TCP Off-Flavours

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Musby

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Hi all,

As per the thread title, this has now occurred with 2 separate all grain brews (though an intervening brew was top notch). I think I've worked out what the issue with both was, but keen to hear thoughts and general discussion around this issue, and perhaps how to control/prevent this from happening in future.

The first was a Marzen/Oktoberfest lager. I only had 1 Wyeast Munich Lager smackpack (and on reflection should have made a starter). However the Wyeast website reassured me by suggesting starting fermentation at a warmer temp (18-22c ish) before lowering to normal lager fermentation temps.

I pitched the yeast at around 13c, but then naturally warmed at room temp to 18c ish to get the yeast active. This took 3 days before activity, the beer met it's FG fine in a temp controlled fridge, but resulted in a very strong TCP off-flavour/aroma. 12 bottles saved for reference, otherwise it was binned.


The second brew was an English Bitter. The wort went into the stainless steel fermenter at 25c but rapidly cooled to 12c due to the winter temps! I had to wait 3 days in a temp controlled fridge to get it to yeast (S-04) pitching temp of around 18-19c. Fermentation was perfect and FG was met after a week or so. However the TCP flavour has returned.


In both brews 1/2 a crushed campden tab was used in the water. I clean (then thoroughly rinse) with ChemiPro Wash and sanitise with StarSan no rinse. So I don't think it's a chlorine related issue.

My conclusion is that despite the stainless FV being cleaned, sanitised and sealed, in the 3 days waiting for the wort to "warm up" somehow an infection manifested and created some crazy esters in the wort. I'm pretty fastidious with cleaning/sanisiting, so perhaps it could be something else causing the off-flavours?

In future I'll transfer the wort to the FV at a higher temp and allow the stainless to cool it to pitching temp. Then pitch as soon as possible to get yeast activation started.

Interested to hear anyone else's thoughts or experiences with this and any tips or pointers to help in the future.

Thanks!
 

PerthRod

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I suspect the issue is the length of time it's taken for fermentation to start. This has happened to me a few times in the past - it's not helped by frequently opening the FV to see if it's started !!
 
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I suspect the issue is the length of time it's taken for fermentation to start. This has happened to me a few times in the past - it's not helped by frequently opening the FV to see if it's started !!

Yep, I'd agree with that, I had tcp in two consecutive brews in 2019 and think that it was because the original yeast I used didnt get started. Like you I waited 3 days for it to start and pitched us05 in the end but it was too late. Think the 2nd off batch was me not cleaning the fermenter well enough after the original infection.
 

Galena

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A medicinal flavour (Chlorophenals) result from reactions involving chlorine-based sanitisers (bleach VWP etc) and phenol compounds. So if you have used them then you need to ensure you have not exceeded recommended concentrations and that they are rinsed well and dried before use.
John Palmer - How to Brew.
 

Hop_it

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The chlorophenols can also result from reactions with a chlorinated water supply. I know that 1/2 a Camden tablet was used, but was it fully dissolved and dispersed, and did you leave it long enough? I leave mine overnight in my HLT, and never had this problem.
 

H0PM0NSTER

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I've had the same taste after yeast has failed to start properly. Not sure if it's caused by the wort becoming infected in the extended period before the yeast gets going or just a by-product of the yeast being stressed.
 
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I've posted on the is topic before - you always get the replies suggesting it's due to chlorine in either the water or the cleaning products. If that was the case, it would occur every time, not intermittently.

If you only get it in some brews I'd agree with the other posters and say stressed yeast. The last time it happened to me was about 18months ago mid-summer and I think the brew just got too hot in that case due to an unexpected heatwave.
 

Galena

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you always get the replies suggesting it's due to chlorine in either the water or the cleaning products. If that was the case, it would occur every time, not intermittently.
With water yes but with cleaning products, have they used chlorine based products for every brew? Have they rinsed less effectively on some occasions?
 

trummy

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Bit concerned now! Just bottled a Muntons APA that took 3days to get going and 3 weeks to work out. Guess it was too cold in the kitchen. I have never dried rinsed containers, always thought more chance of introducing bacteria drying with a tea towel. I do treat the brewing water to a Camden tablet but too much faf trying to cut one in half, so a full tablet is used and all left overnight
 

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So look there is an area that many people overlook and never pay close enough attention towards but do cause soo many of the off flavour issues people say they have. Also, no offence meant, but we do assume people are able to describe the off flavour correctly.

Anyway, yeast pitch rate is VITAL!! So pitching plenty of healthy yeast that you have fermentation start within 24hrs is critical. If you pitch and ferm doesn’t get going for 48+ hrs the yeast has been stressed due to not enough healthy cells to the gravity and/or volume.

For the cost of dried yeast ALWAYS over pitch (ie two packs) on a nothing north of 19 litres and/or over 1.058 SG. And do a starter or have SUPER fresh wet yeast. Even then I would suggest a starter.

