Ceci est une ancienne révision du document !
This project is part of a long-term plan to become more self-sufficient. Brewing one's own beer is a critical part of any plan that pretends to have self-sufficiency as a goal.
We are starting with so-called “beer kits” which are 1.8kg tin cans filled with malt and hops concentrate. These kits are easily found in large Canadian grocery stores and I purchased 2 kits the last time I visited Vancouver. It is almost impossible to find these kits in Switzerland, so I will be soon forced to start to make barley malt from scratch.
In addition to the beer kit, we use the following tools:
The hydrometer merits a bit of explanation. It is used to measure the density of the wort (malt+water mixture) at the start of fermentation and at the end. By subtracting the difference in density, we know how much wort has been transformed into alcohol. To get an accurate measurement, the hydrometer must float freely in the wort, so the level of the wort in the fermentation vessel must be deep, or a small sample of wort can be put in a graduated cylinder. This hydrometer was sold for CDN$11 and packaged in a clear plastic cylinder that was reasonably usable. Another trick is to spin the hydrometer in the wort before measuring or air bubbles on the glass will result in a false reading.
90% of the work of brewing beer from a kit is cleaning the equipment and the bottles. The cleaning is in 2 steps. The first step is to clean away dirt and stains as much as possible with soap and warm water (and scrubbing, if necessary). The second step is to sterilize all working surfaces by soaking in a weak bleach (eau de Javel) solution, 4ml per liter of water, for at least 20 minutes.
While one is waiting for the sterilization to finish, re-reading the fine manual is a good use of time.
Here is the beer kit that we are using for this experiment. My father who has been doing this for the last 15 years recommended it and it is reasonably cheap at CDN$12 each, but impossible to find in Europe. There is a list of URLs for beer kits at the bottom of this page, but I think that we will soon be switching to home-made malt.
Note for next time: do NOT forget to bring a proper can-opener!!!
The malt in this beer kit already has hops added to it. It pours as slow as molasses and the can needs to be rinsed with hot water to get it all into the vessel. Note for next time: bring oven mits!!!
The yeast works best around room temperature, so the wort is made by mixing boiling hot water and cool tap water in the right proportions and measuring with one's finger before adding the contents of the packet of dried brewers' yeast. If I remember correctly, we had 3 litres of boiling water and 10 litres of tap water at about 10°C. Note for next time: bring a thermometer!!!
At this point we screwed up. I wanted to make a malt-only beer and did not add white sugar and water. The result was that the level of wort in the vessel was too low and the hydrometer was resting on the bottom. I did not think about using the plastic cylinder that the hydrometer was packed in until the day after (2012-08-08), so the starting density that I measured was probably too low since one full day of fermentation had already passed. The measured specific gravity was 1.022, but I suspect that the real starting specific gravity was more like 1.027 since the wort seemed pretty active already. Note for next time: get a proper graduated cylinder, at least 30 cm tall!!!
The fermentation vessel that we borrowed from Michael is really nice. It has a close-fitting top with a screw-down retaining ring and a red plastic top that has been retro-fitted with an airlock (CDN$3).
The beer was bottled 2012-09-04 and at that point had a specific gravity of 1.010. This is an excessive time to wait since fermentation was probably complete after only 2 weeks. According to the table that came with the hydrometer, that corresponds to (3.6-1.3)=2.3% alcohol. Pretty weak.
9 1.5 litre PET bottles were rinsed, sterilised with bleach solution, rinsed again, primed with 2 teaspoons of white sugar, and filled by siphoning from the fermentation vessel through a 1cm-diameter silicone tube, about 1.5 metres long. The last 2 bottles were particularly turbid with yeast that got remixed in the beer. Here again we screwed up by allowing the end of the tube to rest among the yeast at the bottom of the fermentation vessel. Note for next time: during the last week of fermentation, elevate one edge of the vessel so that yeast concentrates in a corner. Either that, or get a carboy and do at least one decanting.
