eddyfice
Member
Hi,
I started homebrewing a short while back and have some questions regarding Diacetyl production, in your experience, as sources I had read seemed to conflict (although right now I cannot remember where such sources were -- blame the pint of ale sitting in front of me).
In short, this boils down to a few questions:
1. Does diacetyl production relate to the temperature of the primary fermentation (e.g. the fermentation performed in the primary vessel, which takes around 4-5 days for my setup/temperature).
1.a. Is 24C too high a temperature for Cooper's Ale Yeast? I have been led to believe that this yeast is generally less prone to producing such off-flavors at higher temperatures. My kitchen (throughout my homebrewing "career") has sat stubbornly at a near-constant 24C.
2. I have read of leaving the primary fermentation vessel alone for several days after the primary fermentation is complete (airlock stops bubbling, gravity remains constant) in order to perform a "diacetyl rest", but similarly I have read that such a rest should not take very long at the temperatures I am brewing.
I should note that I am near-religious with my cleanliness (blame OCD); I first clean + scrub (glassware), then sanitise using sanibrew, and use a closed fermentation method. Therefore I would be extremely surprised if this was a Lactobacillus-infection causing the diacetyl production. Literally everything that comes in contact with the wort or gas in contact with the wort is cleaned like this.
Should I just go and buy myself a refrigerator and a temperature controller already? I could just wait for the winter to roll around for half of these questions to be answered empirically, but I'm dying for someone to enlighten me sooner than that
I should note that in the last two batches, the popcorn butter + apple tones (diacetyl and acetaldehyde respectively) were greatly reduced by raising the quantity of DME to above the levels of Dextrose I was employing; a ratio of 1:1 (500g MDME, 500g DDME, 1000g dextrose, + Coopers Dark Ale Kit).
I come from the UK and I miss my ale; help make a poor expat happy and tell me how to stop my beer tasting like someone dropped their popcorn in it!
Thanks in advance.
I started homebrewing a short while back and have some questions regarding Diacetyl production, in your experience, as sources I had read seemed to conflict (although right now I cannot remember where such sources were -- blame the pint of ale sitting in front of me).
In short, this boils down to a few questions:
1. Does diacetyl production relate to the temperature of the primary fermentation (e.g. the fermentation performed in the primary vessel, which takes around 4-5 days for my setup/temperature).
1.a. Is 24C too high a temperature for Cooper's Ale Yeast? I have been led to believe that this yeast is generally less prone to producing such off-flavors at higher temperatures. My kitchen (throughout my homebrewing "career") has sat stubbornly at a near-constant 24C.
2. I have read of leaving the primary fermentation vessel alone for several days after the primary fermentation is complete (airlock stops bubbling, gravity remains constant) in order to perform a "diacetyl rest", but similarly I have read that such a rest should not take very long at the temperatures I am brewing.
I should note that I am near-religious with my cleanliness (blame OCD); I first clean + scrub (glassware), then sanitise using sanibrew, and use a closed fermentation method. Therefore I would be extremely surprised if this was a Lactobacillus-infection causing the diacetyl production. Literally everything that comes in contact with the wort or gas in contact with the wort is cleaned like this.
Should I just go and buy myself a refrigerator and a temperature controller already? I could just wait for the winter to roll around for half of these questions to be answered empirically, but I'm dying for someone to enlighten me sooner than that
I should note that in the last two batches, the popcorn butter + apple tones (diacetyl and acetaldehyde respectively) were greatly reduced by raising the quantity of DME to above the levels of Dextrose I was employing; a ratio of 1:1 (500g MDME, 500g DDME, 1000g dextrose, + Coopers Dark Ale Kit).
I come from the UK and I miss my ale; help make a poor expat happy and tell me how to stop my beer tasting like someone dropped their popcorn in it!
Thanks in advance.