A quick start to ferm also staves off a bacterial infection because the lower ph keeps the nasties at bay. Unless your cleaning your FV with a bog brush.

Basically really look and care about your yeast pitch rate and yeast health and also during ferm. Big swings hot/cold again will create the same off flavour issues.

Remember we mash and create wort. Yeast makes beer and is maybe the most critical part of the process after cleanliness.
 
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I can relate to this, I have a full batch of German bock that has this taste. Fermentation took ages to get going, I used old slurry with out a starter.
 

Hoddy

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I can relate to this, I have a full batch of German bock that has this taste. Fermentation took ages to get going, I used old slurry with out a starter.
There you go. It’s an all to often overlooked issue. Easy to blame the ingredients and water.
 
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There you go. It’s an all to often overlooked issue. Easy to blame the ingredients and water.
IMG_20211220_204801759.jpg
That's the beer, caught out for being lazy. I used the same yeast twice before with no issues. Starter made each time, you live and learn
 

Hoddy

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View attachment 59990
That's the beer, caught out for being lazy. I used the same yeast twice before with no issues. Starter made each time, you live and learn
There’s nothing wrong with re-pitching and rising yeast. Hey I’m on generation 7 (7th re-pitch) of a single packet of Verdent yeast. It’s all about knowing the needs of what you want to ferment and making sure you have enough cells to deal with it.

Makes a massive diff to your beer quality.
 
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Hi all,

As per the thread title, this has now occurred with 2 separate all grain brews (though an intervening brew was top notch). I think I've worked out what the issue with both was, but keen to hear thoughts and general discussion around this issue, and perhaps how to control/prevent this from happening in future.

The first was a Marzen/Oktoberfest lager. I only had 1 Wyeast Munich Lager smackpack (and on reflection should have made a starter). However the Wyeast website reassured me by suggesting starting fermentation at a warmer temp (18-22c ish) before lowering to normal lager fermentation temps.

I pitched the yeast at around 13c, but then naturally warmed at room temp to 18c ish to get the yeast active. This took 3 days before activity, the beer met it's FG fine in a temp controlled fridge, but resulted in a very strong TCP off-flavour/aroma. 12 bottles saved for reference, otherwise it was binned.


The second brew was an English Bitter. The wort went into the stainless steel fermenter at 25c but rapidly cooled to 12c due to the winter temps! I had to wait 3 days in a temp controlled fridge to get it to yeast (S-04) pitching temp of around 18-19c. Fermentation was perfect and FG was met after a week or so. However the TCP flavour has returned.


In both brews 1/2 a crushed campden tab was used in the water. I clean (then thoroughly rinse) with ChemiPro Wash and sanitise with StarSan no rinse. So I don't think it's a chlorine related issue.

My conclusion is that despite the stainless FV being cleaned, sanitised and sealed, in the 3 days waiting for the wort to "warm up" somehow an infection manifested and created some crazy esters in the wort. I'm pretty fastidious with cleaning/sanisiting, so perhaps it could be something else causing the off-flavours?

In future I'll transfer the wort to the FV at a higher temp and allow the stainless to cool it to pitching temp. Then pitch as soon as possible to get yeast activation started.

Interested to hear anyone else's thoughts or experiences with this and any tips or pointers to help in the future.

Thanks!
I have just been reading something about this recently, you have to be aware too cool or too warm puts the yeast at a disadvantage. There is bacteria out there which can take advantage of the yeasts slow response, and they are quick. This happens at lower and higher temperatures. Not always, just unlucky when it does. Kitchens are one of the most contagious places to brew, lots of sugar in kitchens therefore lots of bacteria and wild yeasts ready and waiting to take advantage of a sugar hit. I recently put an open bottle of wort in the kitchen to sour, it had cheese cloth over the top next morning it was starting to get krausen. I brew outside and pitch in a fermenting room, but I have been caught out, thinking anything dominant in the fermenting room would be one of my own yeasts.
 

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The yeast can also be stressed by pitching a yeast that is warmer than the wort, apparently the yeast is happy to be warmed to fermentation temperature but if the yeast is pitched to a cooler wort it is not happy.
 

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I’ve only had this once, and I didn't get to the bottom of it. With subsequent brews I just tried to pay extra attention to cleanliness.
 

trummy

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I have tried the Muntons APA today (23/12 entry but started 25/11, I brewed it too cold) and its fine, still a little cloudy but the taste had no off flavours I could detect. Let the wife try a small glass and she agreed it is ok. (Better sense of taste than me but don't let her have too much in case she starts helping herself)
I used to get off tastes before I started adding a Camden tablet overnight to the tap brewing water
 

labrewski

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I definitely blame bleach I got a few brews that created an awful taste absolutely undrinkable in my case I used a little bleach to clean fv
Haven't used bleach since problem dissappeared
 

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