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This page describes some of the more interesting things about my brewing activity. I started with some brewing kits from Grumpy's Brewhaus, one of Australia's most public brewing supply houses, which happens to be just round the corner from where I live. Initially I brewed some of their (better than average quality) kits, but then I started doing my own thing.
The following entries relate to my online diary, but may have more details than in the diary.
Started a first experimental brew, number 10:
| quantity | ingredient |
| 3 kg | Coopers pale malt extract |
| 38 g | Fuggles hops (pellets) |
| 25 g | East Kent Goldings hops (pellets) |
| Coopers Pale Ale yeast starter | |
| 20 l | Total volume |
This was supposed to be a pretty standard base brew of pale ale, brewed at 18°. Made a bit of a mess of the cooling: didn't really think about it, so it ended up cooling in the fridge overnight. The Fuggles were boiled with the wort for 60 minutes, and the Goldings went into the fermenter at pitching time.
Down to Grumpys to pick up a can of malt extract and some hops, and also got some “wheat malt” extract. It seems that this is a misnomer: it's 45% wheat malt, 55% barley malt, which is written nowhere on the can. Good to know.
At Guilfoyles, discovered the cause of my confusion: a honey gate is just a kind of tap, so you can't use it on the original drum. Instead you need a second container to which you attach the gate. Fortunately, he had a second-hand bucket there and was able to fit it with the honey gate right away. After cleaning and filling, it looks like this:
| quantity | ingredient |
| 2.9 kg | Coopers pale malt extract |
| 700 g | Cane sugar |
| 38 g | Fuggles hops (pellets) |
| 30 g | East Kent Goldings hops (pellets) |
| Coopers Pale Ale yeast starter | |
| 26.5 l | Total volume |
The difference here was the saccharose: Andrew Schultz of Grumpys had told me that the Coopers malt extract is too high in dextrins for a pure malt brew, and that some refined sugar would make for a better tasting beer. He could be right: I note that after the previous ale brews have been conditioning for about 6 weeks, the body increases greatly, and they already have quite a high proportion of sugars. It'll be interesting to see the difference.
This was also the first time I had used the bulk malt. On the one hand, it was easier than I thought to pour it into the honey bucket, and using the honey gate was also easier than I thought, but I misjudged the amount that was left dribbling after turning off the gate (I'd guess about 250 g), so I ended up with about 200 g more of extract than expected. My calculation programs helped there, but it meant that I had to add 1.5 l of water to get to the same OG as the other brew. Boiled the Fuggles for 60 minutes in water with sugar and citric acid, forgetting that I really needed more; instead, added more Goldings to the cooled wort (this time done better by adding cooled boiled water). I still forgot to check the temperature before pitching, and discovered to my horror that it was 35°. There are too many differences between the two brews, but hopefully I'll be able to decide what creates which difference in the final beer.
| quantity | ingredient |
| 2 kg | Liquid Wheat Malt |
| 500 g | Pale Malted Barley |
| 250 g | Malted Wheat |
| 250 g | Caramunich Malt |
| 250 g | Munich Malt |
| Hallertau Hops | |
| Hersbrucker Hops | |
| 10 g | Hallertau Dry Hop |
| Wyeast 3068 |
This is pretty much the way Grumpy's published it. I've changed the yeast (they recommend Wyeast 3333), and I'll have to calculate the hopping. I'll also add some more malt extract to increase the volume from their “5 gallons” to 25 litres.
Cooling down is still a problem. Despite everything, I ended up with a wort at 33°. I must buy a beer cooler.
On the Weißbier front, finally came up with a compromise between the two brews I was considering: mainly Coopers Wheat Malt extract, which proved to be a mistake. It's far too dark. Managed to cool things quickly by using ice water, so we should be OK on that front.
The Weißbier that I started on Sunday has finished the primary fermentation. In the process, I noted a distinct change of smell of the exuding gas. Initially it had been nice and fruity, and now it was smelling decidedly sulphurous. Racked the beer, somewhat concerned about infections and other nasties. The yeast smelt decidedly of sulphur, but the raw beer had that Weißbier taste that I was expecting. Presumably this is also what I had at Gordon Biersch in September. This looks like being a real success.
Still, the change of smell got me thinking. Presumably the yeast (Wyeast 3068) consists of a number of different yeasts with different characteristics. If I were to collect the yeast from the secondary fermentation, would it have the same character as the original, or would the late fermenting sulphurous elements predominate? At the moment I don't feel like trying. Instead I'll try a beer with wheat malt instead of Coopers Wheat Malt extract, which is too dark. I'm also curious what a barley-based beer with this yeast would taste like. That might be another one.
Unfortunately, it's relatively easy for a little grain to get in there, and they clog up very easily. The photos here were taken later, when the other tap got itself clogged with nothing more solid than the scum from hop pellets. Here's what it looks like after removing the strainer:
Finding the problem and fixing it was a lot more difficult for the mash, and it took me over an hour. On replacing the manifold, discovered that there are more reasons than uniformity to decide how many slits to put in the manifold: the flow rate was still too low, and I had to remove the thing again and cut three times as many slits in it. After that, mercifully, the sparge worked, and I had no problems with the rest of the brew. In particular, the wort cooler worked nicely, and I was down to pitching temperature in about 20 minutes.
