Ask The Brewmasters

Hello,

In the constant pursuit of quality improvement, I have noticed something about fermentor racking arm orientation during fermentation and would like to solicit outside opinions. I'll explain, and then ask the question.

Our SOP is to orient the racking arm slightly downward (in a 4-5 o'clock position) before filling the fermentor. From there, fermentation and cold conditioning proceeds as you'd normally expect. When it comes time to fine the finished beer, we will turn the racking arm upward so we are able to do a few brief bursts with CO2 through the racking arm in order to homogenize the fining agent in the beer. When rotating the racking arm upward from the 4-5 o' clock position, we will get a good bit of burping or bubbling due to a void that exists inside the racking arm since filling the fermentor (imagine holding a cup upside down and submerging it in a liquid, where a void exists inside the cup when the cup is submerged. You tilt the cup, and the void fills with the liquid, displacing the gas inside).

With this in mind, here is my question: Is it possible that we are oxidizing the finished beer when rotating the racking arm upward, as we are filling that void inside the racking arm with beer? Conversely, recognizing that the void in the racking arm would contain some amount of O2 at the start of fermentation, would the yeast consume the oxygen in the void, leaving only CO2 to subsequently escape when we rotate the racking arm upward at that fining step? Obviously, there is an interface between fermenting beer and the void in the racking arm, so perhaps the O2 in the arm is consumed during fermentation, and so when we rotate the racking arm as described above, we are only displacing CO2. We have our reasons for leaving the racking arm oriented the way we do prior to fermentation, but if this is causing us to subsequently oxidize the finished beer when we rotate the arm, we must consider modifying our SOP!

Thank you kindly for any insight.

Hey Travis, 

We currently point our racking arms in the same manner as you (more 6 o'clock position), and have also heard/felt that bubble make its way out of the racking arm as its rotated up in preparation to begin spinning it. We check our FV DO's immediately before centrifuge, at the centrifuge outlet, and periodically at the brite as it fills and we generally see +/- 5 ppb all the way through. I imagine if this bubble were indeed oxidative we would see larger spikes in DO along the way. I don't have an answer as to what this bubble actually is but I'm really curious to see what others out here think! 

Hello,

In the constant pursuit of quality improvement, I have noticed something about fermentor racking arm orientation during fermentation and would like to solicit outside opinions. I'll explain, and then ask the question.

Our SOP is to orient the racking arm slightly downward (in a 4-5 o'clock position) before filling the fermentor. From there, fermentation and cold conditioning proceeds as you'd normally expect. When it comes time to fine the finished beer, we will turn the racking arm upward so we are able to do a few brief bursts with CO2 through the racking arm in order to homogenize the fining agent in the beer. When rotating the racking arm upward from the 4-5 o' clock position, we will get a good bit of burping or bubbling due to a void that exists inside the racking arm since filling the fermentor (imagine holding a cup upside down and submerging it in a liquid, where a void exists inside the cup when the cup is submerged. You tilt the cup, and the void fills with the liquid, displacing the gas inside).

With this in mind, here is my question: Is it possible that we are oxidizing the finished beer when rotating the racking arm upward, as we are filling that void inside the racking arm with beer? Conversely, recognizing that the void in the racking arm would contain some amount of O2 at the start of fermentation, would the yeast consume the oxygen in the void, leaving only CO2 to subsequently escape when we rotate the racking arm upward at that fining step? Obviously, there is an interface between fermenting beer and the void in the racking arm, so perhaps the O2 in the arm is consumed during fermentation, and so when we rotate the racking arm as described above, we are only displacing CO2. We have our reasons for leaving the racking arm oriented the way we do prior to fermentation, but if this is causing us to subsequently oxidize the finished beer when we rotate the arm, we must consider modifying our SOP!

Thank you kindly for any insight.

Hello,

In the constant pursuit of quality improvement, I have noticed something about fermentor racking arm orientation during fermentation and would like to solicit outside opinions. I'll explain, and then ask the question.

Our SOP is to orient the racking arm slightly downward (in a 4-5 o'clock position) before filling the fermentor. From there, fermentation and cold conditioning proceeds as you'd normally expect. When it comes time to fine the finished beer, we will turn the racking arm upward so we are able to do a few brief bursts with CO2 through the racking arm in order to homogenize the fining agent in the beer. When rotating the racking arm upward from the 4-5 o' clock position, we will get a good bit of burping or bubbling due to a void that exists inside the racking arm since filling the fermentor (imagine holding a cup upside down and submerging it in a liquid, where a void exists inside the cup when the cup is submerged. You tilt the cup, and the void fills with the liquid, displacing the gas inside).

With this in mind, here is my question: Is it possible that we are oxidizing the finished beer when rotating the racking arm upward, as we are filling that void inside the racking arm with beer? Conversely, recognizing that the void in the racking arm would contain some amount of O2 at the start of fermentation, would the yeast consume the oxygen in the void, leaving only CO2 to subsequently escape when we rotate the racking arm upward at that fining step? Obviously, there is an interface between fermenting beer and the void in the racking arm, so perhaps the O2 in the arm is consumed during fermentation, and so when we rotate the racking arm as described above, we are only displacing CO2. We have our reasons for leaving the racking arm oriented the way we do prior to fermentation, but if this is causing us to subsequently oxidize the finished beer when we rotate the arm, we must consider modifying our SOP!

