| Author |
Message |
   
Leland Dunn
Junior Member Username: Doonshiner
Post Number: 46 Registered: 09-2002
| | Posted on Tuesday, July 20, 2004 - 10:22 pm: |
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Last year I had this off flavor in about 4 batches in a row. It was like an extreme grapefruit kinda estery taste to the beer. It taste almost like it has about 1/4 grapefruit juice added to the beer. It became very frustrating because I didn't know what it was caused from. I narrowed it down to 3 things that I had changed just in those last 4 batches. One was I had changed to 10 gallon batches using a converted sanke for my boiling kettle, so I thought that maybe the flavors were in the keg. Secondly I had been using Wyeast Yeast Nutrient because when I went to the 10 gallon batches I was doing just partial mashes and adding the rest with DME. And finally I thought maybe my fermentation temps were too high. Well I went back to the 5 gallon batches using the older equipment as well as cutting out the yeast nutrient and fermenting at lower temps. The flavor went away. I was making some great brews through the winter. But since then I have moved back up to 10 gallon batches using a nicer converted keg. I didn't get any off flavors the first couple of batches, but I also didn't use the yeast nutrient, until my last batch of IPA. I put in a teaspoon and a half because I added about 9 lbs. of DME. I just tasted the beer into the secondary today and both carboys had the off flavor. One was fermented at 68 degrees constant while the other was about 70-72 degrees using White Labs Califonia Ale yeast (WLP 001). Can you get a grapefruit flavor from high fermentation temps? I know you can get esters but this seems different. I was just wondering if anybody had any experience with having off flavors from a yeast nutrient or what other possibilities this might be. |
   
Brandon Dachel
Senior Member Username: Brandon
Post Number: 1123 Registered: 03-2002
| | Posted on Tuesday, July 20, 2004 - 10:26 pm: |
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My only experience with yeast nutrient was years ago and not in beer-making, but mead making. I could have sworn that the few batches I used this stuff on ended up like rocket fuel, but realistically, I didn't really know what I was doing back then. |
   
Chumley
Senior Member Username: Chumley
Post Number: 2089 Registered: 02-2003
| | Posted on Wednesday, July 21, 2004 - 03:42 am: |
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Well, when one complains about grapefruit flavor, one imediately suspects "C" hops, primarily Cascades. What sort of beer have these batches been? |
   
Fredrik
Senior Member Username: Fredrik
Post Number: 1403 Registered: 03-2003
| | Posted on Wednesday, July 21, 2004 - 06:02 am: |
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I have no experience with this, but in case Chumley's hopidea isn't it, fwiw, a wild speculation would be that it's maybe some sulphur compound. I have seen many tiols are often descrived as citrousy/fruity. I am not sure exactly how there are formed, but I'd expect overpitching and also possible too high sulphur levels in the wort. Maybe even sulphur containing amin acids. What pitching rate did you use? Did you try without the nutrition? I'd think DME has enough nutritions in it as is. /Fredrik |
   
Magnus Graham
Member Username: Cellarman
Post Number: 166 Registered: 03-2003
| | Posted on Wednesday, July 21, 2004 - 11:44 am: |
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What is in yeast nutrient? |
   
Fredrik
Senior Member Username: Fredrik
Post Number: 1405 Registered: 03-2003
| | Posted on Wednesday, July 21, 2004 - 12:23 pm: |
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I don't know for sure but wyeast desribes their nutritient like this: "Wyeast nutrient is a blend of vitamins, minerals, amino acids, free amino nitrogen compounds, zinc, phosphates, and other trace elements beneficial for rapid and complete, fermentation." But I have looked at wyeast nutritients under my microscope and found that it contains plenty of dead cells of all kinds of shapes: round, rods, ellipsoids but of similar order of magnitude in size, like brewing yeasts. Also it stinks ammonia. So I suspect dead yeast cells of more than one kind judging from the diversity of shapes + maybe ammonium phosphate or something and possibly some extra mineral salts? Since then, I'm not going to buy more of that blend. It seems expensive to pay so much for just dead yeast. Instead I've now bought alot of cheap expired windsor dry yeast from my LHBS to use for this purpose. My LHBS put expired stuff on sale instead of throwing it away, which is nice. Ammonium salts can be purchased separately much cheaper. Perhaps there are something more in there though. /Fredrik |
   
