Diacetyl Woes (Advice Please?)

[Wayne1]

Pro Brewers use ALDC at yeast pitch to prevent the precursors from forming. https://bsgcraftbrewing.com/Content/Images/uploaded/ALDC onesheet_web.pdf

 

[Coffeeturnal]

That sounds like a very useful product. Do you know if it's available on a homebrew level?

Pro Brewers use ALDC at yeast pitch to prevent the precursors from forming. https://bsgcraftbrewing.com/Content/Images/uploaded/ALDC onesheet_web.pdf

 

[IslandLizard]

Make sure the yeast starters were made properly and yeast is always pitched within 10F of wort temps (5F is even better). This is to prevent forming of petite mutants that cannot metabolize diacetyl, and may be a possible indication of stalled fermentations, especially in higher gravity beers.

I've read Conan strains can be finicky, so I'd definitely switch to another yeast to compare. Do you oxygenate your wort?

Although cleaning and sanitation were mentioned before, to eliminate another source of Pedio from the equation, pay some extra attention to cleaning and sanitizing valves and seals on your equipment, even the ones on your boil kettle.

Take the valves apart and clean and sanitize thoroughly, especially the spaces behind the ball. Over time a black sludge can develop in there loaded with Pedio. Even a gas heat source doesn't seem to get that valve area on a kettle hot enough to kill them. I take them apart around every 6-8 brews. I've only found the black slime in a 2-part kettle valve I had been using for 2-3 years and earlier inside my bottling bucket's spigot before I started kegging the majority of my beer. In those, the slime harbors in the narrow space between the two 3/4" plastic barrels that rotate within each other, and behind the rubber seals between the body and bucket, as well as in the threads.

 

[Wayne1]

That sounds like a very useful product. Do you know if it's available on a homebrew level?

To the best of my knowledge, it is available from Brewers Supply Group in the US. It is sold in a liter container. Gusmer also sells ALDC but in a minimum of 5 kilograms.

Perhaps some homebrew shop could purchase the liter container and repackage it in smaller quantities for homebrew use.

 

[ScrewyBrewer]

For those of you that are cold crashing, are you able to maintain positive head pressure with Co2 when doing so? Otherwise you’re just asking for a ton of O2 pickup which can cause all sorts of issues, especially with hoppy beers.

Fermenting 10 gallons of Amber Ale in a chest freezer for a week fills it with plenty of nostril burning Co2. More than enough to kill off any fruit flies that found their way inside it. I'm not worried at all about introducing O2 during cold crashing.

 

[Northern_Brewer]

Pro Brewers use ALDC at yeast pitch to prevent the precursors from forming. https://bsgcraftbrewing.com/Content/Images/uploaded/ALDC onesheet_web.pdf

I'd view ALDC as a last resort to clean up the last traces - and it tends not to be easily available in retail packs. So for instance Cloudwater use it, but they obsess over yeast health with eg zinc and nutrients, and start the diacetyl rest for their DIPA at 1.045 - see this blog (and other articles there), and the recipe linked therein.

 

[poley]

Aggressive dry hoppping can cause refermentation due to the enzymes present in hops. If you're doing a large dry hop addition, try adding it while you still have yeast in suspension to quickly chew up the new fermentables created from the enzymes in your hops. If you do not allow your fermentation to fully ferment out those new sugars, you could have bottle bombs. If you see fermentation kick back up, based on hydrometer readings, make sure you check for diacetyl again before crashing and packaging.

For more info, do some research on "dry hop creep".