Puzzled - hoppy ales - off flavor/aroma

I am running into a frustrating issue when brewing hoppy ales at home. I am getting a funky/sweet aroma that is reminiscent of bad breath.

It is nothing I have run into before. This aroma is noticeable in the finished product and has been occasionally recorded as far forward as the first day of two of primary fermentation. The aroma (which also shows up a bit in the flavor) has been consistent with the hoppy beers that I make. The hoppier the beer, the more pronounced the aroma/flavor. It also seems to be independent of the types of hops that I use and the types of yeast.

Here are some known variables:

Fermentation temp is rather consistent between 66-70F.
The ales that have displayed this trait so far have used either WLP001, WLP028, SafAle 04 or SafAle 05.
Primary fermentation has been between 5-7days.
OG has been in the 1.067-1.082 range (definitely an estimate).
IBUs have been in the range of 40-78. (ales below 40 have not shown this off-flavor/aroma).
Mash saccrification temps have varied. (all one-step)
I mash in a home-made cooler with a manifold/filter made from the wire mesh from a washing machine tube.
My kettle is 12gal, and to the best of my knowledge, is not stainless.
Primary and secondary fermenters are glass.
I am kegging and force carbonating my ales after time in secondary fermentation.

I have been brewing for a few years now and this is very frustrating to me that I cannot make a highly-hopped ale without the hop flavor and aroma going sour.

I hope someone out there has some incite or at least that I challenged some brewers out there to a new puzzle. Any advise would be appreciated. Keep doing what you all do best and have a hoppy homebrew for me.

Thanks in advance!
Brad

This is a very tough one to do, especially without being able to sample the brews in question.  But a couple of thoughts.

you mention a "funky/sweet aroma that is reminiscent of bad breath".  This COULD come from old hops. How were they stored?  Any just purchased hops from a different source? Perhaps unlikely since you say this occurs with all hops.

At the end you say "the hop flavor and aroma going sour".  The word "sour" is what jumps at me.  I'm not sure if you are refering to an aroma flavor characteristic or the fact the the beer has something "off" in it as you previously described.  If "sour" possibly an infection lurking in your transfer mechanism (pump or racting cane, hoses etc.)

Fred

SFBeerGuy said:

funky/sweet aroma that is reminiscent of bad breath.... first day of two of primary fermentation.  aroma has been consistent with hoppy beers. The hoppier the beer, the more pronounced the aroma/flavor. It also seems to be independent of the types of hops that I use and the types of yeast.

Fermentation temp is rather consistent between 66-70F.  {should be ok ==> no esters}
The ales that have displayed this trait so far have used either WLP001, WLP028, SafAle 04 or SafAle 05.  {not a single weird strain or yeast gone bad}
Primary fermentation has been between 5-7days.  {Q:  do you rack after 6-7 days??}

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funky/sweet/sour..........I've heard old stale hop flavors described as "cheesy" and experienced it once.  Given the above, I would agree with Fred, esp. since the hoppier the beer, the more pronounced the aroma/flavor.  Seems logical if the hops are aged or just poorly stored, the more you use the worse it gets.      Some hop varieties have pitiful storage characteristics.  And just to rule out sanitation issues, soak everything in hot PBW or Oxyclean, and then a sanitizer, fully broken down?  Replace anything you doubt?

One process question....you say primary ferms of 5-7 days.  If you are racking the beer to secondary on day 6-7, you may not be allowing the yeast time to clean up the fermentation by-products, including diacetyl among others.  If you do consistently rack off that quickly, you may have some combination of ferm by-products mixed with oldish hops.  If that is the case, allow a ferm to go at least 14 days to fully finish and clean up before moving it. 

bonjour said:

At the end you say "the hop flavor and aroma going sour".  The word "sour" is what jumps at me.  I'm not sure if you are refering to an aroma flavor characteristic or the fact the the beer has something "off" in it as you previously described.  If "sour" possibly an infection lurking in your transfer mechanism (pump or racting cane, hoses etc.)

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I use the word 'sour' for lack of a better word.  I simple meant 'bad.'  I did not mean to imply a souring of the beer.

bonjour said:

you mention a "funky/sweet aroma that is reminiscent of bad breath".  This COULD come from old hops. How were they stored?  Any just purchased hops from a different source? Perhaps unlikely since you say this occurs with all hops.

