Why the f#$% does my beer's flavor change???

I am getting really pissed about the changes to my beer. After it has been fermenting for seven days I take a hydrometer reading then taste the beer in the glass (I'm guessing everyone does this as well). I check it today (day 8), same gravity reading and BAM! The malty notes - GONE, the hop aroma/flavor GONE. I can't believe an entire batch can 1) get infected within 24 hours and 2) can change its entire flavor in 24 hours. WTFFFFF!

Beer changes a LOT over the fermentation/conditioning/aging process. Most of us let the yeast do their work in peace, and taste it after a month or so in the fermenter and a month or so in the bottles.

What does the flavor change from and to? They will evolve through the fermentation process because the yeast is doing it's thing, but as far as the malty notes being completely gone and the hope aroma/flavor being gone... I don't have the slightest clue that would cause that except some wild yeast/bacteria maybe?

The problem I think I'm having is some sort of oxidation or waiting too long to keg. I've had guys who swear by keg transferring after a week for ales and two weeks for lagers. I have wanted to let the yeast fully consume the sugars in the fermenter rather than have a bunch of sludge in the bottom of my keg.

Let's not freak the man out about infection/wild yeast. The flavor changes because that's just how fermentation works. Leave it alone until it's done fermenting.

girdwood said:

What does the flavor change from and to? They will evolve through the fermentation process because the yeast is doing it's thing, but as far as the malty notes being completely gone and the hope aroma/flavor being gone... I don't have the slightest clue that would cause that except some wild yeast/bacteria maybe?

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That's the only thing I can think of but I only break the seal of the fermenter in order to relieve the pressure drop from opening the spigot. I know the fermenter was sparkling clean at the time of transfer from the boil kettle so unless the air around the fermenter is nastier than a Louisiana swamp, I can't see it infecting the entire batch in 24 hours.

JonM said:

Let's not freak the man out about infection/wild yeast. The flavor changes because that's just how fermentation works. Leave it alone until it's done fermenting.

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Three days of the same gravity reading so I am assuming the bulk of fermenting has completed. I have since begun the cold crash so I can keg this one around Thanksgiving. Hopefully you are right Jon. I appreciate it.

LutzBrauerei said:

Three days of the same gravity reading so I am assuming the bulk of fermenting has completed.

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Yeast continue to clean up after themselves for a while after "fermentation" is complete. Just because it has reached terminal gravity doesn't mean it's done. How long do you primary? I've taken to the practice of primarying for roughly 3 weeks before crashing and bottling thanks to advice from members here.

TexanRudeboy said:

Yeast continue to clean up after themselves for a while after "fermentation" is complete. Just because it has reached terminal gravity doesn't mean it's done. How long do you primary? I've taken to the practice of primarying for roughly 3 weeks before crashing and bottling thanks to advice from members here.

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I normally go 12-14 days in the primary before crashing for five days, then keg condition for a week before pumping up the carbonation.

If you normally do 12-14 days, then maybe go back to what you originally did. 7 is too early.

LutzBrauerei said:

The problem I think I'm having is some sort of oxidation or waiting too long to keg. I've had guys who swear by keg transferring after a week for ales and two weeks for lagers. I have wanted to let the yeast fully consume the sugars in the fermenter rather than have a bunch of sludge in the bottom of my keg.

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not sure a lager can be ready in two weeks.

LutzBrauerei said:

The problem I think I'm having is some sort of oxidation or waiting too long to keg. I've had guys who swear by keg transferring after a week for ales and two weeks for lagers. I have wanted to let the yeast fully consume the sugars in the fermenter rather than have a bunch of sludge in the bottom of my keg.

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There are some ales that could be kegged after two weeks, such as cream ales and some pales, but something like a brown ale or stout will not be very good that quickly. Two weeks for a lager is laughable, I don't even start to lager until after two weeks then another five at least before I keg. I think your problem is rushing it too much, the most important ingredient in great beer is patience. Leave this beer alone until day 18 and start testing gravity then. If stable on day 21 keg it, wait two weeks on the gas and then try it. Carbonation in a properly aged beer will release the flavors when you pour.

I take a gravity reading when I think the brew is done (minimum 3 weeks). Normally taste the gravity sample but unless there's a glaring error don't fret or taste it again until it's carbed in the bottle/keg a few weeks later.

Most of my brews have changed in a positive way over the course of bottle conditioning.

I think the OP meant transferring to the keg to lager, not being ready to drink in 2 wks. That's what I do too.

I had an English bitter that had some spots of an infection forming on the krausen that topped the beer after about 2-3 weeks.
I racked from under the krausen and then something strange happened.
The beer was as you described: the malt and hops flavour was lost and there was some off flavour. Probably a vinegar bacteria.
After 2 weeks in the keg it still tasted like $hit. I went to dump the bottles and that when I noticed something. The bottled beer tasted pretty good. Still an off flavour but better.
So I dropped a cup of dextrose into the keg and let it sit in the closet for a couple of weeks. The result: Delicious bitter that I am still drinking on tap.