So going back to a story previously told in regards to measuring efficiency, I now have some results to share. Disappointed with how poorly I missed my target volume efficiency, I went about some new modifications. Simple, yet elegant. I put a few things into the sytem just tonight alone.
First, I installed a sight glass into the boil kettle. This sight glass protudes out of the keg and runs parallel on the outside of the keg in a vertical position. Picture this as the handle to a milk carton. The handle on the milk carton shows the level of milk equal to that of what is in the container. The sight glass serves the same purpose as a keg is non-transparent. It measures up in increments of 1 gallon, starting at 3 gallons and ending at 15 gallons. I can use a ruler to get half gallon, two-third gallon increments, etc if need be.
The installation consisted of drilling a 9/16" hole near the bottom of the keg, inserting a threaded elbow, washer, and silicone gasket. It took all but 10 minutes to install and already serves a timesaver. Now when I have to put 13.3 gallons of mashed wort into the boiler, I just look over and turn off the pump as needed.
My second test was to conduct an evaporation rate experiment. I put in about 11 gallons of water and heated to 150F. I then shut off the flame, and pumped out 1 gallon so my remaining volume equalled 10 gallons. I stopped at 150F because normally when I mash i am in the 150-155F range. I adjusted and recorded 3 various gas valves to maintain consitency on future brewdays.
1.) Opened propane tank valve to 'full open'
2.) Opened boil kettle burner valve to 'full open'
3.) Opened adjustable propane regulator 1.5x and even took a picture to eyeball it up next time.
After that, I let her rip and get to a full rolling boil for about 1 minute. This is when I will add hops and start my 60 minute, 75 minute, or 90 minute boil timer. For this experiment I set my 60 minute timer. I had exactly 10 gallons and had been maintaining 212F for 1 minute. It just so happened to be 8:54 PM. Needless to say, at 9:54 PM I put the flame out. I had just under 8.5 gallons remaining. According to Beersmith (software I use), my evaporation rate is at 12%.
12% is a little on the high side, but it may be something I work on down the road. I may have to do another experiment where I crank the heat from mash temp levels to boiling and then adjust the flame to maintain a very soft, gently rolling boil. It may make a difference, it may not. We may never know.
At least I know I have a 12% evaporation rate. I adjusted my equipment profile on beersmith to calculate for that. Last bacth we brewed started with 13.3 gallons of beer and ended up with about 8.5 -9 gallons in the fermenter. My target was 11. The equipment profile was set up for 9% evaporation, hence the loss. Now, the same recipe says start with 14.4 gallons in the boil to end up with 11 in the fermenter. I can and should be able to achieve that now.
The third modification was those dreaded pumps on the wort chiller. After I boil, my goal is to get the boiled beer from 212F to about 65F as fast as possible to prevent infection/bacteria, etc. My first two batches ever went fine, but the last 4 batches gave me nothing but problems. Some of the connections used are stainless steel couplers (threaded with teflon), some were non-teflonned, and some couplers were even plastic. I had leaks in multiple spots. This is where the problem was. Where there is a leak, air gets in. When air gets in, pumps can't prime, etc.
I swapped out every plastic couple for new ss ones and taped every connection. The flow rate increases dramatically and the pumps primed instantly. Batch 1 and 2 cooled from 212F to 65 in about 15 minutes. Batches 3-7 took about 45 minutes. Tonights test run took 11 minutes.
212F - 100F took 5 minutes
100F- 90F took 90 seconds
90F- 80F took 90 seconds
80-68F took 150 seconds
I couldn't believe it. Rarely do I attempt 3 things and achieve them all. I was perplexed and surprised with joy after successfully making all 3 modifications tonight. They went as planned. Now I am planning on making a nice, creamy porter to get me through these cold days of winter.
Take care......until next time
Friday, November 12, 2010
Tuesday, November 2, 2010
Efficiency: Why and What You Need to Know
Ok, so you already saw the prequel to this post The Yeast Starter. The good news is that the 2000ml yeast starter was sufficient in handling the fermentation associated with this Belgian Dubbel/Trippel Chimay Clone. The funny thing is that on brewday we overshot our OG and ended with a higher gravity than anticipated.
This is due to several factors:
1.) Set my efficiency too low at 75%.
2.) Increased the grain bill to make up for an anticipated lower efficiency at 68%.
3.) Increased Dark Belgian Candi Sugar to make up for an anticipated lower efficiency at 68%.
4.) Boiled hot an heavy and evaporated too much water.
So basically, while this beer is going to be great, it taught me that I still have to determine my efficiency on my system. I'd be happy by all means with an efficiency in the 80 percentile, but would be astonished and dumbfounded if I could get an efficiency in the 90 percentile.
Efficiency is determined by calculating the total grains available for brewday and calculating how many possible fermentables were converted. Evaporation rate also plays a factor in the calculation. Essentially, if I set my evaporation rate at 9% per hour and boil off exactly 9% per hour; and if I have 30 pounds of grains and extract all the possible sugars from these grains, then I have 100% efficiency. It raises a good question that I'd like to know the answer for. What are commercial brewery efficiencies like? I'd be willing to bet they get 85-94% efficiency (possibly more), while homebrewers get anywhere from 60-90% efficiency, depending on the setup and equipment used.