The upper contents of 2 PET bottles were decanted into 6 “beugel” bottles with resealable ceramic caps (washed and sterlised in the usual manner). The bottles were primed with 3 teaspoonfuls of white sugar dissolved in hot water. The rest of the beer was “unofficially” tasted and found to be yeasty and a somewhat weak.
“Official” tasting date. Only the beugel bottles were consumed after chilling in the freezer for 1.5 hours. The result was a reasonably clear darker-than-blond beer and an optimal level of carbonisation. 3 PET bottles were set on their sides to cool in the fridge.
Decanted the contents of 3 1.5 litre PET bottles into beugel bottles using the usual 1/2 teaspoon of sugar (dissolved in a little hot water) per bottle as primer.
For some reason, the beer seems to have improved! And I don't think it just a question of getting used to it. Aging helps maybe…
The object of this experiment was to brew a more potent beer by adding common granulated white sugar. This time I used:
Sprinkling the yeast on top of the frothy wort was a mistake. Afterwards there were a number of yeast clumps that needed to be broken up manually. Next time I am going to dissolve the yeast in a bit of warm water beforehand.
The hydrometer read 1.058 which corresponds to an absolute maximum possible alcohol final content of about 7.5%. We shall see…
Bubbling stopped. The hydrometer read 1.012 which corresponds to about 1.5% alcohol, thus the content at this point is about 7.5% - 1.5% = 6.0%. The beer is distinctly sweet, so there is still some fermentation left to go.
I did not really plan to let another week pass before bottling, but perhaps it was a good thing. The hydrometer now reads 1.002, so I assume that fermentation really must be complete. Specific gravity of 1.002 corresponds to about 0.2% alcohol, thus the alcohol content of the batch (before priming) is about 7.5% - 0.2% = 7.3%. The entire batch (instead of each bottle individually) was primed with a mixture of about 400g sugar with gelatin (normally used for making jam) dissolved in 1 litre of boiling water. The primer was evenly poured over the top of the batch without further mixing in order to avoid stirring up the yeast at the bottom. Final bottled volume was about 18.5 litres, so there was a fair amount of spillage, perhaps 3 litres.
The 1-litre bottle from “Les Brasseurs” exploded some time during this last week. One of the PET bottles got knocked over and lost about 300ml, but there were no other losses. Bits of glass blew into the next room and the sugary beer glued small shards of glass to the floor of the machine room. Now I have to figure out some way of isolating these potential bombs.
Opened one of the 330ml bottles and measured its specific gravity at a little more than 1.002, probably due to unfermented primer. The beer is too sweet to be called “ready”.
No further explosions these last 2 weeks, but the room-temperature bottles remain difficult to open without squirting half of the contents all over the place. Bottles cooled in the fridge are almost reasonable, however. The beer is still a bit sweet, but it is definitely ready. The “greenish” taste has gone away as well as most of the excess sugar.
Started the alcotec (TM) 48 Turbo Super Yeast “hooch” test this evening. Followed the instructions more-or-less exactly, except that the starting temperature of the mix was 36°C rather than 40°C. But I wonder if I did not mistake the amount of water that I added which was supposed to be 21 litres. Hydrometer shows a specific gravity of 1.117 which corresponds to a potential of 15.5% rather than the 20% that I was aiming for. Even if one adds the 0.0032 correction due to the elevated temperature (from hydrometer tables), the potential is only 15.8.%. Maybe there is a lot of undissolved sugar at the bottom? Check next time.
Examined the hooch. There is a distinct odor of booze coming from the vat which is full of liquid that looks like diluted milk. No bubbles or foam, but there was a bit of fizz when I scooped out a 200ml sample. The taste was extremely sweet and fizzy, like a soft drink. There was also a disagreeable odor similar to white glue, so it is pretty horrible to drink neat. Specific gravity was 1.014, corresponding to 2.2% alcohol, therefore there is already 15.5% - 2.2% = 13.3% alcohol in the solution.
