I am trained as a scientist, so if this writeup seems a bit overly formal, please excuse it as either a character flaw or an admirable trait. Can’t help it. 
This is somewhat long, but if you don’t care about the specifics of how the beer was brewed, skip to the RESULTS sections below.
VARIABLE, RECIPE and BREWING METHODS
The variable tested was the use of BrewtanB, a tannic acid addition to both the strike water and the boil (1 gram in strike, 1.34 grams in boil). Hereafter abbreviated as BtB, BrewtanB is thought to increase shelf life of beers, especially hoppy beers that can be prone to losing the brightness of hop aroma and flavor. There is thought that this product can reduce the effects of oxidation, which is also known to be the enemy of hoppy flavor and aroma.
We used Kory’s all-grain KPA recipe (Kory’s Pale Ale) which has 6# of 2-row, 4# of Maris Otter, 1# of Munich, and 1# of Crystal 60L. Hops were 1oz of Warrior at 60 minutes, 1 oz of Cascade at 10 minutes, 1 oz of Cascade at flameout. It was dry hopped with 1.5 oz of Cascade and 1 oz of Simcoe, using stainless hop tube screens suspended in each fermenter. A whirlfloc tablet was used at 15 minutes. The method used was Brew-in-a-Bag. Each batch was done this way.
Yeast was WLP001, two packs made in a single starter. That starter wort was oxygenated (oxy tank and wand) for 30 seconds, and a 1/8 tsp of yeast nutrient was added to the starter during boiling the DME. It was on a stir plate for 18 hours prior to pitching. The starter was measured out into each batch using a graduated beaker so each received the same amount.
As is my custom, we pitched the starter directly into the wort without first cold-crashing and decanting off the liquid from the starter. There was activity on both within 7 hours, and the BtB batch was faster starting up by about an hour.
It was fermented at 64 degrees; after the krausen had fallen on the fifth day the temp was bumped up to 68 degrees, and then to 71 degrees the next morning, to allow the yeast to clean up. After 48 hours at 71 degrees the beer was dropped to 64 for a week, during which time we dry hopped. Finally both beers were crashed to 36 degrees (no finings), and then racked to kegs, and then force carbonated.
The two batches were brewed sequentially, requiring careful attention to times and temperatures. One was brewed in the morning, one in the afternoon. In each case the grain was crushed just prior to doughing-in. Mash temperature was 151.7 for the control, 152 for the BtB. PH of the two batches, taken at 15 minutes and using a freshly-calibrated meter, were 5.32 for the control, 5.28 for BtB. (A chemist friend indicated that yes, the difference in pH could well be from the effects of the tannic acid in BtB, though he hadn’t calculated it). Either way, except for the fact that one batch had BtB and one did not, these were as close to identical as we could make them.
How to equalize pitching of the yeast was an issue. What I wanted was to pitch the yeast starter into wort at 71 degrees, then drop it to 64 in the ferm chamber. Since the brewing of the two batches was offset by 4 hours, the first one (control) was kept in the ferm chamber at 71 degrees while the BtB batch was being brewed. The BtB batch was chilled to the same temp of 71, and then it was into these two fermenters that the yeast was pitched. The wort in both batches was oxygenated using an O2 tank and wand prior to pitching.
That way both started at the same time, at the same temp (71), with the same yeast, and the same residual oxygen. The temp controller in the ferm chamber was then set to 64 degrees (running off the BtB fermenter) and off they went. We used a second controller temp probe on the control fermenter so we could monitor both fermenter temps. Both were within .5 of each other throughout the fermentation.
RESULTS, Part 1–November 1st–Tasting 32 days after brewing.
Results from our testing of Brewtan-B at the DBQ SOB–Society of Brewers--meetings.
Tasters were asked to come to the meeting with a clean palate, i.e., no beer drinking prior.
They were also served the beers in a rotating order. There are six possible combinations of one and two beers, signified by B for BrewtanB and C for Control: CBB, CBC, BBC, BCC, CCB, BCB. To try to address possible ordering effects, each taster was given the beers in a specific order and asked to taste them, initially, in that order, then to go back and forth as they wished. There were two each of the various orders and one extra of the first one, i.e., three tasters had the CBB order, and there were two tasters in each of the other possible orderings.