Denny Conn
Senior Member Username: Denny
Post Number: 3207 Registered: 01-2001
| | Posted on Wednesday, July 21, 2004 - 04:46 pm: |
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I haven't ever experienced anything like that when I've used nutrient. LIfe begins at 60...1.060, that is.
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Leland Dunn
Junior Member Username: Doonshiner
Post Number: 47 Registered: 09-2002
| | Posted on Wednesday, July 21, 2004 - 07:26 pm: |
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I used some grapefruity hops (colombus, cascade, and simcoe) but this is an overpowering flavor. As far as the amount of yeast I had dumped it on a yeast cake from a previous batch so there was a full population of yeast ready for this IPA. I think that I am just going to have to wait a couple of weeks after secondary to see if it's still there. |
   
Fredrik
Senior Member Username: Fredrik
Post Number: 1409 Registered: 03-2003
| | Posted on Wednesday, July 21, 2004 - 07:36 pm: |
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I have no experience with neither those hops nor the strain, but just to continue my probably way off speculations as usual I'd consider dumping on a healthy yeast cake overpitching by a factor of 8-10. But in particular when overpitching like that, I don't see the point at all in adding yeast nutrition?? Even with a normal pitching rate it shouldn't be necessary unless you add sugar or something? I'm aware than many of people dump of yeast cakes w/o problem, but with some strains, *maybe* overpitching and also adding extra yeast nutrtition may squeeze forward obscene flavours? /Fredrik |
   
Denny Conn
Senior Member Username: Denny
Post Number: 3212 Registered: 01-2001
| | Posted on Wednesday, July 21, 2004 - 07:40 pm: |
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"with some strains, *maybe* overpitching and also adding extra yeast nutrtition may squeeze forward obscene flavours? "..I think I'd agree with this, but I can't explain how it would cause the particular flavors Leland's getting. LIfe begins at 60...1.060, that is.
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Chumley
Senior Member Username: Chumley
Post Number: 2096 Registered: 02-2003
| | Posted on Wednesday, July 21, 2004 - 07:52 pm: |
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Recently I tapped a keg of IPA where I used the SSoS recipe, subtituting 18.1% Columbus for Chinook. "Obscene grapfruit flavor" would be an adequate descriptor, but I like it.  |
   
Nick Zeigler
New Member Username: Ziggy
Post Number: 3 Registered: 09-2003
| | Posted on Thursday, July 22, 2004 - 07:19 pm: |
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Would it be ok to use sterlized slurry as nutrient or could that lead to off-flavors? |
   
Denny Conn
Senior Member Username: Denny
Post Number: 3221 Registered: 01-2001
| | Posted on Thursday, July 22, 2004 - 07:54 pm: |
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Nick, generally when old yeast is used as a nutrient, it's added to the boil. LIfe begins at 60...1.060, that is.
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Pam Phillips
New Member Username: Caskobsessed
Post Number: 8 Registered: 07-2004
| | Posted on Friday, July 23, 2004 - 12:42 am: |
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Maybe you're getting better hops utilization in the new equipment. Does the old kettle allow full volume boils? |
   
Leland Dunn
Junior Member Username: Doonshiner
Post Number: 48 Registered: 09-2002
| | Posted on Saturday, July 24, 2004 - 07:01 pm: |
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Yes, my converted sanke allows a full volume boil. But when I tasted the sample in transfer to the secondary it didn't taste all that bitter. Actually, I wish it was more bitter because I was really shooting for an aggressive IPA (1.069 O.G. 62 IBU's). I am just hoping that this will mellow out with time and maybe all of those colombus hops caused an extreme grapefuit explosion. |
   
Jared Cook
Intermediate Member Username: Jared
Post Number: 350 Registered: 09-2002
| | Posted on Saturday, July 24, 2004 - 09:00 pm: |
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The first, only, and last time I used columbus hops, I had the same "obscene grapefruit" flavor. Well, grapefruit mixed with a little cat piss. Can't say that I didn't screw up somewhere else because I was a partial boil extract brewer way back in those days (at least 6 years ago). I'll have to give them a try again sometime to see if I have the same opinion. |