Hey Everyone! I am new to BeerAdvocate and to Home brewing. I have a couple of questions I am curious about. Three days ago I tried my first homebrew. A clone of Pliny the Elder. I know, start simple and you can’t screw it up. I drink double IPA’s, so it’s go big or go home at my house. But All is well, I think!?! Three days into fermentation and I am mesmerized every time I check the glass carboy. The swirling and activity that is going on in this thing is crazy. Can anyone explain to me what I am seeing inside the carboy during primary fermentation? It appears that there is motion coming from the trub at the bottom as well as from the top yeast cake. Are they gas bubbles? They don’t look like a gas. But it has me curious! Any help would be appreciated.
A by-product of the fermentation process is CO2 production; you should be noticing the CO2 bubbling out through your airlock. If you are into biochemistry this is what is going on: Cheers!
Jack Thank you. That is exactly what I was looking for. It does beg the question (to the newbie brewer) how so different varieties of yeast affect this chemistry? Are some just more efficient? Or are some yeast strains better suited for the conditions of different worts?
It's just yeast swirling around. I, too, think it to be mesmerizing, but it's nothing out of the ordinary.
This basic chemistry is the same for fermentation, in general. What makes different genera, species, and strains of yeast different is enzymatic potential. As strictly applied to fermentation, it depends on which enzymes are present to break down the different carbon sources (types of sugar) so that they can enter the cycle above as glucose. And, yes, wort composition also makes a difference. If you would like a more thorough explanation, I can certainly direct you to some more advanced reading, if you like, as such an explanation is not well-suited to a message board such as this.
You’re looking at magic. Pure, unadulterated, beer-making magic. Enjoy it, my brother, and know that I too am staring at my carboy, enthralled by the mystic churning generation of beer. (Maybe I’ve had a beer or two already tonight )
I appreciate the insight. I would absolutely like to do some more reading on fermentation processes. Besides, if this batch comes out not so pleasing, I’d like to know where I went wrong.
Part of it is the CO2 production, also involved is the movement of molecules due to temperature. In the center of the carboy the fermentation is warmer and moves the liquid upward as such. It then rolls out towards the sides where it is cooler and drops towards the bottom. This all creates convection. What you see is the liquid moving about with larger yeast collections. At times you will see it swirl as the rising and dropping liquids converge. Simply put, it looks really cool.
The basic biochemistry is common. Well, some yeast strains will attenuate more (i.e., a lower final gravity) than others but I would not use the word "efficient" to describe this aspect. It really comes down to what you are trying to achieve for a specific batch of beer. That really is a broader question. I would suggest that yeast strain selection is 'better' related to a beer style selection and you would be best served to create a wort suited for that beer style as well. Cheers!
While I enjoy the science behind brewing, part of it is magic. I have always been intrigued with the witches around the cauldron imagery along with the elemental aspects (water, earth, fire) of brewing.
It does look really cool. Here is a good question from the newbie. My kit came with one of those stick on thermostats for the side of the carboy. I put it on the side because it’s the best I could do. It’s staying pretty steady on the 68 degree mark. But that could mean it’s higher in the middle. Does anyone use a floating thermometer in the wort as it ferments or am I overthinking it?
I think that’s the best part for me too. I spent a good long time researching best practices and reading a few books. I had this image in my head that in the end it’s just a recipe and that the most important parts were keeping a sterile environment and not screwing up the yeast. And what really happened was a couple buddies and I sat around for an afternoon drinking and making are way through the recipe. We hit our specific gravity in our wort. It’s fermenting as it should be. And it looks like we should end up with beer at the end. That truly is witches cauldron magic!
We followed a clone kit for PtE from a local Homebrew store here in PA. They have been great in every aspect. Answering every question I have had. That being said, the yeast strain was given to us for that specific beer. It was Safale US-05, for a double IPA with an original gravity of 1.072, to get a final gravity of 1.011.
Stick on therm strips work fine. The center temp in a carboy is only a couple degrees higher than the ambient. I use a thermowell in my carboy that regulates from the middle and the therm strip is fairly close to my programmed temp.