Decanted the mix into one and a half 19-litre water fountain bottles. The stuff still stinks and I did not bother to measure its specific gravity. A fair amount of yeast was left behind, but the liquid is still quite turbid.
Liquid seems to be less turbid after a week of settling and there is a layer of yeast at the bottom of the water bottles too.
Specific gravity is 0.984 at 20°C, one tick above the minimum measurable on my hydrometer. Most of the “glue smell” is gone and a large part of the sweetness. Mixed a cocktail of 100ml of hooch plus an equal amount of orange juice and was almost unable to detect any odor other than orange juice.
|The % alcohol (By Weight) if your brew is 14.8.|
|The % alcohol (By Volume) if your brew is 18.4.|
In November I made several attempts at drinking modest quantities (100-200ml) of the hooch mixed with orange juice and each following morning I suffered from hang-overs of a strength proportional to how much I had consumed. I conclude that the hooch is probably contaminated with acetaldehyde or something similar.
As a first step to purifying the hooch, I have ordered 1kg of Granucol FA activated carbon granules from Brouwland in Belgium. Hopefully this will help to neutralise the odor (which is already pretty reasonable) and absorb some contaminants. I found this list which indicates that activated carbon absorbs acetaldehyde as well as many other organic compounds including, unfortunately, ethyl alcohol. Hopefully the ethanol is less attracted to the carbon…
At this point the hooch has lost most of its milky-white color.
Tried concentrating by freezing the hooch in a plastic Coke bottle for about 1.5 hours at -16°C and then dumping the resulting slush (resembles a marguerita) into a funnel to filter out the liquid part. Did the same thing for a bottle of beer of the last batch. In both cases the remaining ice had lost most of the original flavor, indicating that the liquid was concentrated “good stuff”. The liquid in both cases did not really change taste, in my opinion, but others said that they tasted a difference. Finished the beer, but the hooch is currently undrinkable so I dumped the sample.
About 8 months after the original brewing of the hooch, I decided to redo the concentration experiment and measure the densities with a high-concentration hydrometer that can measure up to 100% alcohol. This time I used a rectangular tupperware and 400ml of hooch.
|15h05||21.5°C||infra-red and contact thermometer agree within 0.3°C|
|15h55||-6°C||using only infra-red thermometer, no ice yet|
|16h30||-15°C||maybe a few bits of ice floating|
|17h25||-12.2°C||more slush, but no real chunks of ice|
|18h00||-13.1°C||slush starting to stick too walls|
At this point I tried filtering the slush with a funnel, but it was too fine and did not want to separate into liquid and solid phases. Put the hooch back in the freezer to try again on Tuesday.
On 2012-12-06 I received the kit ordered 2012-12-01 from SIOS containing a 4.7kg sac of malted barley, 2 small sacs of pelletised hops, and 1 small envelope of dried yeast.
This is the first “real” beer recipe that we have tried. Frankly, I feel that using malt+hops out of a can is like making a Betty Crocker cake (add water, an egg, mix, pour in the pan, put the pan in the oven). The proposed recipe can be found here and a half-comprehensible Google translation into English is here.
No plan survives a battle and neither did the above recipe after we decided to improvise. The most important difference is that we used the "brew-in-a-bag" technique to avoid lautering (or sparging) steps. Lautering is basically filtering the wort through the barley mash after it has been cooked in order to trap as much barley waste as possible, keeping only the liquid portion. This requires a special lautering tun and while it is necessary for massive batches, cooking in a voile-cloth bag and lifting the bag out of the pot has a similar filtering effect.
Since Michael had received a grain grinder as part of his brewing kit, I had elected to start from whole grains rather than have SIOS grind them for a CHF4 fee.
After reading the manual and experimenting with the grinder tension screw, we found a setting that seemed to produce broken barley grains without turning them into powder. This is ideal because one wants the hot water to reach the heart of the grains, but one also wants to be able to filter out the solid bits after cooking. Lloyd managed to grind the 4.7 kg of barley in about 45 minutes. The job was mostly effortless, but perhaps a bit tedious after a while.
