Can’t work out contamination issue

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josh18t

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Hey guys been on here for a while and never felt like I needed to ask a question with the amount of knowledge already on here. But I’ve been having some issues since Jan this year and to be honest Im near giving up on hoppy beers as Its costing me a lot of money and is a bit soul destroying.

Sorry in advance for the long winded post.

I only seem to get this problem with very hoppy beers where Im adding huge amounts of dry hops or at least thats when it seems like an issue.

I’ll give an example, I recently made a double IPA using Imperial citrus yeast (the first time using my fancy new stainless conical) and it came out beautifully. The best beer I’ve ever made and, the colour was like orange juice and everything I hoped for and the hop charge was just right.

After one week in the bottle I decided to sample the beer, I was surprised that It was fully carbonated but not concerned it was still exactly what I was hoping for.

After the first week though things went downhill, the colour started turning dark, the beer became over carbonated and after 10 more days It was gushers, every bottle (admittedly opening these at room temp not from chilled). The beer became thin with grassy notes and I guess I’d describe a bit of lingering acrid bitterness and lack of hop taste/aroma. I made this beer with only about 35 estimated IBUs so it shouldn’t have been very bitter.

This has happened with the last 5 IPA style hoppy beers I’ve made recently with the latest literally turning from lighter than orange colour to a greyish brown in 3 weeks. Only some of my current batch are gushers but the flavour of the beer has defiantly changed and become less hoppy. I also see that when I open some of the beers even if they aren’t gushers the sediment instantly gets drawn up the sides of the bottle from the carbonation.

Usually these beers are fine for I’d say two weeks before I get some gushers but they do darken which I always thought was just a downfall of bottling oxidisation rather than using kegs which I don’t really have room for.

The odd thing is that I made a saison In March and its perfect. I’ve had one a week since bottling and its great, nothing wrong at all.


Im pretty certain this is an infection from what I’ve read everywhere and not just tasting beers too early or over carbonating due to the change in flavour and massive change in colour.


If anyone has any pointers on how to track down the culprit that would be a huge help. I’ve been thinking that it has to be something to do with my bottling procedure but the only part of my brewing process that hasn’t really changed is hot side and transfer into fermenter.


My process is:

Make a starter boiling DME for 15 mins, pour into a clean flask (cleaned using oxi then stars), cool, pitch yeast and let it sit on a stir-plate for 2 days covered with sanitised foil (sometimes this gets krausen on it). If I make it further in advance I will chill the flask and decant the beer otherwise I pitch the whole starter.

On brew day I fill my kettle with tap water, treat with a campden tablet and any other mineral additions. I use the BIAB method and a regular 60 min mash/boil.

I chill the wort using a copper immersion cooler and get it chilled to 20C in about 25 mins.

I now use a SS 5 gallon conical fermenter with stainless immersion cooling coil, cooled by a maxi 110 cooler. I transfer the wort to this from the tap on my kettle. I then oxygenate the wort with pure oxygen, pitch my starter, close everything up and fit the blow off.

After I reach my final gravity and it sits there for a couple of days I dump the trub out of the bottom of the fermenter. I’ll usually let it sit for 5-7 days. Dry hop at about 3 days then I’ll cold crash for 1-2 days.

On bottling day I lift my conical onto a table and transfer to my bottling bucket with my dextrose and water solution in it (corn sugar has been boiled lightly for about 15 mins prior). I then bottle .

The bottles have been stored at room temp which obviously fluctuates (particularly in recent months).


Because of the frequency of these issues I’ve been having my cleaning process I believe is pretty intense. Everything that touches the beer post boil is boiled for 15 mins, soaked in oxi and then in starsan (and regularly sprayed whilst attaching tubing etc). The only thing I don’t boil is the whole fermenter without attachments but I scrub that, soak overnight with oxi then spray and soak with starsan.

