Newb Question Regarding 'Green Apple' Taste/Smell

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Matty McFly

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Hey gang,

I just started brewing about a month ago with a Coopers DIY kit.

I'm currently brewing a stout that I made with a Coopers can of extract, 250 grams of treacle & 1kg of Coopers brew enhancer 2.

I pitched the yeast at 30 degrees celcius, which was probably a dumb idea (was it? I'm unsure if that matters too much), it's been consistently in the range of 21-24 since. I used a cold yeast from a brew store.

It's been in the wort for about 7 days and has a very strong smell and taste of green apple, which I have assumed is acetaldehyde.

I'm just wondering, will that go away if I leave it for maybe another week or two, or is that there to stay? I had this exact same problem with my first brew, the lager that comes with the kit. I bottled that and left it for two weeks, it still tasted foul so I chucked it.

Thanks guys!
 
Yep, sounds like acetaldehyde.

Fermenting at 21-24 is a touch on the warm side, even for an ale - what yeast did you use?

Leaving your beer on the yeast for a while should result in the yeast cleaning up any acetaldehyde. After this, cold conditioning should also help.
 
Ideally you'd ferment most ales between 18ºC - 20ºC.

30ºC is too hot. 24ºC is too hot. 21ºC is okay.

You say you used a "cold yeast" from a brew store? What do you mean "cold yeast"? Like you just took it from the fridge and then pitched it? Because that's bad.

Also, it's only been fermenting 7 days. Forget about it for a couple of weeks then try again.
 
Really, 18ºC? I've been labouring under the delusion that the warmer the brew, the better. I've been wrapping the fermenter in sleeping bags and such.

By cold yeast I mean it was in a fridge - I didn't let it warm up or anything first, howcome that's bad? Does it shock the yeast a bit? Will the brew be okay or is it a write off?
 
@OP, if you manage to search the forums and get an idea for the biggest newb mistake - 99% of the time, it'll be following the temp recommendations on coopers kits/other kits.

It's simply way too warm. Most ale yeasts will have a range of about 16-20 (14 for Nottingham), lager yeasts, lower again.

Without taking a dig (which I'm not), it seems interesting that you've managed to understand what acetaldehyde is, but not how important yeast handling is to brewing (it's what turns wort into beer, it's that important).

Get yeast handling (temp, type, pitching rates) right and no matter if you're a kit brewing or superbling all grain (or anywhere in between), your beer will massively improve.

Also, 2 weeks after bottling is never long enough to leave a beer to see if it's okay. A month minimum and some beers improve more with age.

Goomba
 
Your yeast should be within a few degrees of the wort at time of pitching. Taking it straight out of the fridge and dumping it into wort is guaranteed trouble.
 
If by cold yeast you mean the brew shop kept some generic brand yeast in the fridge and handed that out cold, well, depends on what shop and yeast they had. But it's doubtful. For example, if all they did was remove the yeast under the lid and keep it in the fridge you are only getting partially viable yeast, it did take a lot of stress in the heat on the truck whatever. Good idea would be to rehydrate it and start it off on a weak malt solution with a little nutrient to encourage it to grow in numbers before pitching. Sometimes you just can't get to the store when you want to and have to work around it...

However, instead of all that farting around you could spend $4.50 and get a saf-ale us05 or other comparable yeast that is stored correctly and has enough yeast in the packet (they are larger than the pouches under the tin). They also come with the correct rehydration and pitching temp and quantity recommendations on the packets.
 
Thanks for the wisdom guys, appreciated.

Is the Coopers yeast that comes under the lid a bit crap then or is it okay? I don't recall what exact yeast I got, it was around $6, came in a blue sachet and had some French on it, the lass behind the counter told me it was an ale yeast.

What should I do with this stout then? Should I leave it at 18 degrees for a few more weeks, will that possibly fix it up or is my brew buggered?
 
Fermentis S04 possibly. It's an English ale yeast but some people have problems with it.

Try and get a hold of Fermentis US 05 (pink packet) and ferment around 18 for a clean tasting ale. It's a neutral US ale yeast.

Under the lid is too small an amount and has been stored outside the fridge for as long as it has been under the lid. Often it is quite sturdy and will handle wider temp variation than the fermentis for example but if you can keep temps lower and consistent, you will get a better result with fermentis.

Slash is suggesting allowing the refrigerated yeast to come to similar temp to your wort before adding so take out of the fridge and let sit for 30 mins or so.

Definitely leave the stout for longer. Stout is a forgiving style and the yeast can clean up their acetaldehyde and other byproducts if given a chance.
 
the yeast was probably this one, the coopers yeast is ok, I'll use that till you master the fermentation temp control, then try different yeasts to see how they taste and if it's worth the additional $6
 
safale-s-04.jpg


This it?

S04 - adequate yeast for the beer made and within style. A considerable amount better than the under the lid yeast.
 
yeastS04.jpg


You'll notice on the back of the packet that the temp range is 15-24 degrees C. This gives you an idea (and this is a bland, but forgiving yeast) of what the maximum this yeast is capable of going to.
 
Yep, that's the yeast I used.

I hope it turns out okay. I'll leave it for a few weeks.

Slightly off topic, but I also have a ginger beer that I bottled a week ago. I had a quick taste this morning to see how it was doing. It tastes a bit off, kind of acidic and very sweet. Other than that, quite nice. Will the acidicy and sweetness go away on its own if I leave it for a month or so?

Thanks for all the help.
 
Depends what you put in the ginger beer.
If the sugar is non Fermentable lactose or something, well.... If its just part way through fermenting expect the sweetness to go down as the sugar ferments out. Acidic... You really have to tell us what you put in that brew.
 
It was just a Coopers GB tin, the yeast under the lid, some grated ginger (a small handful) and 1.3KG of raw sugar.

Perhaps acidic is the wrong word, it's just very, I'm not sure, bitey?

I also primed it with 2 carbonation drops per longneck bottle.
 
Ok, answering in parts. 2 lollies is perhaps a bit high. That might be the sweetness since you just bottled it a week ago. Recommend you keep bottles where a bottle that blows up won't hurt people. Probably be ok, that's what coopers recommend to use but you are learning yet, if there were leftover sugars in the ferment or a weak bottle or two...

That biteyness might be the grated ginger. It will reduce but if that's there at bottling, it won't go away too much. You might start enjoying it.
 
Matty McFly said:
Yep, that's the yeast I used.

I hope it turns out okay. I'll leave it for a few weeks.
Unfortunately that yeast produces lots of esters up around 24 deg C. Next time if you buy off the shelf yeast, get the pink one (US05). But in the mean time it is probably better to use the kit yeast as they are more forgiving for higher temperatures.

I don't particularly like the Coopers kit yeast because it seems to make a strange off flavour. Other brands like Morgans and Black Rock supply pretty good clean yeasts with their cans (from my tasting experiences).
 
Hey MM
I'm a noob too, but I've done a GB a few months ago, so here's my 2c:
That sweetness depends on whether you had unfermentable sweetener in it, like practicalfool mentioned. Mine had Stevia in it, lactose is another common one. I found about half the recommended amount was slightly sweetened & just right - enough to balance the bite from the fresh ginger I put in. The full amount was way too sweet.
So check if you had something like that in your kit (there should be something like that - most of mine was totally unsweetened & was a bit too dry).
If there wasn't, or it's still waaaaay sweeter than that might explain, I'd be concerned about bottle bombs (as per PF, again). A high excess of sugar going into the bottle will produce too much CO2 from the 2nd fermentation & explode the glass. V v bad. & messy. I read there's a pic from one of the guys on this forum from 1-3 yrs ago of a large glass shard imbedded into a wall due to a bottle bomb...

Ka-ching ... 2c!
 
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