Monday, March 26, 2012

Bottle blues

Every time I have to wash, rinse, sanitize, fill, and cap 60-some odd bottles I wish I were kegging.

Don't get me wrong: There are few joys in the life of a homebrewer that equal the sudden thrill of finding a perfectly good, dark brown, non-screwtop bottle with an easily removable label. In my neck of the woods the local Vienna Lager (Goldstar) comes in these bottles, and it is one of the greatest justifications for the continued existence of that beer (Though truth be told, as far as Vienna lagers go, Goldstar is one of the better examples of the mass-produced breed). I look for bottles everywhere: I have scoped out every recycling bin around my office, and I know which ones have empty beer bottles and on what day. My coworkers have gotten used to seeing a crate of empty bottles in the corner of the office waiting to be taken home, and my friends have learned to put bottles neatly in bags for me. I am the bottle king of my little domain.

But it's a lot of work. Especially if one suffers from a lethal combination of fishing bottles from the trash (often with dried residue and fungus inside) and a compulsion for cleanliness and sanitation that would make a clean-room worker weep with joy. Before any bottle of mine gets filled it had been rinsed out between 6 to 8 times, scrubbed with a dedicated bottle brush, sanitized with contact sanitizer (including the mouth and a few centimeters on the outside), and filled on top of the sanitizer foam. Multiply that by 60 bottles for an average 20L batch, and you'll easily understand why I wasn't that upset when my latest batch of cider turned out sour. - At least it meant I didn't have to bottle it!

So I'd love to keg, but it's not really a realistic option.

For one thing, I don't drink enough. I drink somewhere in the neighborhood of one liter per week. I still have bottles of a Pilsner I brewed in August (and it's still good, which I attribute to the anal-retentive sanitation described above), and practically every other beer too. At that rate, I would be able to use a keg maybe two or three times a year (assuming I just drink from that keg). Hardly worth it.

For another thing, I don't have the cooling. I "only" have the fermentation fridge (I say only in quotations because I'm well aware that many home brewers don't have that, and I count myself blessed to have a wife who doesn't mind sticking a fridge in the livingroom so long as she gets to decorate it). Kegs need to be kept at serving temperatures (not strictly true, of course, but the alternative is an inline cooler, which is another piece of equipment I don't have) where as beer needs to ferment at temperatures much higher. They can't live in the same fridge.

Actually that's not true: I could dedicate my fridge as a keg/lagering fridge and brew ales and lagers based on the ambient temperatures. But I loth to do that. So much of the character of beer hinges on precise temperature control that I would hate to lose that ability just to save some effort.

And kegs have their own problems: They don't transport well (If you want to take some beer over to friends you have to bottle it). They're expensive (compared to the free bottles I get). They don't age well (I have an "archive" of past beers I brewed, so I can taste how they change over time). And they require a lot of extra equipment (CO2, lines, taps, etc).

All of these reasons mean that I will stay with bottles in the foreseeable future. Maybe one day I'll have a large walk-in cooler in the basement and thirty taps lining the walls of the livingroom. But as it is, whenever I have a beer that's ready to leave the fermenter I will be putting it in bottles, and just wishing I were kegging...

Tuesday, March 13, 2012

Dialing in your process

When you first start brewing it's all guesswork.

There's a lot of numbers involved in brewing. Efficiency, volume, gravity, boiloff, time, and many many more. You need to know these things when you brew, but you'll only know them when you start brewing, so you guess. You use rules of thumb, estimates, and calculations to achieve approximate numbers that you can use to estimate your results. And then you brew with those numbers. If you're lucky, they're close enough to true values that you end up with decent beer. When you're just starting, "decent beer" is great, and you get convinced it's the best beer you've ever tasted. So that's fine.

As you grow more proficient as a brewer, though, you start noticing certain things. The OG is consistently a little low, the color is a little off, the attenuation is not what you were looking for, the beer is decent but it's not great, etc. At first you attribute this to mistakes in the particular batch, then you start blaming inconsistencies in the process. But after you improve the process, and repeat it consistently, it becomes a nagging feeling that you're missing something else. Eventually, you start looking at the underlying assumptions that you base your process on, and try to modify those assumptions to fit the factors of your particular system. This is called "Dialing in" your process.

For me the trigger was realizing that my OG is consistently two points lower than the recipe expected. This mean that the water to sugar ratio in my wort was slightly off. IE, I either had too much water, which meant my boiloff wasn't as much as I thought, or I didn't have as much sugar, which meant that the mash efficiency wasn't quite what I thought. Of the two, boiloff is the easier to measure, and is relatively constant. So lets start there.

There's two ways (that I can think of) to measure boiloff:
The first involves simply measuring how much liquid you had at the beginning of the boil, versus how much you have at the end. The difference is the stuff that boiled off. Simple in theory, but can have unforeseen problems. For example: If you use an immersion chiller, like I do, you need to put it into your wort 10-15 minutes before the end of the boil in order to sanitize it. Since you have to measure at the end of the boil you will either have to allow for the volume of the chiller (bigger than it looks) or take the chiller out (which negates the point of putting it in to sanitize in the first place. ) You can measure after you chill, of course, so long as you account for the shrinkage due to temperature drop. In my case, since I measure with a ruler stuck in the wort, this was not an option. I simply wasn't going to stick an un-sanitized, sugar coated metal rod into my wort.

The second method to measure the volume is calculating posthumously. That is, using the numbers you get to calculate what the boiloff was. This works as following: Lets say after I finished my sparge with 32Liters of 1.042 wort. After I boiled and cooled I sampled my wort and came up with an OG of 1.050. The amount of sugar did not change during the boil, only the amount of water. Therefore I can say this (Ov*Pg)/Og = Fv Where Ov is Original volume, Pg is preboil gravity, Og is Original gravity (at end of boil) and Fv is final volume. In this case: (32*42)/50=26.88 Given that my original volume was 32, I lost 5.22L of liquid during the boil, or roughly 16%.

The beauty of this method is that you can apply it retroactively. I take notes every time I brew, and I know my start volume, start gravity, and final gravity for each batch. By taking the last few batches, running them through this simple calculation, and averaging the result, I can get a pretty accurate measure of my boiloff. One I know that, I can go back to my calculations and figure out if I had too much water, or not enough sugar. Adjust, brew, test, adjust again, and so on until the numbers are consistent.

The sad part about this is that I'm going to go through all the trouble of dialing in my process, and then I'm going to change it again when I go HERMS this summer. But then again: I'll still be using the same kettle once I go HERMS, so doing this calibration now will make it much easier to isolate problems with the new setup down the road. So I guess it's worth it.