The second brew went better, of course, and I got a really nice, clear wort out of the sparge. I'll be interested to see what effect that has on the flavour of the beer. Certainly the problems have jeopardized my original intention of making two beers which vary only slightly.
It all took a long time. It's probably worth formalizing the time it takes to do a brew like this:
| Time from start | Activity |
| 0:0 | Start mash: 12½ litres of water at 64°, 5 kg malt, resultant temperature 59° |
| 0:2 | Place in oven at 60° |
| 0:10 | Warm to 63° |
| 0:15 | Replace in oven at 63° |
| 1:00 | Warm to 72° |
| 1:10 | Replace in oven at 72° |
| 1:55 | Start sparge |
| 2:10 | (after collecting about 5 litres wort) start boil |
| 2:40 | By now the sparge should be complete, and the wort should be boiling. Add bittering hops. |
| 3:30 | Add aroma hops to boil. |
| 3:40 | Start cooling. |
| 4:00 | Rack half wort to fermenter, start aerating. |
| 4:30 | Rack remaining wort to fermenter, pitch. |
So, a total of about 4½ hours for the operation. Admittedly, it shouldn't require much presence, but it's longer than I expected.
This last batch of beer has been interesting: for the first time ever, I aerated the wort of Brew 28 for over half an hour, and it rewarded me by fermenting nearly twice as fast (and noticeably warmer) than I've ever had before. Brew 29 only got about 10 minutes, after which I had to stop because the froth was crawling out of the fermenter. It get fermented at less than half the rate. I'll have to investigate how to aerate the wort without it foaming out of the fermenter; looks like I'll have to aerate about half at a time.
More recently I tried Brew 4, not recorded on line. It's a Grumpys “Real Ale Masterbrew”. After not drinking any for a while, I now recognize the taste: it's that same horrible chocolate malt (or whatever) that makes me dislike Brew 7, just not as strong. Good thing there are only a couple of bottles left over.
Then I tried Brew 6, also not recorded, a Grumpys “Pale Ale Masterbrew”. Well, that's what I wrote in the (paper) record. It's darker than brew 2, also a “Pale Ale”, though in the latter case I think they use some term like “double hops” to indicate that there are hop pellets in addition to the hopped malt extract.
The good news about this one: it doesn't have this chocolate malt taste. But it tastes thin and uninteresting. Certainly nothing I'd want to go back to.
In the afternoon turned my attention to a temperature logger kit that I had bought from Ozitronics kits, and which I had seen at Linux.conf.au in January. In the process, realized that I had forgotten a lot of common knowledge about electronics components, and that the kit instructions didn't help. Which is the positive pole of an electrolytic capacitor? Which way round does a diode go? Spent some time confirming that my suspicions were correct (the capacitors I have have a marking next to the negative lead, which is also shorter; diodes have a bar at the cathode end, the one that is shown as a bar in the circuit symbol). Didn't take long to put the kit together, but connecting up the temperature sensors, which look like small transistors, is terrible. There just don't seem to be any components that you can use for this sort of thing. I need to find a better solution to this issue, but for the time being just kludged it by soldering things together, along with some lengths of (German) telephone wire, which has the most confusing colour coding I've ever seen: all conductors red, most with varied-spacing blue stripes. The spacing is such that you can't tell them apart without stripping at least 10 cm of the outside insulation, so I ended up using a continuity meter to find the ends. The result works, but looks terrible:
More investigation is require before I can really use these things, but at least I'm getting an output like this:
=== root@sydney (/dev/ttyp1) ~ 21 -> cu -s 2400 -l /dev/cuaa0 Connected. R V1.0 2002-01-06 20:37:37 C 1 0024.25 3 0023.50 4 0024.68 1 0024.25The first number on each line is the sensor number (note from the photo that 2 isn't connected), and the second is the temperature in °C. Looking at the values, it seems that the device uses Fahrenheit internally (resolution 0.10 °F) and converts to °C. We can live with that.
I had plenty of them, so spent some time putting things together. The rest worked nicely with a serial cable with 25 pin connectors at each end, which I was able to connect relatively cleanly. It's sad that I have to resort to this sort of solution rather than to get standard solutions.
The results are more functional than pretty:
Note the position of the temperature sensors:
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It looks as if I'll be able to get better than 0.2° accuracy either way.