I thought my efficiency would be determined over the last 5 batches, but the factors keep changing batch after batch. Number one being, I brew something different and a different quantity every time. I will do a dry run with evaporation rate. I will transfer water to the boil kettle at 150F as that is a safe mash temp and begin to boil. The second the first bubbly boil rises I will record how many turns my propane regulator is open and determine my true boil off at 60 minutes and 90 minutes being that these are the two most common boil times. This will assist me in my entire 'brewhouse efficiency.' Then I will do a cheap 1 gallon batch of just 2-row pale malt to see what my yield is, by calculating the mash/sparge process to my preboil gravity. This will determine my mash efficiency.
By default, Beersmith (the software I use to handle all my brewing calculations) is set at a 75% efficiency. Therefore, the grain bill, water quantities, etc is assuming a 75% efficiency. If I undershoot that 75% efficiency, then I have a beer with lower alcohol content than intended. Yep, that would be very disappointing. However, If I overshot the default 75% efficiency, then I would have a stronger beer. While that doesn't seem bad at all, it has its consequences. It actually tells me that I depending more on chance than pure science. Proper note taking allows one to make the same beer over and over again, just the way that one Budweiser batch after the other taste exactly the same. If you have various factors on different brewdays, its harder to replicate that. The more you control, the better off you are. The more you leave up to chance, the more risk you ensue.
So, let's take a look at what happened to me on this particular brewday.
We will look at Target Volume, Efficiency into Boiler, and Actual Volume Efficiency.
Brewhouse Efficiency Based on Target Volume
Actual OG: 1.083
Estimated OG: 1.075
Brewhouse Efficiency: 75.00%
Actual Efficiency: 84.56%
Efficiency Into Boiler
Volume into Boiler: 13.27 gallons
Planned Boil Volume: 13.27%
OG into Boiler: 1.067
Estimated OG into Boiler: 1.067
Efficiency into Boiler: 78.09%
Efficiency Into Fermenter
Actual Batch Volume: 9.50 gallons
Planned Volume: 11.50 gallons
Efficiency calculated from Volume: 68.16%
So, after reviewing the above, you will see I overshot OG by overcompensating my grain bill. I hit my OG into the boiler and the 13.27 as planned so I ended up with 78.09% efficiency. That's great. Where I failed is the efficiency into the fermenter because I planned for 11.50 gallons but only ended up with 9.50 so I had a 68.16% efficiency. That means I definately boiled off too much. I had the flame set too high. Once I determine my evaporation rate, it looks like my brewhouse efficiency would be 84.56%. That'll be something to be proud of. I'll send updates once I work on that.
Once I do that, I can set beersmith to calculate everything from grain bill to hop quantities to water needed to everything else at 85% and won't have to adjust anything. Like I said earlier, I assumed a 68% efficiency so I added more grains and more belgian candi sugar, and as a result ended up with an 84.56% efficiency in regards to Alcohol Content but underscored in regards to my final volume at 68.16%. I was supposed to have 11.50 gallons of beer to ferment, but ended up with 9.50 gallons.
Going back to the fact that I need to take good notes correlates with the fact that I am relying on chance. If this beer turns out phenomenal, I'll never be able to duplicate it without some sort of noticeable difference in character and taste, unless by chance I end up with all the same gravities and efficiencies mentioned above.
So now you know what Efficiency is when discussed in the homebrew community. By now, you should have some better understanding of how it affects your brewing process. Essentially, it affects the cost of the beer if you have to buy more grains than what would be needed on a more efficient system. You can utilize less of every ingredient with better efficiency and end up with more beer at the end of the day if you do it right. Needless to say, I am disappointed because I could have/should have had this all determined months ago. I have some work ahead of me and will report back.
Two new discussions in the works: 1.) The Chimay Clone Outcome and 2.) Using pumps and how to prevent wasted time from day 1.
VIDEO LINK: Just a quick shot at the brewing process. At this point, the mash tun (middle keg) is steeping 30 pounds of grains in 8 gallons of water at 149F. The HLT (right keg) is filled with 9 gallons of water and is in the process of being heated to 167F to use for sparging.
http://www.youtube.com/watch?v=MmwlmxfPmZs
This is due to several factors:
1.) Set my efficiency too low at 75%.
2.) Increased the grain bill to make up for an anticipated lower efficiency at 68%.
3.) Increased Dark Belgian Candi Sugar to make up for an anticipated lower efficiency at 68%.
4.) Boiled hot an heavy and evaporated too much water.
So basically, while this beer is going to be great, it taught me that I still have to determine my efficiency on my system. I'd be happy by all means with an efficiency in the 80 percentile, but would be astonished and dumbfounded if I could get an efficiency in the 90 percentile.