I have replaced my bottling bucket once now and that is the only plastic that my beer comes into contact with. My bottling wand is stainless and I boil that to. The only other plastic parts are the bottle rinser and tubing which I rinse after use, hang up overnight and then soak in oxi and starsan before use.

My bottles on my last 3 attempts have been brand new as I wanted to eliminate the variable of any past infections. I still fill each with a small amount of oxi then pour boiling water into each and let them soak for at least 2 hours. I then rinse them out and use a bottling rinser full of starsan on bottling day to rinse them out before filling. I also soak my caps before putting them on.


Sorry again for such a long winded post, but wanted to try and give the whole picture.

Thanks in advance.





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Hi.

Your problem does have all the hallmarks of cold side oxidation with the loss of hoppy flavour and change of colour. The increase in bitterness is probably perceptual in that you notice it more without the accompanying hop aromas, and can also be enhanced by the oxidation of beta-acids.

The second issue of over carbonation could be a result of bottling too early or with too much colloidal haze, judging from the description of your beer looking like orange juice. Haze which is then settling in the bottle causing nucleation points for carbon dioxide to gas out of your beer.

Edit: I see that Imperial Citrus Yeast is classed as low flocculating, and a wild Saccharomyces strain, so may require more time to drop out than a well trained brewing strain.

The good, Saison will have likely been less susceptible to oxidation and contained less haze.

I wouldn't have thought it was an infection or contamination of wild yeast as the beer would either be spoilt in the FV or take months to appear in the bottles.

I might be tempted to try a brew without aerating with pure oxygen. You could well be putting in more than the yeast need, leading to a higher level of Dissolved oxygen in the finished beer.

If it's the New England style hoppy beers you are trying to brew, I personally wouldn't bother unless you can force carb and bottle with CO2, I'm afraid.

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A couple of things I can think of:

The darkening is oxidation and has been shown by others to be a definite problem with bottling vs kegging highly hopped beers such as the cloudy NEIPA. To help with this ditch your bottling bucket. It serves no purpose for you other than to oxidise your beer. Batch prime directly into your fermenter, bottle directly from it and cap the bottles quickly. After carbonation, store cold. Cold slows down oxidation.

I'm wondering if the gushers and grassiness are related to hop debris or trub in the beer. Are you bagging the dry hops? You're tapping off the trub, which will also kick a little back up into the beer from the disturbance, but not really cold crashing for very long at all. A week of cold crashing would let everything settle back properly. Another concern is that the volume lost from draining the trub will be replaced with air which will diffuse evenly throughout the headspace over time (that stuff you hear about CO2 forming a heavy 'blanket' is nonsense and contrary to the laws of physics).
 
Thanks guys.

I didn’t realise that low flocculating yeasts and excessive sediment could cause bottle gushers?

Apart from cold conditioning for longer would it benefit from fining with gelatine?

As for priming in the fermentation vessel would this not disturb the trub even more? Or should I measure equal amounts of sugar into each bottle and then bottle from the fermenter?

I don’t currently use hop bags in the fermenter as I heard from a few people that it hinders the aroma. I do use a filter bag when I rack into the bottling bucket to avoid too much hop matter and after bottling there’s a minimal amount of hop matter left in the bucket.

I have also seen some people put a ballon on their blow off would this be worth my while to help when dumping trub/crashing?

My next brew won’t be for a few weeks now as I’m going away but I’d love to change things up for the next batch and probably try to brew the same to eliminate more variables.

As for splashing the beer when racking to the bottling bucket, I’m extra cautious with this.

I also only use brown bottles.


Cheers


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Give cold crashing and add gelatine for a couple of days a try.
I prime my bottles with half a teaspoon of sugar, never had a problem doing this even though technically it is not sanitised.
 
Bypassing the bottling bucket is a good piece of advice. Perhaps getting a syringe and dosing the bottles with the correct proportion of priming solution would add more control.

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Ok thanks I’ll try that next.