After a break for lunch, we lined the interior of the electric cauldron with the cloth bag and heated 25l of water to 78°C. We carefully added the crushed barley, stirring it in without adding air. We just barely managed to get everything in - the liquid level was less than 1cm from the edge of the cauldron. By the time that all of the barley had been stirred in, the temperate had dropped to 67°C and it took 15 minutes to recuperate. We gently stirred the barley mash at least once every 5 minutes, bringing up spoonfuls of mash from the bottom of the cloth bag. The odor reminds one very strongly of Ovomaltine. Because the wort was so close to the edge of the cauldron, we made a special effort to skim off any floating barley husks that caused foam to build up.
We removed the bag and while 2 of us held the bag open, another scooped a couple of litres of hot wort from the cauldron and carefully poured it through the mash. After squeezing out as much wort as possible from the mash, we set the wort to boil starting at 16h45. At this point I think we had about 20 litres of wort.
Getting the wort to boil was problematic. Even with the cauldron on maximum, we barely reached a little roiling boil after 30 minutes. It would have helped if we had dared to put the top on the cauldron, but we feared that it might boil over. In addition, we wanted water to evaporate. I believe that the ideal solution (for the future) is to insulate the sides of the cauldron, perhaps with a blanket like in some Youtube videos.
We compared the submersible thermocouple thermometer to the infrared thermometer and learned that the infrared gives erroneous low readings in the presence of water vapor.
We put the contents of the most acidic sac of hops in a “sock” and set it to boil in the wort, clamping the sock to one of the cauldron handles. In the future we should use clothes pins, not carpenter's clamps.
We put the contents of the second sac of hops in another “sock” and set it to boil in the wort too.
The copper wort cooling coil was hooked up to the water and left in the boiling wort for 10 minutes to be sterilised.
The cauldron was turned off and the cooling water was turned on at a fairly high flow. The temperature of the wort plunged from 98°C to 25°C in about 15 minutes. I was surprised at how effective the coil was because other blogs mention cooling times typically about 25-30 minutes.
Stopped cooling. Noticed strange delicate formations of protein floating in the wort.
After elevating one edge of the cauldron with a block of styrofoam, we siphoned the wort into the fermenting vat. To fill the siphoning hose, I had to suck on the bottom end and I got a mouthful of wort. Mildly sweet, not over-powering; I was expecting something stronger.
We stopped the siphoning with about 2 litres of very turbid wort and mash left at the bottom of the cauldron. I regretted leaving so much behind. The pre-made filtering brewing bag looks fine, but the bottom is made of a coarser mesh to help drain the mash which allowed too many broken grains to get through. In might be worthwhile to sew another bag of a finer-meshed cloth.
Measured the O.G. of the wort @25°C: 1.052
Estimate that the amount of wort is only 17 litres.
Sprinkled the packet of dried yeast onto the surface of the wort, screwed down the lid of the vat, and agitated the vat back and forth for 1.5 minutes. Filled the airlock with hooch and sealed the vat, storing it on the floor of the shower room which had a floor temperature of 18-19°C.
Specific gravity of the wort is 1.032 @20°C. I am a bit concerned because there seems to be no krausen (floating foam). Stirred up the wort for a minute, aerating it somewhat.
Specific gravity of the wort is still 1.032, but the wort is only 14°C! Unfortunately the door to the shower room was closed and air from outside chilled the room by 6°C with respect to the rest of the lab. Moved the fermentation vat to the kitchen area (20°C) and aerated it again to try to breath some life into the yeast.
Specific gravity of the wort is still 1.032 and research for “stuck fermentation” indicates that a chill can cause yeast to become permanently dormant. Re-pitching a new batch of yeast is the most commonly proposed solution. Checked the gunk on the bottom and it looks like a pretty thick layer of yeast, so it must have lived for a little while at least.
