Recent Clove Off Flavor In Batches

[East_KentWood]

Hello All!

Very grateful for the information I've utilized in this forum. I recently signed up to seek occasional help beyond my local peers.

Recently, I've been getting a simular clove off flavor across a few beer styles and different fermentors. We're a new 7bbl brewery with many start up issues to be resolved and improved. But I'm leaning on HEX or aeration stone assembly being less than adequate cleaning SOP. Possibly, less likely, fermentation temp readings incorrectly low and fermenting too high.

Greatly appreciate any ideas.

[liammckenna]

What is your house strain of yeast?

[Weehe]

Yeast strain will play a big part. But if you are using a non-Belgian strain high fermenting temps and too much oxygen can cause that issue.

[UnFermentable]

"Clove" is most closely associated with 4-vinylguiaicol. It is a phenolic compound heavily influenced by ferulic acid content. Usually production is below the flavor threshold (about 200 ppb), however specific strains with a "POF" gene (Phenolic Off Flavor, now called PAD1+) will have excessive levels of 4-vinylguiaicol production. This includes some Belgian strains (as mentioned) however it also includes German wheat beer strains.

Yeast is a great question to address first, however mashing ingredients and regime can influence ferulic acid content and thus production of the 4-vinylguiaicol. Wild yeast or bacteria may be capable of producing this compound as well, so it is important to verify your CIP/SIP practices.

Pack for extended periods (6 hours+) with PAA solution at the end of SIP for an effective log reduction of most any of your concerns. Check compatibility with your gasket material first.