Aftertaste issue

[CraigR]

i have just brewed my 17th batch on my Grainfather, with generally excellent results .

A good mix of ales and porters, but with less success with lighter beers, (lighter coloured not low alcohol).

2 batches, number 7 and number 17, both variants of a pale ale brewed several months apart have a distinct aftertaste which I don’t believe was present in the wort, but showed up during fermentation.

I am convinced there are no issues with sanitation, but can’t put my finger on the cause.

Looking up types of off flavour, it is difficult to be certain without a reference, but I am leaning towards chlorophenols.

I checked my local water report, no chloramine is used, and chlorine levels are typically 0.35ppm (with a high of 0.6) which seems quite low.

Would love to know if there was a way to confirm what the off flavour is, without resorting to expensive testing.

Grateful for advice / suggestions

 

[OnePlate]

Do you use campden tablets to dechlorinate your water?

 

[CraigR]

Thx for quick reply.

I haven’t added anything to my water as yet, (other than to drop the ph in some batches where alkalinity is a little too high).

I ordered some metabisulphite powder from my local hbs as a ‘belt and braces’ solution, as problem has only occurred twice, and still not certain is chlorine level

 

[EnglishAndy]

Are you cleaning or disinfecting with anything containing bleach or other chlorine source? A bad idea with stainless steel anyway but thought it worth asking.

 

[CraigR]

I use a homemade PBW for cleaning, and starsan to sterilise

 

[madscientist451]

Bottling? Kegging? Temperature controlled fermentation? Re-using yeast?
Pitching enough yeast? Getting complete attenuation? Oxygen getting introduced somewhere?
There are many possible variables that could contribute to off flavors.
I noticed big flavor improvements (was having an occasional aftertaste issue) when I finally got temperature control for fermentation and kegs. I also make sure I pitch a healthty, large quantity of yeast.

 

[CraigR]

this time I bottled, but the taste is there after fermentation.

I also keg some brews, or a mix of both

I use an inkbird thermostat and fridge so temperature is well controlled.

On this occasion (batch 17) I used a kveik voss yeast which i top cropped from my last beer and fermented at high 20s, well within its capability.

FG is 1009/1010 and ABV is about 7.5% which is slightly stronger than intended, but close to predicted.

when it last happened (batch 7) i used a dried yeast (safeale 04 I think) and fermented at 20/21

 

[Jag75]

If your fermentation temp is good and your stuff is clean and you have that chlorophenol it's got to be your water. Your water is better for the darker beers then the lighter as mine is the same way. Try using Ro water and build up your water profile . I'm willing to bet you wont have any issues and it will make great beer.

 

[ncbrewer]

I ordered some metabisulphite powder from my local hbs as a ‘belt and braces’ solution, as problem has only occurred twice, and still not certain is chlorine level

Good chance this will take care of it. If not, no harm done.

 

[CascadesBrewer]

So you have a plastic/band aid type flavor?

My two most recent beers have that. It gets much more noticeable when the beers warm up a little. I thought the first one was just flavors from the yeast (WLP500), but then my next beer (a Pale Ale fermented with WLP001) had the same fault.

I have not 100% figured out the cause, but I suspect either chloramine or infection. I replaced my very old bag of campden tablets with new (though if that was the cause it would be odd to go from no problem to two in a row). I gave all my plastic and small items a cleaning and soak in Iodophor (I have been using Starsan). I have 2 lagers fermenting now and when I took a sample a few days ago I did not detect any off flavors, so hopefully I have kicked the issue.

This article seems decent if you have not seen it: https://learn.kegerator.com/off-flavors-in-beer/

 

[CraigR]

Cheers to everyone from their input

Making a pale Belgian next, pretreating with a bit of metabisulphite.

Will let you know how I get on

 

[Bubbles2]

Wait 24 hours after using your Meta sulph in your water, unless boiling will get rid of it...

 

[RPh_Guy]

Wait 24 hours after using your Meta sulph in your water, unless boiling will get rid of it...

That's not necessary.

 

[CascadesBrewer]

Wait 24 hours after using your Meta sulph in your water, unless boiling will get rid of it...

My understanding is that the reaction with metabisulphite happens in seconds. Letting water sit for 24 hours (overnight) is supposed to gas off Chlorine but not Chloramine...the same for boiling. Metabisulphite should treat both Chlorine and Chloramine.