Of the 13 taste-testers, 7 were able to identify the “odd beer out.” They were then asked to produce some comments on the beers.
From a “significance” point of view, 7 out of 13 is not enough to achieve significance at the .05 level (P=.1035). In other words, the results were not significantly different from what we might expect if tasters were just randomly guessing.
(As a side note, I had a local guy, homebrewer, also do the test, but he did it from the kegs directly and not on the same day; he picked the correct odd-one-out, and preferred the BtB sample. Even if I add him to the results, which would be 8 out of 14, we still don’t quite reach the .05 level of significance (p=.0576).)
Comments of those who preferred the BtB beer:
1. Less Hoppy, little sweeter
2. Seems to be a touch more hoppy, very similar to the other, both are great beers
3. Hop combination, hoppiness
4. Hops fresher, carbonation a tad more
Comments of thsoe who preferred the Control beer:
5. Maltier and smoother
6. Not sure why, just seems to have a little cleaner finish, perhaps due to carbonation level
7. Watery (Lite), smooth. Comments on the nonpreferred BtB sample were “Light, creamy, a little hoppier, bitter.
The carbonation comments are confusing to me. Both beers were carbonated identically off a single line that was split to each keg. The beers were bottled using a “poor man’s beer gun” arrangement (see pic) where you use a picnic tap to feed a rigid tube passed through a drilled stopper that fits the bottle. This kept foaming down as the bottles were filled.
What conclusions do I draw from this? I really have difficulty drawing any that are definitive. While 7 of 13 picked the correct odd-one-out beer, that’s not “signficant.” Nor would 8 out of 14 be significant.
Further, the comments are somewhat contradictory. Look at 1 and 2 above as an example.
I wish I’d had access to a larger panel, say 20 or 30, but you can’t conjure that up out of thin air. There were others at the meeting, of course, but some had already had a beer or two. Perhaps I might have had them taste the beers anyway and kept their comments separate.
We’ll see how these are in a few months.
<continued on next message>
This is somewhat long, but if you don’t care about the specifics of how the beer was brewed, skip to the RESULTS sections below.
VARIABLE, RECIPE and BREWING METHODS
The variable tested was the use of BrewtanB, a tannic acid addition to both the strike water and the boil (1 gram in strike, 1.34 grams in boil). Hereafter abbreviated as BtB, BrewtanB is thought to increase shelf life of beers, especially hoppy beers that can be prone to losing the brightness of hop aroma and flavor. There is thought that this product can reduce the effects of oxidation, which is also known to be the enemy of hoppy flavor and aroma.
We used Kory’s all-grain KPA recipe (Kory’s Pale Ale) which has 6# of 2-row, 4# of Maris Otter, 1# of Munich, and 1# of Crystal 60L. Hops were 1oz of Warrior at 60 minutes, 1 oz of Cascade at 10 minutes, 1 oz of Cascade at flameout. It was dry hopped with 1.5 oz of Cascade and 1 oz of Simcoe, using stainless hop tube screens suspended in each fermenter. A whirlfloc tablet was used at 15 minutes. The method used was Brew-in-a-Bag. Each batch was done this way.
Yeast was WLP001, two packs made in a single starter. That starter wort was oxygenated (oxy tank and wand) for 30 seconds, and a 1/8 tsp of yeast nutrient was added to the starter during boiling the DME. It was on a stir plate for 18 hours prior to pitching. The starter was measured out into each batch using a graduated beaker so each received the same amount.
As is my custom, we pitched the starter directly into the wort without first cold-crashing and decanting off the liquid from the starter. There was activity on both within 7 hours, and the BtB batch was faster starting up by about an hour.
It was fermented at 64 degrees; after the krausen had fallen on the fifth day the temp was bumped up to 68 degrees, and then to 71 degrees the next morning, to allow the yeast to clean up. After 48 hours at 71 degrees the beer was dropped to 64 for a week, during which time we dry hopped. Finally both beers were crashed to 36 degrees (no finings), and then racked to kegs, and then force carbonated.
