Experimental light beer

After the relatively heavy Weissbier and the screwed up SNPA clone, I wanted to try out a light beer. The goal was a drinkable beer with around 3% ABV. I wanted to go with a standard mash program, not Springmaischverfahren (where you pretty much skip the maltose rest and go straight to 72°C). At first I was going to go for a light Weissbier as I have some of the stripped Gutmann yeast in the fridge. In the end I decided to go for a bottom fermenting lager - a kind of light Schankbier.

Given that something like this can go really wrong really fast, I decided to try out a small mash first. The goal was about 7l of beer. For small, experimental brews I already had bought a 15l pot that can be used on a normal induction/ceramic/gas hob, like in any kitchen. I got a big net curtain at IKEA to try the BIAB ("Brew In A Bag") process. Here, you mash in the net curtain in the pot. When the mash is done, you lift the mash up in the curtain. The wort remains behind. This actually worked quite well. I was able to hit my goal of about 8.5 Brix. I had about 9l of wort. It was pretty cloudy though, as could be expected from BIAB.

Boiling, cooling and adding yeast was the same as any other beer, except that I had to take care not to add too much hops. I was aiming for 23 IBU but then decided to stop around 19 because light beers don't have the malt background to counteract hops - meaning that even 23 IBU would come across as very bitter. The beer was supposed to be something like a Munich Helles, so it didn't have to be too bitter anyway.

Since yesterday it is fermenting at 10°C. I worked out that the Stammwürze was almost exactly 8°P (perfect landing). Currently we are at 6.4°P, so something is happening. I'll leave it ferment away until it stops. It tastes very sweet right now, so hopefully it will dry up as time goes by. I'll have to deal with the cloudiness afterwards too. Some Biersol and gelatine will sort it out no doubt.

Triticum Cervisia Citri

SNPA Clone that probably won't be

Time for another blog post about a brew. Since my last post about the Samba Pale Ale, there was an Oktoberfestbier, a stout brewed from extract and an extremely good five corn stout, brewed from mash. Today (Feb 15th) Sven and I decided that we'd try out the new equipment and brew 50l of a SNPA (Sierra Nevada Pale Ale) clone - i.e. a nicely hopped pale ale, with a decent full bodiness and a bernstein colour.

I used a recipe from Maische Malz und Mehr which had some fairly good reviews. I had to change it to suit 50l of wort and I also had to change the hops to suit what I had. I went with Simcoe shortly after boiling, Perle in the middle of the boiling, Citra towards the end, and then a full 100g of Cascade right at flame out.

However, things were not to come as expected. The recipe wanted almost 10kg of malt with 48l of water for the mash. This was no problem for the new Schengler 70l pot, but we suspected even then that we'd have a problem with läutern. We did. The Thermoport cannot hold anywhere near that amount. We ended up collecting the first 40l of wort in the fermentation keg so there would be room in the Thermoport for more of the mash. We eventually did manage to get the job done. Even though we thought we'd have very little room in the 70l pot if we were to use the entire Nachguss in the recipe, we did actually end up using almost a full Silvercrest full. After läutern we ended up with 67l of wort in the Schengler, at about 15 brix - also substantially higher than what the recipe requested. It was becoming obvious even before cooking hops, that we would not be hitting the SNPA recipe. It was more likely going to become an IPA with a much higher Stammwürze and (probably) higher IBU than the 37 of the SNPA.

While adding the hops, we decided to try without using hop sacks. I'm not sure this was such a great idea - I think that the hops diffuse more oil into the wort if they are not in a sack, but the result is a very cloudy wort (more than likely protein). Anyway, after cooking the hops, adding 4l of boiling water (to compensate for what disappeared in steam) and whirlpooling, we piped about 40l of wort into the 60l fermentation keg and the rest (about 18l) into a 30l fermentation keg, meaning we will more than likely have about 58l of beer. After cooling down to about 22°C, we added the yeast (Safale S05). The kegs are downstairs at about 17°C waiting for the yeast to start working.