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The hops that I use all come from my local brew store here in San Francisco - SFBrewCraft.  Great store.  They either get prepackaged, nitrogen-flushed bags form a third party or in bulk and then weigh them out into 1oz bags to reseal.

The hops I use are not old and are kept in the freezer if I buy them a couple of days ahead of the brew.

Sanitation might be an issue but I doubt it. (doesn't mean to rule it out)  I do brew in my garage, but my friend does too and none of his beers have displayed this characteristic.  To be fair, he does not like hoppy beers at all and only brews Belgian styles.

I really appreciate your responses and please don't hesitate to post if you come up with anything else.  I will be checking these forums frequently.

Thanks again,
Brad

MaltLicker said:

SFBeerGuy said:

Fermentation temp is rather consistent between 66-70F.  {should be ok ==> no esters}
The ales that have displayed this trait so far have used either WLP001, WLP028, SafAle 04 or SafAle 05.  {not a single weird strain or yeast gone bad}
Primary fermentation has been between 5-7days.  {Q:  do you rack after 6-7 days??}

Click to expand...

One process question....you say primary ferms of 5-7 days.  If you are racking the beer to secondary on day 6-7, you may not be allowing the yeast time to clean up the fermentation by-products, including diacetyl among others.  If you do consistently rack off that quickly, you may have some combination of ferm by-products mixed with oldish hops.  If that is the case, allow a ferm to go at least 14 days to fully finish and clean up before moving it. 

Click to expand...

Good catch, these beers are just big enough that the yeast may not be cleaning up after themselves.  Keep them in the primary for a min of 2 weeks.  and from what you are describing you don't "need" a secondary.  Leave in the primary until clear then rack directly into a keg.

Fred

bonjour said:

MaltLicker said:

SFBeerGuy said:

Fermentation temp is rather consistent between 66-70F.  {should be ok ==> no esters}
The ales that have displayed this trait so far have used either WLP001, WLP028, SafAle 04 or SafAle 05.  {not a single weird strain or yeast gone bad}
Primary fermentation has been between 5-7days.  {Q:  do you rack after 6-7 days??}

Click to expand...

One process question....you say primary ferms of 5-7 days.  If you are racking the beer to secondary on day 6-7, you may not be allowing the yeast time to clean up the fermentation by-products, including diacetyl among others.  If you do consistently rack off that quickly, you may have some combination of ferm by-products mixed with oldish hops.  If that is the case, allow a ferm to go at least 14 days to fully finish and clean up before moving it. 

Click to expand...

Good catch, these beers are just big enough that the yeast may not be cleaning up after themselves.  Keep them in the primary for a min of 2 weeks.  and from what you are describing you don't "need" a secondary.  Leave in the primary until clear then rack directly into a keg.

Fred

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I'll give this a try.  I'm at my wit's end.  Why do you say that "these beers are just big enough that the yeast may not be cleaning up after themselves..."?

1. You are holding a good ferment temp, so your ferments will be a touch slower than many brewers.
2. The stronger the beer the more fermentables, the longer the ferment time.
3. 1 week is usually adequate for beers under 1.050 OG

It occurs to me that you may be detecting sulfur, not the common H2S.  I'm focusing on the "bad-breath"

The by-products that are produced (and also be metabolized) by the yeast are esters, fusel alcohols, diacetyl, and sulfur compounds. Esters are produced by yeast combining an organic alcohol and acid. While approximately 90 different esters have been identified in beer, ethyl-acetate, isoamyl-acetate and ethylhexanoate are most commonly above their flavor thresholds. These impart a fruity, sweet aroma to the beer. Another by-product of fermentation is fusel alcohols, which contain more carbon atoms than the most common alcohol, ethanol. These are produced by the metabolism of amino acids (4), and tend to add harsher, more solvent-like tones the beer. Yet another by- product is diacetyl, which is generally reduced to more benign compounds during the secondary fermentation, but premature removal of the yeast can lead to elevated levels. Its presence imparts a buttery note to the beer. It is produced by an oxidation reaction which can be repressed by the production of the amino acid valine (5). Lastly, there are several sulfur compounds that can be produced by the yeast. One of these is hydrogen sulfide, which smells like rotten eggs. Other sulfur compounds exist, but their production is not yet completely understood (1).

