Infection/Quality Problems: what we should know

untrue. the beer will continue to develop, just not as much and not in the same way. the taste of aging is oxidation, for the most part, and pasteurization will have little effect on that in the long run. yeast isn't responsible for much of the change in flavor over time of stouts, it's mostly chemical changes.

sour beers, on the other hand, do continue to develop due to the activities of yeasts and bacteria. pasteurizing a sour will have a much bigger influence over the impact of time.

 

Did you read his post of: "No, it's due to the Brettanomyces in the case of Russian Stout."

I have cellared a number of beers brewed with Brett (both homebrewed and commercial). Those beer definitely 'evolved' over the years from the presence of live Brett.

Cheers!

 

I beg to disagree. The whole point of having the Brettanomyces present is to stop oxidation. I had a Russian Stout from the 1970's a couple of years ago that had no trace of oxidation.

Oxidation plays a role but it isn't the only factor. Ber ageing is an incredibly somplex process. Anyone who tells you they fully understand it is a liar. The person who know more on the topic than most anyone, John Keeling, disagrees about a pasteirsed beer maturing much the same as one with live yeast. It's easy enough to make the experiment yourself. Get a bottle of Fullers Vintage Ale and one of Golden Pride and leave them in the cellar for a year or two. They're the same basic beer, except Vintage Ale is bottle conditioned.

 

@SFACRKnight, Ron has an experiment for you above ^.

Cheers!

 

Good point. I mostly live in the past.

 

i'd like to hear the role barrels play. i asked a question recently & got the answer i figured had to be correct. we know that under right conditions, although alcohol evaporates faster/easier than water, when maturing American whiskey, it's common knowledge that water can & more often than not, does escape barrels at higher rates than alcohol will. to me this means things that don't belong can probably also get in the same as water can get out - the answer was yes.

something i've pondered for years now. back around 2011 or so, there was a pretty extensive blog post with quite a few decent quality photos of GI's barrelhouse & program. in close proximity appeared to be wine barrels intended for sour/wilds with stacks of bourbon barrels. would again assume the answer is yes but curious what others think on whether the observed practice (barrels of mixed styles/formats in same general space) increases risk? it's my understanding they've continued this practice to date. & if this is believed an added risk, have they just been extremely lucky to this point in time?

also, it's my assumption whiskey barrels probably have a bit of natural defense against unwanted organisms due to the amount of alcohol they once contained; portions of which generally would still live in the walls, floor & ceiling wood. would the alcohol in a typical spent barrel amount to a defense? and if so, would 35 year old barrels that almost certainly were approaching bone dry if not already to that point, amount to barrels of less/no natural defense? IOW could 35 year old barrels pose bigger risks due to (1) complete loss of alcohol (2) wearing/breaking down from usage over a longer than usual lifespans?

 

indeed, i missed that. sorry. i somehow missed that we were talking about Courage russian stout in particular. i was thinking russian stouts in general.

brett in russian stout is not standard. Courage RS apparently had some, per the Mad Fermentationist', but i'm not aware of any other RS that has brett. nowadays, an RS with brett would be considered infected.

absolutely agreed. but i'd wager that none of those beers were russian stouts.

i apologize if i'm talking in circles here...

 

I can't respond about cross-contamination of bacteria between barrels specifically, but I suspect proving direct migration of bacteria between barrels would be difficult. However, it's impossible to decontaminate every inch of a building, so if beer-souring bacteria was in the building at one time, there could be unknown colonies of that bacteria surviving somewhere that if conditions were right could potentially cross-contaminate. This is the reason why some brewers with sour programs will partition their brewery or even purchase a separate facility (The Bruery Terreux for example) for sour brewing to avoid cross-contamination to their non-sour beers.

 

Some strains can become airborne, too- hard to defend against that.

 

yeah. thanks for the response. i don't expect anybody to be able to conclude/declare *proof* "That's it". more so curious about what's possible or perhaps even likely, if the right conditions exist.

 

Absolutely... some sour brewers, like Cantilion, depend on it and purposely do not disturb the unique biome living in the walls, ceiling, and rafters of the brewery.

 

Sometimes it's shared tools and equipment between the "wild' and "clean" barrels. Sometimes it's contamination during QA sampling. Sometimes it's just flies. Barrels have a tendency to leak or foam a (such as barrel fermentations), and this can become a food source for flies. Flies can be a mechanism to move a culture from one barrel to another.

 

I don't think I would boil the bag - not sure why you would do that. I suppose it would thaw really fast and at least does no harm. If adding to the "cold side" of the process, maybe spray down the bag with no-rinse sanitizer.

Remember that this conversation with Jack and I was pretty much hypothetical wondering aloud. We were wondering if a beer made with completely "green" hops straight from the field and added to the "cold side" of the process could develop an incipient infection due to the cooties that may (or may not) be residing in the hop cones.

You dried, you froze, you vacuum sealed...seems you'd be good to go.

 

Welcome to the BA site, cr3. I don't know the answer to your question because I do not grow my own hops. If you post your question in the Homebrewing forum you'll get replies from homebrewers who have probably been in your position.

 

Dave, just to double check you are referring to dry hopping with freshly picked wet hops?

I homebrew a wet hopped harvest ale every year using the hops from my plant in my backyard. I only add those wet hops to the kettle. I have never dry hopped using those wet hops out of concern there may be small insects (i.e., vectors for bacteria) within those hop cones.

FWIW I have consumed my Harvest Ales with up to 10 months of age. I wonder if I would have that same beer stability if I dry hopped with wet hops.

Cheers!

 

Thanks for the info!!!!

 

I understand infection in packaging, but how can tell if a keg has infection or if a tap line wasn't properly cleaned?

 

I think the bartender will know about most infections because every one that I've seen in a bottle (I've not seen a draft version) has been way over-carbonated. I assume the bartender would not be able to pour a glass of an over-carbed beer. Typically there is a very sharp-on-the-tongue taste to the beer too (not just sour), so that also tells you about an infection. Probably any other off-flavor that just does not seem natural (not 'beery') would be the best way to describe what dirty tap lines can do.