By way of summary, it wasn't a bad brew day, but a lot of things could have went smoother. The biggest issue was overestimating what can be done with a 38 Thermoport. If we aim for 40l of beer each time instead of 50l (or 58l like what we ended up with), it would probably be significantly easier to process.

Samba Pale Ale

Yesterday I brewed 21l of Samba Pale Ale. This is a recipe I got from http://maischemalzundmehr.de. It is based on a recipe that came from a german guy living in Brazil. The goal is to brew a light summer beer, which is not too bitter (relatively low IBU) and which has a bit of sweetness left after fermentation. The ingredients are fairly standard to a point (Munich malt, Pilsner malt, Cara Hell) but there is also oat flakes, polenta and corn flakes in the mix - meaning this is not a beer you could say was brewed per the Reinheitsgebot.

I had spectators for the first hour, during the mashing. Wolfi and Edith wanted to have a look at the procedure. The mashing went quite well - mainly due to the recipe's simplicity. Heat water to 68°C and chuck in all the malt in one go. Keep it heating for 90 minutes, then do an iodine test and heat up to 78°C. After 90 minutes, my iodine test was fine, so I heated to 78°C and kept it there for 10 minutes. Then I transferred everything from the Silvercrest to the Läuterbottich.

There were some comments to the recipe which said that Läutern did not go well - probably due to the polenta. I had absolutely no issue with Läutern, however. After about 4l, the wort was clear. It looked a bit watery, but otherwise fine. It tasted very sweet. Läutern took about an hour, after which I had 24l of wort back in the Silvercrest, on top of 17g Amarillo hops. The 24l were at 10.5 brix - which was a bit lower than anticipated, but I did use 15l of water for mashing instead of 13l, and I used about 14l of water for läutern as well, so this was to be expected.

I boiled the hops for 90 minutes, after which I had about 21.5l of wort left. I did add a further 3g of Amarillo hops 10 minutes before I switched the heat off. I then put the lid on the Silvercrest and left it alone for 15 minutes. After the rest period (where convections die down), I did a whirlpool and piped the wort into the fermentation tank. I was surprised that the Trubkegel at the bottom of the Silvercrest was so small. Once in the fermentation tank, I saw I had forgotten to run the wort through the Sputnik filter, so I piped back into my filling bucket. I used the opportunity to cool the wort down to 22°C as well, then I piped it back into the fermentation keg, through the sputnik filter.

Then I added the yeast, which I had rehydrated that morning and put the keg into the guest room, which was about 23°C. This was probably not the best idea - the core temperature of the beer was then about 25°C, which is too high. The yeast can still thrive in it, but at that temperature it will produce too many sweet, fruity aromas. Today (16 hours later), I moved the keg down to the cellar, at about 18°C. Before doing so, I took a sample with the refractometer. The raw reading was 9.8 brix, which - using the Terril formula is:

Scheinbarer Restextrakt:	5.9°Plato
Tatsächlicher Restextrakt:	6.9°Plato
Scheinbarer Endvergärungsgrad:	49%
Tatsächlicher Endvergärungsgrad:	40%
Alkoholgehalt:	2.4 Gew.% bzw. 3 Vol.%

After one week cooling

This is what the beer looks like after one week in the fridge. It looks ready and it tastes quite good already. I still think it will benefit significantly from more time though. It still has a bit of a 'wild' aftertaste. The foam is good at the start but it starts to dissipate quite quickly. Having said that, I noticed that the standard Taufkirchner beer has a foam that also falls away quickly too. I'm not too concerned about it. A Klosterbier isn't renowned for having a lot of stable foam anyway. Drinking it out of the bottle actually seems to produce a better taste, which I can't explain. Possibly because of the CO2 bottleneck.

Speaking of CO2, the beer has settled a lot since last week - where it was fizzy like coke. This week it is much more like a beer. I'm still hoping it'll settle a bit more. We'll see next week. In the meantime I bought a PartyStar Deluxe keg dispenser for the 5l kegs (a tap that uses small CO2 cartridges - you can see it in action here) and a couple of empty 5l kegs. Filling the kegs goes much faster than filling bottles. I reckon per 20l brew I could easily fill 2x5l into kegs and put the rest into bottles. 