Ordered another packet of top-fermenting dried yeast from SIOS.
Received the packet of yeast in this morning's mail.
The wort has not changed specific gravity; it is still 1.032.
Boiled about a cup of water and dissolved a tablespoon of sugar in it. Waited until the temperature of the sugar solution was about 27°C before sprinkling the packet of yeast into it. It was necessary to squash the grains of yeast with a spoon since they clumped-up and refused to dissolve otherwise. After about 25 minutes, the yeast “cream” had a bit of a head of foam on it. Pitched it into the wort without stirring too much in order to avoid disturbing the bottom layer of old yeast in the fermenting vat.
I think this beer is lost. There seem to be delicate mats of scum floating near the surface resembling a kombucha culture. Tasted the wort and it has a bit of a sour vinegar taste. Specific gravity is still about 1.032 or maybe 1.031. I will wait until after the new year before deciding whether or not to dump this batch.
In February I attempted to use some of the beer as the liquid base for a soup, but it was already too sour. The left-over soup was somewhat fixed by adding cream, but I decided that this batch of beer was a loss and dumped it.
I kept a sample of the beer and the yeast sludge from the bottom with the idea of looking at it under a microscope to see if I could identify what was living there. My hypothesis is that it is some mixture of dead yeast and living lactobacillus. Michael brought a 600x USB microscope to the lab, but I was unable to see any microbes.
Paul took a sample home with him and tested it with a pH measurement powder. It measured 4, which is about the same acidity as tomato juice according to this pH scale.
One month after having ordered the granules of activated carbon from Brouwland, they finally arrived. IMHO, TnT sucks as a courier service.
Unfortunately, after reading a 28-page mini-book on activated carbon and the technical specifications of Granucol FA, I think that I ordered the wrong format of carbon. I probably should have ordered 0.4mm granular stuff for filtering nasty tastes whereas the Granucol FA seems to be pressed-powder pellets, specially formulated dissolve into wine must to remove excess color. There is no way that I will be able to make a filtering column with this stuff.
Nevertheless, I did the following experiment.
I took the contents of 2 half-litre bottles of hooch, emptied into a stainless steel bowl, and added a few drops of green food color. After mixing, I used a funnel to pour half of the green hooch into one bottle and half into the other bottle containing about 1 gram (+-0.5g) of Granucol FA pellets. This dose of 2g/litre was double the maximum recommended for red wine (1g/litre).
The pellets dissolved on contact with the hooch and turned it into a black murky liquid. After allowing it to work for a couple of days (shaking the bottle 4 times per day), the green tint and odd tastes and odors should disappear with a black sludge settling at the bottom of the bottle. This sludge can later be removed by decanting. I hope.
I should note here that drinking moderate amounts (<300ml) of hooch no longer causes me headaches or nausea, so perhaps purification is not absolutely necessary.
(WHERE IS THE PHOTO?) After 2 weeks the bottle treated with carbon had cleared and there was no green tint left. However, the liquid still had a bit of milky tint to it. Perhaps the pore size of this carbon is really good for removing color, but it does not seem to work so well on larger floating impurities.
2013-04-01 to 2013-06-30
In April I attempted the same experiment on a grander scale. I divided the 20l of hooch into two containers, 10l each, and added 10g of carbon to one of the containers. After 4 weeks the carbonised container was much clearer than the non-carbonised container. People who tasted the cleared, carbon-treated hooch found it to have a much cleaner taste.
I found that both the clean and the murky hooch have approximately the same taste effect when mixed with orange juice, but the cleaner one might cause less-sever headaches.
2013-09-03 to 2013-09-15
The first experiment with the Altbier demonstrated that having a stable temperature is important for brewing beer. I decided to measure temperature during a couple of weeks in the Usine and Cellier (under the stairs) areas of the lab. I bought a Raspberry Pi, equipped it with a WiFi USB dongle, and attached 2 DS18B20S 1-wire temperature sensors, using http://andyseasysite.com/?p=11 as a starting point. NOTE: The Fritzing diagram in the tutorial is incorrect, showing the temperature sensor wired in backwards.