Sulfury/Yeasty

These flavors, not to be confused with DMS, have the aroma and taste of rotten eggs, shrimp or rubber. The compounds responsible for these flavors originate from sulfur-containing amino acids such as cysteine and methionine. Possible sources include yeast autolysis, bacterial spoilage and water contamination. These flavors can be quite putrid and are not desirable in any style. In the same family are sulfitic flavors, which recall the aroma of a struck match. They are usually due to the overuse of antioxidants, and while rare in beer, are quite common in wine and cider.

SFBeerGuy said:

OG has been in the 1.067-1.082 range (definitely an estimate).
IBUs have been in the range of 40-78. (ales below 40 have not shown this off-flavor/aroma).

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Yea, I assume your hops level scales directly with the OG, so perhaps your lower OG beers are finishing out cleaner than the higher OG beers.  So, for the WLPs, Do you make a yeast starter?  For the dry, do you rehydrate per instructions?  These OGs are also high enough that ensuring you're pitching enough healthy viable yeast is important.  Are your FGs getting down where you want/expect? 

As to the bulk hops in the store, I quit buying hops stored in bulk in a fridge at our LHBS.  There should be a quality or lifespan difference between 45F and exposed to air versus nitro-purged and kept at 0F in a freezer.  You could buy pounds direct, and split amongst friends. 

bonjour said:

It occurs to me that you may be detecting sulfur, not the common H2S.  I'm focusing on the "bad-breath"

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First of all, I appreciate the response and its technicality.  I don't think I am smelling sulfur as I am familiar with its aroma.  My friend is continually brewing Belgian (and sometimes English) style ales in my garage which tend to put off the recognizable sulfur smells towards the end of their fermentation and at higher temperatures.  I am however intrigued with the observation made by MaltLicker that the OG of my beers has a direct correlation with their IBUs.  This is not always the case but worth looking into.  I think I will attempt a basic IPA of lower gravity (1.058 or so) and keep it heavily hopped to see what sort of results I can get.

Also, to answer MaltLicker's other questions pertaining to the yeast for these brews: I usually make starters two days prior to the brew with White Labs or Wyeast liquid yeast.  A few times I have used SafAle dry yeast and did not make starters with them.  I do not think the dry yeast issue is the source of the problem as I have successfully made great beers with SafAle yeast pitched straight from the packet.

Another opinion that I have received about this issue had to do with ethyl-alcohols and fermentation conditions.  I am currently thinking that maybe I am experiencing some sort alcohol by-product problem that is being accentuated by essential hop oils or iso-a-acids.  The beer I make is good but by NO MEANS professional quality.  That is what I am working towards and that is what UC Davis will teach me in 2011.

Thanks again guys.  The wealth of knowledge in these forums is astounding!
Keep doing what you do best, and anything else pertaining to this issue will be appreciated.
Brad

ps - Has anyone heard of non-stainless steel pots leaching metal ions or changing any of the conditions of boiling wort?

ps - Has anyone heard of non-stainless steel pots leaching metal ions or changing any of the conditions of boiling wort?

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This is a very well documented and highly debated MYTH. IMO... Use Aluminum, Stainless, Steel, Pyrex or what ever.

Cheers
Preston

SFBeerGuy said:

A few times I have used SafAle dry yeast and did not make starters with them.  I have successfully made great beers with SafAle yeast pitched straight from the packet.

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I re-learned recently that dry yeast has ~20 billion cells per gram, so approx. 200 billion cells in a 10 or 11 gram package, assuming it is properly re-hydrated. 

The yeast mfrs guarantee only 6.9 billion cells b/c they assume home brewers are just sprinkling yeast on top of the wort.  That means a typical dry yeast might have 30% less viable yeast than a typical liquid yeast of 100 billion cells.  And no comparison if you're usually making starters from liquid yeasts.  You could triple the dry yeast count (that you've already paid for) by re-hydrating it before pitching. 

UselessBrewing said:

This is a very well documented and highly debated MYTH. IMO... Use Aluminum, Stainless, Steel, Pyrex or what ever.

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What have you heard?  Anything pertaining to hop flavor or aroma?  Anything about pH?

SFBeerGuy said:

bonjour said:

It occurs to me that you may be detecting sulfur, not the common H2S.  I'm focusing on the "bad-breath"

Click to expand...