Based on my experiences two weeks ago, decided to aerate the wort for a full hour. The problem is foaming: I had to stop the aeration of brew 29 because it was overflowing the fermenter. I had a similar problem making a starter a couple of days ago:
Solved that problem by aerating half the wort each in two fermenters:
We'll see how that goes. First attempts with the temperature control showed a certain amount of oscillation until I tuned the parameters, but then it looked fine:
This shows a period of about 18 hours. Look at the bottom (cyan) line: it shows the cooler (bottom state), idle (middle state) and heater (top state). Initially, of course, it had to cool the wort down from 24° to 19.5°. After that, until about 40% through the time, it was heating and cooling alternately. After changing an overshoot parameter, it went a lot better. Note also that, as the fermentation intensity increases, the need for heating goes away, though the ambient temperature is lower than the wort temperature.
Cations (+ charge) Calcium 50-150 ppm Magnesium 10-30 ppm Sodium 0-150 ppm (but recommends > 70 ppm) Anions (- charge) Sulphate 50-150 ppm for light beers Chloride 0-50 ppm (recommends some)Now the problem is the relative weights of the cations and anions. They almost don't overlap: the anions are heavier. In particular, the ratio of magnesium to sulphate in magnesium sulphate is 4 to 1. I've come up with the following table for my personal use:
| Substance | Molecular | proportions | inverse |
| weight | proportions | ||
| Calcium carbonate | 100 | 0.4 Ca | 2.5 Ca |
| CaCO3 | |||
| Calcium sulphate | |||
| CaSO4.½H2O | 145 | 0.275 Ca | 3.625 Ca |
| 0.66 SO4 | 1.5 SO4 | ||
| Calcium sulphate | 172 | ||
| CaSO4.2H2O | |||
| Magnesium sulphate | 246 | 0.097 Mg | 10.25 Mg |
| MgSO4.7H2O | 0.39 SO4 | 2.56 SO4 | |
| Sodium chloride | 58 | 0.396 Na | 2.52 Na |
| NaCl | 0.603 Cl | 1.657 Cl | |
| Sodium bicarbonate | 84 | 0.274 Na | 3.652 Na |
| NaHCO3 | |||
| Calcium Chloride | |||
| CaCl2.xH2O | |||
| Hydrochloric acid | 36. | 0.97 Cl | 1.03 Cl |
| HCl | |||
| Hydrochloric acid, 30% | 0.29 Cl | 3.43 Cl |
The way this table works is: the “proportions” table tell you what proportion of the substance is the ion in question. The “inverse proportions” tells you how many parts you'll need for one port of the ion.
So: I started out with the following mineral bill:
| Ca | 100 ppm |
| Mg | 20 ppm |
| SO4 | 100 ppm |
| Na | 80 ppm |
| Cl | 100 ppm |
Then this table:
| Substance | ppm | Ca | Mg | SO4 | Na | Cl |
| NaCl | 110 | 20 | 30 | |||
| NaHCO3 | 290 | 60 | ||||
| MgSO4.7H2O | 100 | 20 | 80 |
Round about here, the problem became apparent: I already have all the chloride and half the SO4, and I haven't done any calcium yet. How can I do that?
In the end, I compromised: I used the following:
| Substance | ppm | g/25 l | Ca | Mg | SO4 | Na | Cl |
| NaHCO3 | 291 | 7.28 | 80 | ||||
| MgSO4 | 100 | 2.52 |
Racked . Considering David Logsdon's recommendations, decided to drop the temperature to 17°. The resultant temperature graph was interesting:
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| Enzyme | pH range | pH range | Temperature range | Temperature range |
| Germany | USA | Germany | USA | |
| β-amylase | 5.4—5.6 | 5.0—5.5 | 60—65° | 45—66 |
| α-amylase | 5.6 | 5.3—5.7 | 72—75° | 68—72° |
Sent a message out asking about the discrepancies. The answers should be interesting.
I didn't get many answers, but John Palmer sent a document describing the process in much more detail. It's not exactly a predigested answer, unfortunately.
When I started these two brews, I put some wort into a couple of glasses and left them on the kitchen window sill. Things here are definitely not sterile:
It took them about 5 days to start doing something, and today one (brew 46) was covered in mould, while the other one looked normal. Testing the refractive index, I found that both had attenuated more than the beers I had just bottled: the sample from brew 45 had 8.3% Brix, and brew 46 had 6.4% Brix. I don't suppose it would have been the same if I had kept them at the same temperature. Maybe I should do that next time.
The smell of the brew 45 sample was OK, though I didn't dare try it; earlier it had had a rather rotten (sulphurous?) smell. brew 46 obviously smelt of mould.
The 3068 yeast culture is looking quite happy. I only made about 500 ml of it, so I suppose it's worth stepping up to a litre or so. Then I can have another go at Weißbier next weekend.
Now to work out the best way to dry them. Initially I thought of a cool oven (40°), but I was worried that they might lose what little aroma they have. Decided to leave them to dry out at room temperature, which I suppose could take a couple of days.
In the second brew, used the first of my home-grown hops. This too proved to be an issue: the hops clog up the racking tube. I'll have to think of a solution to this by the next brew day.
In addition had problems with my temperature control stuff. One of the sensors seems to have contact problems, and the software is not handling them well:
It's the red line in the graph, of course. Time for some programming.
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