Apple Flavour in the beer.

[dannymartin89]

Hi All,

This is my 4th brew to date. I'm using the coopers DIY kit equipment with a kentish ale LME kit i bought from the local brewing shop. My first 2 brews came out great. (I was using coopers beer kits at the time) but my last one was a coopers canadian blonde. I left it in the primary for 2 weeks. I tasted before bottling and it had a green apple flavour which only got worse in the bottle. I'm told this is a by product from acohol being formed and that the yeast clear this up in time although i reckon it was bacteria in my brew.
I wrote this batch off and now I have started the kentish ale. It's still in primary as we speak for the last 9 days. I made extra sure that equipment was sterilised and clean. Again its constantly at 20 degrees (68F) and followed everything as i always have. I have tasted the brew today and the green apple flavour is there and reasonably strong. I've recorded the gravity at 1015 at the minute. is the batch just needing longer in the primary?
I just want to make sure that i get this batch right and that the apple taste dissapates otherwise i would probably give up on homebrewing.
what do you guys reccommend I do to get this right?

Thanks in advance,
Dan

 

[Kevin79]

There are a few main causes for a green apple/ciders off flavor. Also known as Acetaldehyde

1. Acetaldehyde is a naturally occurring product of early fermentation. At 9 days it is likely to still be present as the yeast probably aren't finished cleaning up yet.

Solution: wait at least two weeks before tasting and measuring gravity and deciding whether or not to bottle. 3 weeks is usually better.

2. Acetaldehyde is more present when fermentation occurs at higher temperature ranges for the yeast you are using. You say the temperature was at 68 degrees. How are you getting that number? If you are going by your thermostat or the ambient room temperature, the temperature in the actually fermenter can be around 5 degrees higher. If you are going by one of those stick on temperature readers, it's important to have it centered on the fermenter to get a more accurate reading and to monitor it more closely during the first few days of fermentation as that is when temps will rise.

3. Acetaldehyde from poor yeast quality or not pitching enough yeast. Always use a good quality yeast and make sure you are pitching enough. If your starting Gravity is above 1.060, you need to consider making a starter or double pitch if using liquid yeast. Also make sure you aerate/oxygenate well to ensure healthy yeast growth. Too little yeast or unhealthy yeast will result in the yeast being unable to clean up the apple/ciders flavor latter on in fermentation.

Hope this helps!

 

[Qhrumphf]

There are a few main causes for a green apple/ciders off flavor. Also known as Acetaldehyde

1. Acetaldehyde is a naturally occurring product of early fermentation. At 9 days it is likely to still be present as the yeast probably aren't finished cleaning up yet.

Solution: wait at least two weeks before tasting and measuring gravity and deciding whether or not to bottle. 3 weeks is usually better.

Often true, not inherently true. If you pitch a proper amount of yeast, aerate properly, and control beer/wort temperature properly (pitch cooler than fermentation temp and go up from there, instead of up then down, or unstable). I usually sample at about a week, and seldom find acetaldehyde present. I usually wait to bottle just because of timing, but I've bottled/casked as soon as 8-9 days without issue (assuming gravity is stable plus a couple days, which is almost always the case), and tapped a cask 5 days later, for barely 2 weeks grain to glass, and had no acetaldehyde present. Because I'm fastidious about aeration, pitching rate, and temperature.

2. Acetaldehyde is more present when fermentation occurs at higher temperature ranges for the yeast you are using. You say the temperature was at 68 degrees. How are you getting that number? If you are going by your thermostat or the ambient room temperature, the temperature in the actually fermenter can be around 5 degrees higher. If you are going by one of those stick on temperature readers, it's important to have it centered on the fermenter to get a more accurate reading and to monitor it more closely during the first few days of fermentation as that is when temps will rise.

3. Acetaldehyde from poor yeast quality or not pitching enough yeast. Always use a good quality yeast and make sure you are pitching enough. If your starting Gravity is above 1.060, you need to consider making a starter or double pitch if using liquid yeast. Also make sure you aerate/oxygenate well to ensure healthy yeast growth. Too little yeast or unhealthy yeast will result in the yeast being unable to clean up the apple/ciders flavor latter on in fermentation.

Hope this helps!

See above. Poor fermentation and yeast management can at best make conditioning take a little longer. Worst case it may leave byproducts at too high levels to be cleaned up.

 

[dannymartin89]

Thanks for the replies guys,

I am using a stick on thermometer which is centred. I haven't changed anything from my first two brews which came out fine. Its strange. I made sure that I aerated the wort before pitching. I used the right amount of yeast but I'm unsure of the quality due to it being in a kit. I guess the best thing to do is to wait it out longer altho I've bottled at this time before and never had this issue.

I'll keep you guys updated and thanks for the help.

 

[dannymartin89]

Hi guys,

Thought id update you on my findings. I did a gravity reading Saturday (its now Tuesday) and the reading was 1015. The reading today showed the same. Shouldn't this have moved by now?