The first series of measurements was done in the Cellier from 2013-09-03 to 2013-09-10. There were 2 temperature probes, one probe (green line) on a breadboard fastened to the Raspberry Pi and the other probe (red line) about 50cm away. The red line gives the most correct temperature of the room. The green line shows a couple of higher-temperature plateaus corresponding to times when there were a lot of WiFi users in the lab.
The second series of measurements was done in the Usine from 2013-09-10 to 2013-09-14.
The temperature in the Usine ranged from 19°C to 23.5°C which is far more variable than the Cellier which ranged from 25.3°C to 26.3°C. This is due to air entering the Usine via a duct from underneath a grating in the sidewalk outside of the building. I concluded that even though the temperature in the Usine is closer to the ideal brewing temperature of Altbier (18°C) it would be safer to wait a few weeks and do all of the brewing in the Cellier. The dust in the Usine is another reason to move the brewing activities elsewhere.
When we brewed the Altbier we were disappointed with how slow the cauldron was at heating the mash and wort. Here I measure the temperature curve of 20 litres of initially cold tap water heated at maximum power. The cauldron is wrapped in a aluminium-mylar-and-foam blanket and the cauldron is covered.
Even with the insulating blanket, it is going to take about 50 minutes to heat the brew to 80°C. We might be able to speed things up by using a kettle to boiling water.
SIOS had a sale of 6 different Cooper's beer kits for CHF100. They are all nearing their “best-by” date, so before I do another Altbier, I decided to brew the Cooper's dark ale kit. The instructions in the kit indicate that it is much more tolerant of higher temperatures which seems logical for beer coming from South Australia.
Proceeded according to the recipe with one exception. Instead of directly sprinkling the yeast onto the wort, I first prepared a cube of sugar dissolved in a half-cup of warm water and mixed the yeast into the water when it was about 28°C. When it came time to add the yeast to the wort, there was a small amount of foam floating on the yeast water, indicating that the yeast was indeed alive. The wort was 28.2°C when I added the yeast, which is a little outside of the recommended range of 21°C-27°C.
Here is what I noted on the brewing record that came with the instructions:
Theoretically this should result in a normal 5%abv ale.
Michael took a few photos of me and Vincent:
This batch was set to brew in the Cellier, sitting on top of the raspi temperature probe.
Measured the specific gravity to be 1.012, so not quite ready for bottling, in my opinion. Although I was pretty careful when I deplaced the fermenting vat, there was still a bit of sloshing that probably disturbed the trub on the bottom.
It took longer than I remembered to get set up for bottling the beer, but I did a few things differently this time. To avoid getting a lot of trub mixed with the beer during the bottling process, I siphoned into one of the 19l water bottles, losing 2 litres of beer in the process. If the water bottle had been big enough, I think I would have sacrificed only 0.5l.
The priming was accomplished by mixing approximately 20lx8g/l of jam sugar (white sugar with gelatin) in 0.5l of boiling water, stirring until perfectly dissolved, adding to the water bottle, and then siphoning from the fermenting vat into the water bottle.
The beer is very dark but otherwise clear. There were brown crumbs of krausen floating on the surface of the fermenting vat. I hope not too much got into the bottles in the end.
Bottled the beer with the help of Mara. Re-discovered the advantage of using the bottling cane versus blocking the siphon hose with one's thumb: much less spillage and less air mixed into the beer. I started getting set up (mixing priming solution) at around 17h30 and we finished bottling (with clean-up) at around 20h15.
There were about 30x350ml bottles and 20x500ml bottles. The smaller bottles may be contaminated with a bit of eau-de-javel taste because I think I forgot to rinse them.
http://www.brewferm.be/en/experts.htm Instruction pour kits avancé brewferm
Swiss online shop:
http://www.beersmith.com/recipes.htm repice from brewsmith website
Special thanks to: