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murph999
01-24-2006, 04:47 PM
Like NateDawg, I'm a long time lurker, firt time poster- please be gentle. Awesome forum!!!

My question: Is the smell of acetaldehyde-normal for a cyser/melomel? and, Will it dissipate with time?

My recipe (it tastes good in my mind) is :

~12 lbs orange blossom honey
1 gal Apple cider from Long Grove Apple farm (pasteurized and contains sodium benzoate as a preservative- I was told that in IL it has to contain that?)
3lbs frozen organic blueberries (in muslin sack)
4 camden tablets
5 tsp fermaid K
1/8 tsp pectin enzyme
1 pkt Cote des Blanc yeast
to ~ 5 gallons with spring water


I sanitized like a freak. Fermentation took off like mad and things seemed great. A day and a half later (yesterday) my better half noticed the nasty smell eminating from the ferm. lock on the primary bucket. Research indicates that Acetaldehyde is an intermediary compound in the fermentation of some apples on the way to ethanol. Fermentation is still robust and the smell is not quite as bad as yesterday- but my fear is that the nasty fermenting apple smell is going to permeate my mead. Any advice would be greatly appreciated.

David Baldwin
01-24-2006, 05:13 PM
Welcome to the forum!

I lurked for almsot a year before I set fingers to the keys to ask my first question!


Ok, I've had one batch with a really bad case of aceteldehyde. I found the smell to be very "green apple". Mine mellowed a lot with age, but a year and a half later it is still noticeable.

I can't find the reference right now, but somewhere I read that potassium metabisulfate will help to precipitate the aceteldehyde from the must. Other micro-bio gurus here may have more complete info on that.

Aceteldehyde seems to ba (at least in part) a result of the yeast working under stress of some sort. My issue was too high a fermentation temperature.

I'm not sure that you need to panic yet over the smells. My meads have been all over the map as far as the aromas from the fermentation lock and the smells do change as the fermentation progresses.

David

murph999
01-24-2006, 05:36 PM
Thanks for the quick reply. I bet the high temp is it. I pitched the yeast at ~90 degrees. I'll search for the Na Metabisulphite reference. Thanks again.

mouko_yamamoto
01-24-2006, 08:59 PM
Holy cow, you live in/near Long Grove!?! I live right next to it, in Buffalo Grove!

Brewbear
01-25-2006, 01:00 AM
Welcome to the forums ;D
From what I've read hereabouts, that is one of the "aromas" that could occur.
The temperature that David was talking about was the fermentation temperature. You pitched your yeast in the must at 90 deg., what temperature is the must now? Fermenting at too high a temp will cause the production of fussel alcohols that will take a long time to age out.
You also want to use K-methabisulfide not Na-metha. You mentioned Campden tablets in your first post, they are used to sanitize and if used in the must, a period of at least 12 hours must (pardon the pun) elapse before you pitch the yeast otherwise you might end-up with a stalled fermentation! Since you said the fermentation took off, I will assume you did not usen yet.
With the given amounts, your cyser should have started at SG = 1.097 and %ABV = 13.04. That means that given the yeast used,it will ferment to dry or leave a minute amount of residual sugar.

Hope that helps,
Brewbear

mouko_yamamoto
01-25-2006, 08:37 AM
You have to wait 12 hours before pitching if you use K metabisulfite? Woah, I got lucky. I was wondering how it would work to stop the yeast down the road, but not stop them now.

jaysbrew
01-25-2006, 09:56 AM
Although the fermentation temp is more important than the pitching temp, keep an eye on where you are during the initial pitch as it will certainly affect the yeast as well.

I have been informed (by Winexpert - the wine kit people) that 84 degrees is the magic number for many wine yeasts. Try not to go above it during pitching or fermenting.


Cheers,
Jay

murph999
01-25-2006, 11:19 AM
Thanks to all for your input- I really appreciate it. On day five the smell is already changing quite a bit- more apple-like and less rotting-apple-like. I can see a layer of scum on the top that is forming around the muslin sack- I suspect that is merely spent and/or active yeast adhering to the mass of berries and the actual muslin sack. I'll open it up in a few weeks to rack and remove the blueberries. I post my status then. Thanks again. You guys/gals? are great.

Jaysbrew, my fermentation temp is ~64-70 degrees so I think I'm okay on that

Brewbear- thanks for correcting me- I'll research K-Metabisulfite vice Na. ...those pesty group I earth metals -I always mix those up.
- Also, as for the camden tablets- I dropped them into the water after it had boiled and was cooling- prior to adding the honey and way before adding the blueberries. I'm on day 5 and it's still bubbling like a rabid dog? And my measured O.G. was 1.084- less than your calculation - perhaps due to the higher temp when I pitched?

Mouko- You've gotta love those Long Grove Apple donuts?

Dan McFeeley
01-25-2006, 01:17 PM
Another problem could have been a wide difference between pitching temperature of the rehydrated yeast v/s temperature of the must. This can cause problems for the yeasties, creating off flavors.

mouko_yamamoto
01-25-2006, 07:55 PM
Those things are awesome, only problem is, if I eat one I eat four.