Republished from BrewingTechniques' November/December 1995.

The Ghosts of Beers Past

A: The most likely source of your problem is your draft beer lines. They are made of plastic (polypropylene and/or vinyl), which can absorb odors. The only other possibility is residue in your tank(s) or kegs, but that would cause other problems - namely, infections. I assume that your CIP procedures are working for you.

If the draft lines are the source, you will probably notice a stronger fruit aroma when the beer has been sitting in the lines for a while (for example, early in the morning before the pub opens). If you draw a few pints in succession, you will get to beer that has been sitting in the serving tank or keg, and it will taste all right, because it traveled through the lines for only a very short time on its way to the tap.

Fixing this problem can be difficult. The first thing to do is clean the affected lines with a strong line cleaner solution. However, this may not be enough. The next step is to try soaking the lines. You can probably rig up some way to pump or siphon a solution into the affected lines. Then close them up and let them sit for a day or two. Of course, this means you may have to 86 one of your beers for a couple of days. After the soak, flush out the lines with plenty of water and then put your beer back on line.

As a soaking solution, I recommend a low-pH chlorine sanitizer such as FrmChlor (Farm Chem, Washington, Missouri; most chemical companies that sell to small breweries have a similar product). This stuff has the oxidizing power of chlorine but the low pH (5-6) means it is not nearly as corrosive as hypochlorite-based products. In fact, the manufacturer recommends allowing it to dry on tank walls after use. I have soaked stainless clamps and other fittings in it for several days and have seen no signs of corrosion. When I use it in CIP applications, however, I still rinse the tank out with plenty of water after sanitizing - not because I expect corrosion, but because chlorine is bad for beer flavor.

Steam Source Needed for a Small Jacketed Kettle

A: The way microbrewers do it is to hire an experienced, competent (one hopes) contractor to assemble and install their steam generator and piping. The kettle manufacturer specifies the size of the boiler to be adequate to deliver enough BTUs to the jackets to get a boil in a reasonable time. (It takes a lot more heat to bring wort to a boil than to maintain the boil once it is reached.)

The basic arrangement is a closed loop with the steam (for a small kettle) at 5-15 psi. The steam is piped into the jackets of the kettle under its own pressure. Inside the jackets it condenses to water, which flows by gravity into a small collector tank. The collector feeds a pump that is turned on and off by a float switch. The pump sends the condensate back to a reservoir that feeds the boiler. The whole arrangement can be quite efficient, but it requires a lot of plumbing and numerous safety devices to meet code. As I mentioned in a previous column, relative to direct fire, steam is always much more expensive to install on a small kettle.

I suppose it is possible that, with a steam generator grossly oversized for your kettle and no pressure-regulating devices of any kind, you could feed steam into the jackets faster than the condensate could run out, and might even build up enough pressure to crack the jackets. The easiest way to prevent this would be to fit a ball valve in your steam line (the simplest type of regulator) along with a pressure gauge. The only problem is, all this does is shift the pressure buildup from the steam jackets to the boiler, which must in any case be fitted with an automatic pressure relief valve to be safe.

Do not, I repeat, do not attempt to jury-rig a steam generator that is not equipped with a pressure relief valve! All commercial steam generators have such valves, but they are also set up with a pressure sensor that shuts off the gas burner when the steam pressure rises to a preset value. Fortunately, modern pressure cookers are similarly equipped with a relief valve, and also have rocking-weight pressure regulators, which works by blowing off steam rather than regulating the heat.

Some pressure cooker regulators can be set for 5, 10, or 15 psi. If you use one of these I suggest trying 5 psi for a start and see how long it takes to get a batch of wort to boil (do a trial run with water). Go to a higher pressure if 5 psi does not do the job.

Remember you will turn on your steam as soon as you have a few inches of wort in the kettle, and also that the wort will be coming into the kettle at 150-170°F (66-77°C). Most brewers try to regulate their steam so that the kettle boils as soon as all the wort is collected. In my case, the best I can do with 13 psi steam, running all jackets wide open while the kettle is filling, is to bring the wort to a boil about 10 minutes after I finish collecting it. Then I have to close the valve on the side jacket almost completely to avoid a boilover. The bottom jacket stays wide open.

One observation about your proposed jury-rig: It will be a one-way system because there is no way to recirculate the condensed steam back to your improvised boiler. The condensate will just have to go down the drain. This means there is the possibility of running out of water during the wort collection and boiling step. Again, your trial run should allow you to calculate how much water will be consumed.

As for equipping the kettle with a burner, forget it. Low pressure steam is at most 250°F (121°C). There is no way a jacket built for steam will hold up under a gas flame.

A note for other interested readers: Many commercial kitchens use steam-heated soup kettles. Most are smaller than 60 gal, and the small ones are often self-contained; that is, the boiler and all pressure regulating and safety equipment are built into the kettle unit. Both because of this simplicity and because 60 gal is an awful lot of homebrew, I feel that one of these smaller units would be better for a deluxe home brewery than the big kettle discussed above. Steam is very nice to work with, but it presents some serious engineering problems that I, for one, would leave to an experienced professional.

Bottling Techniques

Second, since I started using 22-oz bottles I seem to get a lot more foam when I bottle. I use the same bottle filler and I haven't changed my priming.

Third, how much headspace should I leave in my bottles?

A: First of all, you can fill your bottles while they are still wet. You should let them cool to room temperature before filling, though. To speed up the cooling, open the dishwasher door when the heat-dry cycle is finished, and just leave the bottles standing upside down in the racks with the door open. I know somebody is going to object, but I did this for years and never had a problem - and my kitchen was no cleaner than yours.

Second, I suspect with the bigger bottles you are getting more splashing at the beginning of the fill. It sounds like you have one of those fillers with a spring-loaded valve in the tip. They tend to cause a lot of splashing. This is bad because it aerates the beer.

I suggest you get rid of the filler and just use a plastic hose to fill the bottles. To control the flow, use your thumb or one of those plastic tubing crimpers (many homebrew supply stores now carry them). With a little practice you will get a lot less agitation and aeration than you have now. Also, by using the hose, you can fill the bottle more because, as the beer level rises, you can raise the end of the hose too, keeping it just below the surface of the beer. (For further tips on bottling, see Don Put's column on pages xx-yy of this issue.)

Third, the recent thinking on bottle headspace is that you don't need it - at least, not any appreciable amount. Filling them as much as you can, you will still have a few milliliters of headspace under your bottle caps, and that is plenty. It used to be thought that a certain minimum amount of headspace was needed, for various reasons, but I've seen a number of homebrews that were bottled with no headspace, and the brewers reported no problems.

Is a Thermal Well Necessary?

A: I would definitely go with the thermal well. Every microbrewery kettle or tank that I have ever seen uses a thermal well, if for no other reason than to ensure that the entire assembly is leakproof. If the thermal well makes the idea too expensive, just do what most home brewers do and dunk the thermometer probe into the mash or wort when you need to take a reading. A thermal well will not affect the accuracy of the thermometer, but it will affect the speed with which it responds to temperature changes.