First of all, I appreciate the response and its technicality.  I don't think I am smelling sulfur as I am familiar with its aroma.  My friend is continually brewing Belgian (and sometimes English) style ales in my garage which tend to put off the recognizable sulfur smells towards the end of their fermentation and at higher temperatures. 

Click to expand...

These aromas would be either DMS or Hydrogen Sulfide, and I never thought they would be there and I was sure you would have identified them.  I was looking at the Other in sulfur as possibilities.

What are the possibility of oxidation being a factor?  How do you rack from primary to secondary and from secondary to to keg.  I assume all these beers are kegged beers, if you bottle how do you bottle.  What tools/equipment do you use for racking?

You also stated that the higher hopped beers have a more pronounced off-flavor.  Any Flourescent or sun-light exposure?  Do you cover your glass fermenters?  Lightstruck is one off-flavor that becomes more pronounced in hoppier beers.  Sulphur is involved in this as well.

What have you heard?  Anything pertaining to hop flavor or aroma?  Anything about pH?

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Nothing about Hop flavors or PH that I can recall. Mostly it is about leaching metals into the wort, and causing Alzheimer's. There may be some leaching of metals, but any links to Alzheimer is false. In the early 60's a doctor found traces of aluminum in a patients brain tissue which lead him to believe there was a link. Later this was disproved because not all Alzheimer patients had traces of aluminum in the brain tissue. This debate still shows up in all the forums.

Here is a link to some good info
http://www.webmd.com/alzheimers/guide/controversial-claims-risk-factors

Cheers
Preston

I've seen strong arguments both ways...........the acidity and heat leaching aluminum off the pot into the wort ==> bad.........versus, we get more of that same effect from the aluminum oxide coating on most teflon pots, and we get traces of aluminum from many multi-vitamins.  Your mileage may vary. 

If you clean an Al pot til it's shinny, removing the oxide layer, you could get some flavor contribution but I don't recall what that flavor contribution would be.

Exposed Iron, carbon steel, such as from a chipped enamel pot can cause a metallic flavor "such as sucking on a penny"

SFBeerGuy said:

bonjour said:

It occurs to me that you may be detecting sulfur, not the common H2S.  I'm focusing on the "bad-breath"

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What are the possibility of oxidation being a factor?  How do you rack from primary to secondary and from secondary to to keg.  I assume all these beers are kegged beers, if you bottle how do you bottle.  What tools/equipment do you use for racking?

You also stated that the higher hopped beers have a more pronounced off-flavor.  Any Flourescent or sun-light exposure?  Do you cover your glass fermenters?  Lightstruck is one off-flavor that becomes more pronounced in hoppier beers.  Sulphur is involved in this as well.

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My beers are kegged.  I do not think that oxidation is a factor.  I am rather careful when racking to avoid splashing.  

I do have a fluorescent light in my garage but my beers are wrapped in a towel while fermenting if they are not put in the chest freezer.  How sensitive are hop oils and acids to UV light?  I am sure that while checking on a beer they are exposed for short periods of time to low wattage commercial fluorescent tube lights.

Beers can skunk in sunlight in as little as 30 seconds, but it sounds like you are ok there.

Try and skip the secondary on one brew, and but CO2 on the bottom of the keg before racking and do not rack with an auto-siphon and make sure no bubbles in your siphon line.  Despite the fact you say, and I do believe you, that you rack with care I still see some room for oxidation to occur.

bonjour said:

Put CO2 on the bottom of the keg before racking and do not rack with an auto-siphon and make sure no bubbles in your siphon line.

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Ditto on the CO2 purge.  Doesn't take much to get a protective layer on bottom of the carboy or bucket.  

I've never had an auto-siphon b/c the guy that taught me had one of these bulb priming pumps.  Easy to sanitize, use and store, it works.  Also handy for pushing sanitizer through your hoses to ensure 100% coverage.   ($5 at WMT in the fishing supplies. It's made to prime a boat engine.)

First of all I want to thank you all for sharing your knowledge with me.  I do agree that with my current setup at home that I could probably be doing a better job combating oxidation in my brews.  With that said, I am still skeptical that it is oxidation which is causing my problems. 

Personally, I think that it is a compound issue having to do with my equipment and procedure.  I am going to try a low-gravity IPA this Saturday and see if it has anything to do with the IBU/OG ratio.

I will post again in the future, letting you all know if I have had any luck.  In the mean time, wish me luck and keep brewing that beer!