature is a plus. To better control the temperature of the wort when it is warm is to go with a swamp cooler. I use a resturant bussing tray filled with water. The fermentor is wrapped in a cotton towel or cotton sweatshirt. Cotton wicks better than any other material. Adding a fan to the set up can reduce wort temperature 8°. Don't cover the fermometer strip or it will record the ambient temperature caused by evaporation, not the wort temperature.

Can you explain the concept of a "swamp cooler"?

And the problem is that the first brew DIDNT have off flavors, and the last two (including the one fermented at the consistent 64) DID, which throws me off. While I think I can do better to control temperatures, I don't think I can attribute my issues thus far to that - the fermometer strip has shown that the temps have remained pretty consistent throughout fermentation, and the first two batches despite at a consistently similar temp, produced very different flavors and the 3rd, at a consistent, lower, more ideal temp, produced the same off flavor as the 2nd.

 

[TheBS19]

BTW, I appreciate you taking the time to help me out here!!

Any thoughts on potential oxidation issues as described in my original, tragically long-winded, narrative??? Thanks!!

 

[masterfool101]

What yeast and hop schedules did you use for the 3 beers?

One other thing to think of is that what you're tasting isn't an "off" flavor at all . . . simply a flavor profile you don't much care for. It could be completely normal.

That being said, let me answer some of your questions:

1) An ice bath/snowbank is a great way to cool your wort . . . but don't stir the wort while it's hot. That's a major factor in hot side oxidation. Let it sit and cool. I leave mine covered, but open air can work as well, as long as you don't disturb it too much. I'm not saying NEVER stir . . . it can help cool down the wort . . . but don't stir vigorously until the wort is under 80deg.

As for the pump, make sure it's rated as "food safe" . . . else you're asking for trouble. Also, how do you clean the pump? Improper cleaning may result in infection. That being said, splashing cooled wort is one of the best ways to oxygenate it, and the yeast need that oxygen to build healthy cell walls, and produce good beer.

2) For primary fermentation, it makes little difference whether you use a plastic bucket or plastic carboy. There are advantages to both, and disadvantages to both. But as long as they're food safe, and have a good way to seal them (either a decent lid, or appropriately sized stopper), you're probably not going to notice the difference over the 3-4 week period your beer will be in primary. As a PERSONAL preference, I like the carboys, as most are transparent, letting me see what is going on. But note: you MUST keep these covered so that sunlight (or even fluorescent) doesn't get at them and skunk them.

As for siphoning: GET AN AUTO SIPHON! No sucking. They're not that expensive, and they're really easy to use. Beyond that, make sure you have enough hose to go all the way to the bottom of your secondary vessel, so you minimize splashing. Don't be afraid to let the siphon happen slowly . .. it won't hurt. There is some oxidation that will occur due to siphoning, and due to excess oxygen in the headspace of the new vessel. Best way to reduce that is to get a vessel that nearly exactly matches your batch size to reduce this headspace. Unlike a primary, a secondary doesn't need "room" for anything like krausen.

With regards to priming sugar: Mix the sugar into about 1 cup of boiling water, and let it cool slightly. Place that in the bottom of your bottling bucket. Siphon beer on top of it. You shouldn't need to stir, as the sugar and beer should mix well during the siphon.

 

[TheBS19]

What yeast and hop schedules did you use for the 3 beers?

One other thing to think of is that what you're tasting isn't an "off" flavor at all . . . simply a flavor profile you don't much care for. It could be completely normal.


.

Yeast- has been Nottingham (dry) for each. That's just what came with the kit.

Hop Schedules- followed the kit instructions exactly on each. Would have to look back to recipes for exact procedures but did not deviate at all.

On the flavor- I think it's an "off" because its showed up in 2 very different styles but not the 1st batch, which was a more similar flavor profile to the 2nd batch (certainly closer than the 2 that share the "off").

Thanks for the tips- yeah, I need to get an auto-siphon!