Efficiency is determined by calculating the total grains available for brewday and calculating how many possible fermentables were converted. Evaporation rate also plays a factor in the calculation. Essentially, if I set my evaporation rate at 9% per hour and boil off exactly 9% per hour; and if I have 30 pounds of grains and extract all the possible sugars from these grains, then I have 100% efficiency. It raises a good question that I'd like to know the answer for. What are commercial brewery efficiencies like? I'd be willing to bet they get 85-94% efficiency (possibly more), while homebrewers get anywhere from 60-90% efficiency, depending on the setup and equipment used.
I thought my efficiency would be determined over the last 5 batches, but the factors keep changing batch after batch. Number one being, I brew something different and a different quantity every time. I will do a dry run with evaporation rate. I will transfer water to the boil kettle at 150F as that is a safe mash temp and begin to boil. The second the first bubbly boil rises I will record how many turns my propane regulator is open and determine my true boil off at 60 minutes and 90 minutes being that these are the two most common boil times. This will assist me in my entire 'brewhouse efficiency.' Then I will do a cheap 1 gallon batch of just 2-row pale malt to see what my yield is, by calculating the mash/sparge process to my preboil gravity. This will determine my mash efficiency.
By default, Beersmith (the software I use to handle all my brewing calculations) is set at a 75% efficiency. Therefore, the grain bill, water quantities, etc is assuming a 75% efficiency. If I undershoot that 75% efficiency, then I have a beer with lower alcohol content than intended. Yep, that would be very disappointing. However, If I overshot the default 75% efficiency, then I would have a stronger beer. While that doesn't seem bad at all, it has its consequences. It actually tells me that I depending more on chance than pure science. Proper note taking allows one to make the same beer over and over again, just the way that one Budweiser batch after the other taste exactly the same. If you have various factors on different brewdays, its harder to replicate that. The more you control, the better off you are. The more you leave up to chance, the more risk you ensue.
So, let's take a look at what happened to me on this particular brewday.
We will look at Target Volume, Efficiency into Boiler, and Actual Volume Efficiency.
Brewhouse Efficiency Based on Target Volume
Actual OG: 1.083
Estimated OG: 1.075
Brewhouse Efficiency: 75.00%
Actual Efficiency: 84.56%
Efficiency Into Boiler
Volume into Boiler: 13.27 gallons
Planned Boil Volume: 13.27%
OG into Boiler: 1.067
Estimated OG into Boiler: 1.067
Efficiency into Boiler: 78.09%
Efficiency Into Fermenter
Actual Batch Volume: 9.50 gallons
Planned Volume: 11.50 gallons
Efficiency calculated from Volume: 68.16%
So, after reviewing the above, you will see I overshot OG by overcompensating my grain bill. I hit my OG into the boiler and the 13.27 as planned so I ended up with 78.09% efficiency. That's great. Where I failed is the efficiency into the fermenter because I planned for 11.50 gallons but only ended up with 9.50 so I had a 68.16% efficiency. That means I definately boiled off too much. I had the flame set too high. Once I determine my evaporation rate, it looks like my brewhouse efficiency would be 84.56%. That'll be something to be proud of. I'll send updates once I work on that.
Once I do that, I can set beersmith to calculate everything from grain bill to hop quantities to water needed to everything else at 85% and won't have to adjust anything. Like I said earlier, I assumed a 68% efficiency so I added more grains and more belgian candi sugar, and as a result ended up with an 84.56% efficiency in regards to Alcohol Content but underscored in regards to my final volume at 68.16%. I was supposed to have 11.50 gallons of beer to ferment, but ended up with 9.50 gallons.
Going back to the fact that I need to take good notes correlates with the fact that I am relying on chance. If this beer turns out phenomenal, I'll never be able to duplicate it without some sort of noticeable difference in character and taste, unless by chance I end up with all the same gravities and efficiencies mentioned above.
So now you know what Efficiency is when discussed in the homebrew community. By now, you should have some better understanding of how it affects your brewing process. Essentially, it affects the cost of the beer if you have to buy more grains than what would be needed on a more efficient system. You can utilize less of every ingredient with better efficiency and end up with more beer at the end of the day if you do it right. Needless to say, I am disappointed because I could have/should have had this all determined months ago. I have some work ahead of me and will report back.
Two new discussions in the works: 1.) The Chimay Clone Outcome and 2.) Using pumps and how to prevent wasted time from day 1.
VIDEO LINK: Just a quick shot at the brewing process. At this point, the mash tun (middle keg) is steeping 30 pounds of grains in 8 gallons of water at 149F. The HLT (right keg) is filled with 9 gallons of water and is in the process of being heated to 167F to use for sparging.
http://www.youtube.com/watch?v=MmwlmxfPmZs
Teaser: The Chimay Clone finished fermenting out at 1.008 from 1.083. Subtract 1.008 from 1.083 and multiply by 131 to get ABV. In this case, we're looking at a 9.82% beer. One and buzzed, two and drunk, three and you'll regret it.
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