The two batches were brewed sequentially, requiring careful attention to times and temperatures. One was brewed in the morning, one in the afternoon. In each case the grain was crushed just prior to doughing-in. Mash temperature was 151.7 for the control, 152 for the BtB. PH of the two batches, taken at 15 minutes and using a freshly-calibrated meter, were 5.32 for the control, 5.28 for BtB. (A chemist friend indicated that yes, the difference in pH could well be from the effects of the tannic acid in BtB, though he hadn’t calculated it). Either way, except for the fact that one batch had BtB and one did not, these were as close to identical as we could make them.
How to equalize pitching of the yeast was an issue. What I wanted was to pitch the yeast starter into wort at 71 degrees, then drop it to 64 in the ferm chamber. Since the brewing of the two batches was offset by 4 hours, the first one (control) was kept in the ferm chamber at 71 degrees while the BtB batch was being brewed. The BtB batch was chilled to the same temp of 71, and then it was into these two fermenters that the yeast was pitched. The wort in both batches was oxygenated using an O2 tank and wand prior to pitching.
That way both started at the same time, at the same temp (71), with the same yeast, and the same residual oxygen. The temp controller in the ferm chamber was then set to 64 degrees (running off the BtB fermenter) and off they went. We used a second controller temp probe on the control fermenter so we could monitor both fermenter temps. Both were within .5 of each other throughout the fermentation.
RESULTS, Part 1–November 1st–Tasting 32 days after brewing.
Results from our testing of Brewtan-B at the DBQ SOB–Society of Brewers--meetings.
Tasters were asked to come to the meeting with a clean palate, i.e., no beer drinking prior.
They were also served the beers in a rotating order. There are six possible combinations of one and two beers, signified by B for BrewtanB and C for Control: CBB, CBC, BBC, BCC, CCB, BCB. To try to address possible ordering effects, each taster was given the beers in a specific order and asked to taste them, initially, in that order, then to go back and forth as they wished. There were two each of the various orders and one extra of the first one, i.e., three tasters had the CBB order, and there were two tasters in each of the other possible orderings.
Of the 13 taste-testers, 7 were able to identify the “odd beer out.” They were then asked to produce some comments on the beers.
From a “significance” point of view, 7 out of 13 is not enough to achieve significance at the .05 level (P=.1035). In other words, the results were not significantly different from what we might expect if tasters were just randomly guessing.
(As a side note, I had a local guy, homebrewer, also do the test, but he did it from the kegs directly and not on the same day; he picked the correct odd-one-out, and preferred the BtB sample. Even if I add him to the results, which would be 8 out of 14, we still don’t quite reach the .05 level of significance (p=.0576).)
Comments of those who preferred the BtB beer:
1. Less Hoppy, little sweeter
2. Seems to be a touch more hoppy, very similar to the other, both are great beers
3. Hop combination, hoppiness
4. Hops fresher, carbonation a tad more
Comments of thsoe who preferred the Control beer:
5. Maltier and smoother
6. Not sure why, just seems to have a little cleaner finish, perhaps due to carbonation level
7. Watery (Lite), smooth. Comments on the nonpreferred BtB sample were “Light, creamy, a little hoppier, bitter.
The carbonation comments are confusing to me. Both beers were carbonated identically off a single line that was split to each keg. The beers were bottled using a “poor man’s beer gun” arrangement (see pic) where you use a picnic tap to feed a rigid tube passed through a drilled stopper that fits the bottle. This kept foaming down as the bottles were filled.
What conclusions do I draw from this? I really have difficulty drawing any that are definitive. While 7 of 13 picked the correct odd-one-out beer, that’s not “signficant.” Nor would 8 out of 14 be significant.
Further, the comments are somewhat contradictory. Look at 1 and 2 above as an example.
I wish I’d had access to a larger panel, say 20 or 30, but you can’t conjure that up out of thin air.
There were others at the meeting, of course, but some had already had a beer or two. Perhaps I might have had them taste the beers anyway and kept their comments separate.We’ll see how these are in a few months.
<continued on next message>