Bottle fermentation over - time for cooling

After 48 hours at 6°C

The beer has now been bottle fermenting (what you'd call Nachgärung in german) for a week at about 22°C (in my office). In case you missed the previous post, the idea of the bottle fermentation is that the beer builds up CO2 in a closed environment. The CO2 can't escape (it's in a bottle), so the beer gets fizzy. And how do you create the CO2? Well, when yeast is fed with sugar it breaks the sugar down into alcohol and CO2 (in about equal parts). So when the main fermentation (in the keg) is over, you basically have flat beer (as the CO2 escapes). When bottling each bottle gets a little sugar and the remaining yeast (in suspension) in the beer takes care of the rest. The aim is that you can decide beforehand how fizzy the beer should be (Weizenbier is typically fizzier than, say Kellerbier) and going on the temperature you can figure out how much sugar you need per litre of beer. More experienced brewers don't use sugar at all - they tap off Jungbier before it is finished fermenting (i.e. there is still sugar in it which can be coverted to alcohol and CO2) and keep it separately, in the fridge. In german it is called the Speise. Before bottling, the Jungbier is piped onto the Speise and mixed in. This is actually how it is supposed to be done. The method with sugar is a bit of a workaround (incidentally, the new Reinheitsgebot actually allows this for top fermenting beers). There is also a method called Grünschlauchen, which means bottling before the beer is finished fermenting in the keg. Grünschlauchen means you really have to keep an eye on the rest sugar though - and you run the risk of either flat beer or (worse) bottle bombs (where there is too much sugar left in the Jungbier).

My beer is now in the fridge since yesterday, at about 6°C. One bottle was in since the day before, for testing. I tried some of it last night (the glass in the picture is 100ml - perfect for testing). It still has a bit of a wild taste and definitely needs a couple of weeks in the cold. I was also quite surprised to see how much CO2 it had developed. I'm not sure that a Klosterbier should be fizzy - it seems like a beer that should be drunk out of a Steinkrug and shouldn't have that much gas. It was good to see that between yesterday and today the foam got a bit more stable. It's too soon yet to decide if the foam didn't work out (I'd need to check the log of the mashing to see why).

Other than that, there is now nothing to do except wait. From the 500ml bottle I kept as a sampler, I'll try 100ml every night. Next weekend, the beer should have settled down somewhat, though I expect it will be at least two weeks before it will be properly 'drinkable'.

Bottled and ready

Yesterday, we bottled the beer that had been fermenting since the previous Sunday. The rule of thumb to adhere to before bottling is that the main fermentation should be over as evidenced by no activity in the fermentation keg for at least three days. 'Activity' could be seen as CO2 escape (the blubbering) or, to be more exact, the rest sugar level. To determine the rest sugar in the beer you can use either a hygrometer (the archimedes principle) or you can use a refractometer. I bought a refractometer because it means you lose less beer. If you use a hygrometer you have to tap off 200ml of beer every time (a couple of times a day). With a refractometer you only need a drop or two. The refractometer measures how refraction of light as it passes from one material into another. It is measured in Brix (after the guy who invented it). Since last Wednesday my rest sugar level was 7.2 Brix (which works out at about 2,4°P after a rather complicated mathematical excursion which eliminates the effect that the alcohol in the beer has on the refraction).

So, there you have it - about 20l of home made beer "Klosterbier". It turned out to be a darker kind of beer (probably because I dumped the Farbmalz in right at the beginning rather than 10 minutes before the end of the mashing) - not full a 'dunkles' but certainly in that direction. It will also be Naturtrüb (cloudy) - I don't think it is possible to get a really clear Klosterbier. Now, the beer ferments again at 20°C in the bottles, for about a week. This "recreates" the CO2 in the beer (I want about 5g/l). Then the beer goes into the fridge at as close to 0°C as possible, to diffuse the CO2 into liquid (the colder, the better). After at least a week, (the longer the better), the beer can be moved into a normal fridge, somewhere around 6-8°C.