I’ll also try hop bags if I’m going to bottle straight from the fermenter as I won’t get to filter them out like I do when I use the bottling bucket.

So just checking incase I’m still missing something. Is it most likely the yeast/hop material that is causing my gushers?

I guess this would explain why on my latest batch about 1/5 of them were gushers, but the rest were only very lightly carbonated and fine apart from the oxidisation. Just inconsistencies in the amount of sediment I’m guessing?


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I think there are valid points here.
Yes beta oxidation, and I would also suspect the yeast has carried on fermenting in the bottle, yeasts with low flocculating properties have a tendancy to continue fermenting, what was your final gravity?
I very much doubt pure O2 is the culprit, yeast will mop this up during propagation.
One thing about NEIPAs and the like, the beer is very unstable, they must be kept refrigerated, even commercial beers, with very low dissolved oxygen, lose hoppy aromas that change with age. Some even want the beer drunk within a few weeks from production. When you go into new territory with hopping regimes, you alter pH, this can alter equilibrium and oxygen maybe scavenged from something that is generally inert.

To check whether the haze is yeast or protein, you can take a small amount of beer in a test tube or the like, add some caustic soda (a bit of thick bleach can work), if it clears, its protein. If not, it is yeast, or indeed hop matter, but this is usually visible as particulates.
 
Personally, and only because I had a similar issue. I would throw away all your piping and buy new.

It’s the one thing you can’t properly clean and it can be the one thing that can harbour bacteria and be near impossible to get rid of.


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Maybe dismantle your bottling wand and see what's going on in there. I dismantle and rinse mine as soon as I've finished bottling. I know you boil it but it might be worth a look.
 
My finishing gravity on my last 2 brews has been 1.014 and 1.015 I had adjusted my mash temp to 67.5 and added 15-20% flaked oats as I wanted a big juicy body. Also added calcium chloride. These gravity readings were held for at least a week before bottling.

As for tubing I replaced all my tubing at the end of April so my last 3 batches have been on fresh tubing.

I do also disassemble my bottling wand when I boil it and I also run the pipe brush I use for my sight glass through it so I’m pretty sure it’s not the bottling wand as I had the same problems when using plastic ones previously.

The amount of gushers I’ve had seems to not be the whole batch like it used to be earlier this year. After hearing everyone’s thoughts on sediment being the problem this might make more sense as it’s only recently that I’ve started using a filter bag when racking to my bottling bucket.

I used to have to disassemble my bottling wand twice while I was bottling as hop matter would clog it up. This isn’t the case now.




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What do you do with your bottling bucket tap in terms of sanitation? I had a similar issue a while back which I eventually pinned down to tap contamination on my bottling bucket (fermenter). Although sanitised it seemed the starsan wasn't really penetrating inside the tap - these really need to be disassembled for cleaning and sanitising. And there is some belief that starsan doesn't effectively kill wild yeasts - not at the usual dilution anyway. What I do now, and found to be much easier is to simply take the tap off and immerse it in boiling water.
 
I know from experience that infections can take a long time to track down and you can go round and round in circles. It may also not just be one thing.

I had a persistent infection a few years ago, some beers were fine but other were infected, went on for 18 months and I never did track down the cause. Had some really bad bottle bombs, beer on the ceiling etc. I got rid of it by soaking everything in a bleach solution , then instigated a more rigorous sanitastion regime whereby I sanitise and then to be doubly sure empty a kettle of boiled water down the side of the FV. Seems to have worked - haven't had an infection since.
 
And there is some belief that starsan doesn't effectively kill wild yeasts - not at the usual dilution anyway.

Usually a belief used as a way to excuse shoddy cleaning.

There's a good piece about cleaning and Star San here.
http://www.milkthefunk.com/wiki/Quality_Assurance

Also this reply from Wyeast suggests wild yeasts pose no more threat than any other contaminants.

IMG_u299z8.jpeg


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