Off flavors

Would you describe the vegetable as similar to creamed corn and/or cabbage? If not, how would you describe it?

 

“a little turned vegetable”

That description has me wondering whether there is perceptible DMS (Dimethyl sulfide) in your beer. DMS is often described as providing a corn (creamed corn) like flavor but depending upon the amount of DMS and an individual’s palate it could also present itself as a vegetal flavor.

It is a best practice to conduct a vigorous boil to evaporate/drive off DMS.

It is also a best practice as regards DMS to have a quick cooling of the wort since the precursor of DMS – SMM (S-methylmethionine) is still present in the boiled wort and an extended hot time post boil will permit that SMM to convert to DMS.

Can you please provide more details about your brewing process? How vigorous is your boil? How quickly do you cool down the wort post boil?

Cheers!

 

A 75min boil, even a soft one, should be sufficient. If you do end up diagnosing this as DMS, that could be the issue, I guess.

I have tasted a vegatal off-flavor before that is decidedly NOT DMS. It has been alternately described as peachy, melon, or raw pumpkin. It is almost always a sign of fermentation stress. Often temperature swings or under-pitch/unhealthy yeast. I’d say your yeast might be the culprit.

 

So it could be DMS. Though I agree with @JohnnyChicago that even a soft boil for 75 minutes should usually be sufficient for typical 2-row malt.

Regarding the "esters," all three of the hop varieties you used can bring fruity aromas/flavors, so that may be a factor.

 

Was the yeast past it's date, or do you remember the packet being compromised in any way?

 

From my experience, DMS is not a very common off-flavor unless the brewer is using a very low modification Pilsner malt or intentionally trying to get it. I would bet that it is more likely stale caramel malt or even a little diacetyl that is not being described accurately. Maybe wait for a little more carbonation

 

This is one of the reasons I only use liquid yeast. In theory, there should be no difference, but my experience having worked at a LHBS has shown that dry yeast often gets treated much rougher than liquid. We would often get the shipment unrefrigerated, which could get over 100° in a box truck in the summer. Who knows what other abuse it’s been subjected to? There is literally no way to know.

That’s the nice thing about liquid packets. They will start to swell when they are old or haven’t been kept well. It’s a nice little failsafe.

 

Like keeping an extra sachet or 2 of US-05 on hand for when the summer shipment of liquid yeast arrives.

 

I have used US-05 a lot and I have never experienced any fermentation issues with this product. I attended a presentation at NHC-2015 on the topic of Selecting Yeast by Kevin Lane of Fermentis. Kevin stated that for the dry yeasts of Fermentis you will lose 5% viability over 1 year in refrigerated conditions and 10% viability loss of 1 year at room temperature. Dry yeast is much more robust than liquid yeast from a viability loss perspective over time/temperature.

Cheers!

 

No doubt it is much more robust. And more efficient! Many a delicious brew was made from a room temperature Brewer’s Best kit with the yeast packet taped to the box.

But another way to interpret that data is that a 30° increase results in a 100% decrease in viability. I’m not so worried about the time spent on the floor in an air conditioned LHBS, but rather, the weeks spent over 100° in a warehouse, truck, or shipping crate.

Just one of those things that works differently for different brewers. I always had consistency issues when I used dry yeast. Switched and they went away. My system must just like liquid...

 

And I have brewed 100+ batches with dry yeast and I have experienced zero consistency issues.

The utility of a discussion forum is that differing experiences can be discussed/presented.

I will be brewing a Saison tomorrow using dry yeast from Fermentis and if my past 100+ experiences are an indicator this fermentation will go well with zero issues.

Cheers!

 

Vegetables obviously sets off the DMS alarm bell, but has anyone ever tasted DMS in homebrew? I never tasted it in mine and I've done a bunch of home brew judging without ever tasting it in any homebrew. In fact, the only beers I've ever tasted it in are Rolling Rock and a batch of Oktoberfest at my last brewery.

 

I wonder if they were brewed with the same base Pilsner malt?

edit: RR might have some 6 row?