Thank you kindly for any insight.

I'm curious to know why folks would leave the racking arm down during fermentation, only to need to rotate it later for finings, and then I assume to rotate it back down for transfer to BBT? Why not just go through primary and finings (we do a recirculation) with the arm up, and rotate once for transfer to the brite?

Hello,

In the constant pursuit of quality improvement, I have noticed something about fermentor racking arm orientation during fermentation and would like to solicit outside opinions. I'll explain, and then ask the question.

Our SOP is to orient the racking arm slightly downward (in a 4-5 o'clock position) before filling the fermentor. From there, fermentation and cold conditioning proceeds as you'd normally expect. When it comes time to fine the finished beer, we will turn the racking arm upward so we are able to do a few brief bursts with CO2 through the racking arm in order to homogenize the fining agent in the beer. When rotating the racking arm upward from the 4-5 o' clock position, we will get a good bit of burping or bubbling due to a void that exists inside the racking arm since filling the fermentor (imagine holding a cup upside down and submerging it in a liquid, where a void exists inside the cup when the cup is submerged. You tilt the cup, and the void fills with the liquid, displacing the gas inside).

With this in mind, here is my question: Is it possible that we are oxidizing the finished beer when rotating the racking arm upward, as we are filling that void inside the racking arm with beer? Conversely, recognizing that the void in the racking arm would contain some amount of O2 at the start of fermentation, would the yeast consume the oxygen in the void, leaving only CO2 to subsequently escape when we rotate the racking arm upward at that fining step? Obviously, there is an interface between fermenting beer and the void in the racking arm, so perhaps the O2 in the arm is consumed during fermentation, and so when we rotate the racking arm as described above, we are only displacing CO2. We have our reasons for leaving the racking arm oriented the way we do prior to fermentation, but if this is causing us to subsequently oxidize the finished beer when we rotate the arm, we must consider modifying our SOP!

Thank you kindly for any insight.

Hello,

In the constant pursuit of quality improvement, I have noticed something about fermentor racking arm orientation during fermentation and would like to solicit outside opinions. I'll explain, and then ask the question.

Our SOP is to orient the racking arm slightly downward (in a 4-5 o'clock position) before filling the fermentor. From there, fermentation and cold conditioning proceeds as you'd normally expect. When it comes time to fine the finished beer, we will turn the racking arm upward so we are able to do a few brief bursts with CO2 through the racking arm in order to homogenize the fining agent in the beer. When rotating the racking arm upward from the 4-5 o' clock position, we will get a good bit of burping or bubbling due to a void that exists inside the racking arm since filling the fermentor (imagine holding a cup upside down and submerging it in a liquid, where a void exists inside the cup when the cup is submerged. You tilt the cup, and the void fills with the liquid, displacing the gas inside).

With this in mind, here is my question: Is it possible that we are oxidizing the finished beer when rotating the racking arm upward, as we are filling that void inside the racking arm with beer? Conversely, recognizing that the void in the racking arm would contain some amount of O2 at the start of fermentation, would the yeast consume the oxygen in the void, leaving only CO2 to subsequently escape when we rotate the racking arm upward at that fining step? Obviously, there is an interface between fermenting beer and the void in the racking arm, so perhaps the O2 in the arm is consumed during fermentation, and so when we rotate the racking arm as described above, we are only displacing CO2. We have our reasons for leaving the racking arm oriented the way we do prior to fermentation, but if this is causing us to subsequently oxidize the finished beer when we rotate the arm, we must consider modifying our SOP!

Thank you kindly for any insight.

Hello,

In the constant pursuit of quality improvement, I have noticed something about fermentor racking arm orientation during fermentation and would like to solicit outside opinions. I'll explain, and then ask the question.

Our SOP is to orient the racking arm slightly downward (in a 4-5 o'clock position) before filling the fermentor. From there, fermentation and cold conditioning proceeds as you'd normally expect. When it comes time to fine the finished beer, we will turn the racking arm upward so we are able to do a few brief bursts with CO2 through the racking arm in order to homogenize the fining agent in the beer. When rotating the racking arm upward from the 4-5 o' clock position, we will get a good bit of burping or bubbling due to a void that exists inside the racking arm since filling the fermentor (imagine holding a cup upside down and submerging it in a liquid, where a void exists inside the cup when the cup is submerged. You tilt the cup, and the void fills with the liquid, displacing the gas inside).

With this in mind, here is my question: Is it possible that we are oxidizing the finished beer when rotating the racking arm upward, as we are filling that void inside the racking arm with beer? Conversely, recognizing that the void in the racking arm would contain some amount of O2 at the start of fermentation, would the yeast consume the oxygen in the void, leaving only CO2 to subsequently escape when we rotate the racking arm upward at that fining step? Obviously, there is an interface between fermenting beer and the void in the racking arm, so perhaps the O2 in the arm is consumed during fermentation, and so when we rotate the racking arm as described above, we are only displacing CO2. We have our reasons for leaving the racking arm oriented the way we do prior to fermentation, but if this is causing us to subsequently oxidize the finished beer when we rotate the arm, we must consider modifying our SOP!

Thank you kindly for any insight.