Dan

 

[unionrdr]

Sounds like it may've stalled, barring being done fermenting for some reason. Are you boiling the pre-hopped LME cans? Maillard reactions might be part of the cause. If stalled, then tipping the fermenter on edge & gently swirling to rouse some yeast off the bottom could help. Did you pitch the Cooper's yeast dry? Rehydrating the yeast in 80-90F water for 30 minutes & pitching within 10 degrees of wort temp can also help yeast health. Pitching dry, you can lose up to 50% of the yeast cells. That's why I always rehydrate dry yeast. Rehydrating also cuts lag time.

 

[dannymartin89]

I just stuck the pack of LME in hot water to loosen it then added the pack to hot water out of the kettle. I've read a lot about pitching dry and not. Seems like its divided and I've always pitched dry. Its not the temps as I've controlled the temps. Its a pain in the ass

 

[planetscott]

I used the right amount of yeast but I'm unsure of the quality due to it being in a kit.

That's could be the problem. Next time, buy additional yeast that you know is healthy/viable separate from the kit. When I was doing kits, I never used the yeast included as I never knew the quality. I always bought a separate pack to use instead.

 

[planetscott]

Also, refer to this document for common beer faults.

http://www.bjcp.org/docs/Beer_faults.pdf

 

[kombat]

I've read a lot about pitching dry and not. Seems like its divided and I've always pitched dry.

It's not really "divided" - rehydrating is superior, but some brewers are lazy. I guess you could call that "divided," but the science is in, and sprinkling dry reduces viability by up to 50%. If you compensate for that by pitching more yeast, then you're fine, but it doesn't sound like you did.

The proof is in the pudding (or beer): You have an excess of acetaldehyde. It came from somewhere, and you're reasonably sure it's not temperatures, so what else could it be? You underpitched your yeast, which stressed them. They produced an excess of acetaldehyde, and the combination of being too few in numbers, and the fact that it's an extract brew (with the attendant diminished attenuation) limited their ability to re-absorb the acetaldehyde.

 

[dannymartin89]

So how do I fix this?

 

[dannymartin89]

So how do I fix this?

 

[kombat]

With this batch? Wait. It might diminish some and make it palatable.

With future batches? Aerate thoroughly and pitch a ton of healthy, active yeast.

 

[Toga]

If the green apple flavor is still present let it sit in primary for another week or two then bottle. Let it age for a month before you crack open a bottle. To help prevent the issue in the future don't use the yeast that comes with the coopers kits. It is a good yeast however the little packets under the lid have a couple of issues. The first is there is not a high enough cell count in the package. Not pitching the proper amount of yeast can lead to undesirable off flavors such as what you are experiencing. The second issue is the packets have not been stored under ideal conditions.

 

[unionrdr]

I've found in the past that if the 7g yeast packet is reasonably fresh & you rehydrate, it'll perform about the same as a packet of US-05 pitched dry. did a side-by-side once out of curiosity. But Midwest & NB both carry the Cooper's 15g ale yeast packets. Rehydrated, that bigger packet is a beast. And 65-68F is a good range for their ale yeast.

 

[planetscott]

With this batch? Wait. It might diminish some and make it palatable.

With future batches? Aerate thoroughly and pitch a ton of healthy, active yeast.

The green apple can go away. I judged at a competition a few weeks ago and several of the beers had the green apple flavor. One of them was a friend and he gave me some on Sunday to sample again. There was no green apple that I could detect. He told me the beer submitted to the competition was "green", that is in th ekeg for just 2 days before he bottled and submitted the entries. A few weeks later, better carbonated and in the keg, it was much better. I warmed it, thinking I might get some of the green apple, but never did, so waiting is not a bad idea.

 

[dannymartin89]

guys thanks for all the comments. It's really appreciated. I shall give the brew more time before bottling and will take heed with the yeast info. what are the best yeasts to use with extract kits? is there a generic yeast or will they vary on different brews?

 

[planetscott]

guys thanks for all the comments. It's really appreciated. I shall give the brew more time before bottling and will take heed with the yeast info. what are the best yeasts to use with extract kits? is there a generic yeast or will they vary on different brews?

Depends on the style you are brewing, however the Saf Ale 005, sometimes referred to as the "Chico" strain is a good all purpose yeast. Never be fearful of trying a liquid strain as they can be better suited for particular styles. I really like the Wyeast 1968 for my English ales such as porter, or ESB.

 

[Toga]

For dry yeasts I find US05 to be the most forgiving. It will tolerate a huge range of temps from high to even lower than stated on the package and still produce solid beer.

 

[unionrdr]

True this. It's fermented clean for me up to 74F or more.

 

[snow16]

Absolutely. Give another yeast a shot (US-05, Notthingham) before you think about giving up on homebrewing. You'll be glad you kept at it and well-rewarded with awesome beer.

 

[dannymartin89]

So do I need to pitch more yeast guys or leave it be for longer? The gravity has dropped to 1013 not sure if it ls stalled or finished the fermentation stage.

 

[unionrdr]

Sounds like it's nearly done to me.

 

[1977Brewer]

1.013 is a fantastic FG for extract. It's decent for all grain even. Check again in three days, but I'd bet you're golden.

 

[dannymartin89]

so i just need to hang fire for a week or so before bottling to let the yeast clear up the acetaldehyde?