Help me figure out this off-taste...

[crashlann]

A buddy of mine gave me a homebrew Saison today. It has a kind of toffeeish, molasses taste that is not intended. It also has a lot of bubblegum and banana. I have had this taste in several of my beers, most recently a Hef that I underpitched and fermented at 66F. My buddy's beer is drinkable, but Im pretty sure its not what he was shooting for. I have had similiar experiences...drinkable to me, but not something Im proud of. Any ideas? What part of the process seems to be the culprit? Thx.

[brewinhard]

If it was extract, then maybe it could be from using a not so fresh liquid extract. It could possibly also be from the beginning stages of oxidation or even some kettle caramelization. Just some thoughts, but it is hard to identify without tasting it myself. Hopefully some others will chime in too...

[Afterlab]

Can you provide a grain bill and process details for these beers?

Saison and Hefeweizen yeast are definitely Phenolic Off Flavor(+) yeast so it would make sense that phenols would be detected in those beers. Bubblegum is a yeast phenol that can come from just about any yeast with poor fermentation conditions. The banana flavor (Isoamyl Acetate) is an ester typically created by Hefeweizen and the Yorkshire yeasts. The creation of phenols and esters are dependent on too many fermentation and process variables to pinpoint what the cause is without knowing more about your process and recipes.

The only source of the toffee flavor in your friends saison that I can think of would be dark belgian candi sugar/syrup or using a higher lovibond crystal malt; which doesn't really belong in a traditional saison.

Are you doing yeast starters, using reputable cleaning and sanitizing agents, properly aerating and starting off with water that isn't saturated with chlorine?

[crashlann]

Can you provide a grain bill and process detals for these beers?

Saison and Hefeweizen yeast are definitely Phenolic Off Flavor(+) yeast so it would make sense that phenols would be detected in those beers. Bubblegum is a yeast phenol that can come from just about any yeast with poor fermentation conditions. The banana flavor (Isoamyl Acetate) is an ester typically created by Hefeweizen and the Yorkshire yeasts. The creation of phenols and esters are dependent on too many fermentation and process variables to pinpoint what the cause is without knowing more about your process and recipes.

The only source of the toffee flavor in your friends saison that I can think of would be dark belgian candi sugar/syrup or using a higher lovibond crystal malt; which doesn't really belong in a traditional saison.

Are you doing yeast starters, using reputable cleaning and sanitizing agents, properly aerating and starting off with water that isn't saturated with chlorine?

Yes, I am doing yeast starters based on Mr.Malty calculations, and I dont have any cleaning issues.
I do aerate at the time of transfer to the carboy, no chlorine issues.
Speaking for my beers, I have had this specific off flavor in several of my tripels and beers using Belgian yeast. Actually, now that I stopped doing stupid things like aerating the wort in the carboy on day 4-7 (duh...), it has gone away. I was doing extract beers primarily.
The taste I am trying to describe is not anything I have ever tasted in a commercial example of any of these beers, thats why I am describing it as an off flavor. I was hoping it was a common off flavor and it would be easy to identify with the group. If I get the flavor again, I will post the details and ask again...
Thanks for the great info as always, sorry I couldnt give more details at this time...

[Afterlab]

I dont have any cleaning issues.

Oddly enough when it comes to phenols, the question isn't necessary if you're cleaning and sanitizing but rather what you're cleaning and sanitizing with. Often times dish soaps and detergents (even the unscented ones) leave behind microscopic compounds in your kettle, racking equipment, carboys, bottles, etc... and a lot of these can mix with other natural beer compounds to create undesirable phenols and hazes in your beer.

I would say brew a straightforward pale ale or a blonde with Cal Ale yeast and see if those flavors show up. At this point it's difficult to tell if it's just the belgian yeast you've been using.