Sanitation: Tips from the Pros

Kurt Widmer
Widmer Brewing

The three things brewers should not forget when it comes to sanitation are:

  1. Looking clean is not equivalent to actually being clean or sanitary.
  2. There’s no replacement for good hot cleaning chemicals and elbow grease.
  3. Any sanitizing agent should be beer compatible. Frequently people use chlorine. They dilute bleach with water. They are very effective sanitizers, but they leave a residue. If you have to rinse out the residue, what is the point of sanitizing. The water could carry contaminants.

To clean equipment we use 180° F caustic sodium hydroxide. Cleaning takes off any of the proteins from the fermentation that might still be clinging to the side of the tank. The best thing available to a homebrewer is TSP (trisodium phosphate). There’s nothing better than sodium hydroxide but it’s a pretty dangerous product. TSP is a good substitute.

I’m not a big fan of using acids as a cleaning agent. I’m more in tune with using alkaloids such as caustic soda. I don’t think acid cleansers are anywhere near as effective as sodium hydroxide.

To sanitize there’s nothing better than live steam. But not every homebrewer has access to live steam. When we don’t use steam, such as when we sanitize kegs, we use iodophor. We do not rinse that out—as long as you stay under 20 parts per million, then you fall within the FDA guidelines. When we rinse a tank with iodophor, we leave just be the few droplets that cling to the wall of the tank—there would be no accumulation in the bottom of the tank.

When trying to dry off some of the iodophor on the equipment before use, you have to be careful of airborne contaminants. We let our tanks drip dry internally sealed up. We then drain anything out of the bottom of the tank. When I was a homebrewer I put cheesecloth over the carboy and inverted it so it could drip dry but any airborne contaminants would be unlikely to get inside.

During the brewing process there are times homebrewers should be more careful than at others. Homebrewers should make sure that the yeast they pitch does not contain any contaminants. If you use smack packs sterilize the container. Just give it a quick rinse in iodophor.

Cooling is another critical phase. I always set up my system so that once the wort cools it’s in a closed vessel or a relatively closed vessel. I was never really big on the so called open fermentation.

William Foster
Capitol City Brewing

At Capitol City we have a cleaning system where we add water and about a 2 percent solution of a caustic sanitizing agent to begin with. Caustic, which is either in a powdered or liquid form depending on what company you get it from, takes out organic matter or solids such as residual yeast. We follow the caustic with a quick water rinse. We follow that with an acid.

Following the caustic, acid gets rid of the beer stone (also known as calcium oxalate). Beer stone is a buildup similar to a mineral deposit. Beers sometimes leave beer stone, depending on the type of beer and how we treat the water. For example the pale ale takes a little bit harder water. It can sit in the fermenter for quite a while. You will have a little of that beer stone build up.

We follow the acid with a water rinse. We don’t worry about waterborne bacteria and we have a carbon-activated charcoal filter that takes out the chorine. As long as homebrewers have an okay municipal water source, they shouldn’t worry about water rinses either. Some advanced homebrewers will filter the water supply or treat their water in some way or another. That’s not necessary.

A good rule of thumb for any homebrewer is caustic followed by acid and water. But for homebrewing applications, TSP works well as both a cleanser and sanitizing agent. You have a small enough space that you can use your own elbow grease and reach in. When you’re talking about tanks 20 feet high, you don’t want to climb in there. We need to use more chemicals in higher concentrations.

TSP is a bactericide and a fungicide. It will get any bacteria, fungus, and act as a detergent. You should rinse with water after TSP.

It’s good to clean your boil kettle, but superficially clean. In the boil—during the mash process—you use spoons and other equipment. You are sterilizing what you are using in the boiling liquid. A lot of people dip their spoons in a sanitizer before they begin to stir each and every time. I used to do the same thing. There’s nothing wrong with that, but you don’t have to worry that much about the sanitation during this stage. Nothing will survive the boil.

You want to start worrying about sanitation in your transfer, your wort chiller, and then your first and second fermenter. Whatever hose, transfer unit, siphon, spoon, and miscellaneous tool you use after the boil should be sanitized. You can use TSP and a water rinse for that.

One thing to be particularly careful with is any line such as PVC hose or tubing. Hoses need to be free of crevices that can trap contaminants. Deadends or T-clamps need to be taken apart for cleaning after each use. Longer pipe runs should be grouped in shorter circuits to avoid difficulty maintaining proper temperature and pressure needed to remove soil during cleaning. If there are tight bends you can also gets pockets of air (cavitation) that won’t be able to go all the way through the pipe.

Percy Young
Goose Island Brewing Company

We use caustic soda, which is basically sodium hydroxide. This is stuff you don’t really want to use as a homebrewer because it’s pretty harmful to the skin. In addition, it can react pretty violently, particularly when combined with CO2. There are a lot of cases when people will put caustic soda into their fermenters without bleeding off the CO2 and causing implosions. We work with a lot a safety equipment. We also do a lot of rinsing with water. I don’t see a lot of need for homebrewers to use caustic soda.

We also use a food-grade phosphoric acid, which helps sanitation. We also use iodophor sometimes, you might find it called “Micro Clean.” It’s good, but it really stains so we don’t use it all the time. It’s an occasional thing.

Homebrewers can easily get a hold of iodophor, but when I was a homebrewer I used bleach to clean. Sometimes you can get residual taste from the bleach in the beer. It all depends on your method of rinsing. You have to be able to rinse very well.

There are many products you can use for sanitizers, such as B-Brite and iodophors. The important thing is to follow the instructions. Certain cleansers can become sanitizers at higher temperatures. We like to heat up our caustic soda to a little over 160° F because at 163° F for a certain amount of time, caustic soda not only cleans it sanitizes as well.

One of the most difficult challenges for homebrewers is keeping fermenters clean, particularly if you’re using plastic. When you look at the plastic fermenter after you’ve cleaned it you have to realize that looking at things wet is deceiving. The film of water might be hiding something underneath there.

Plastic fermenters can be overused. They tend to wear down. I had a few that took dives but I still used them. I think I paid for it with bad beer in the end.

There are no tricks to cleaning plastic fermenters. I learned my lesson and switched to glass. The plastic can develop nicks and cuts that hold everything from pedeo caucus (SP) to lactobacillus.

Transfer lines can be another area of potential problems. With copper piping you have to be careful about how corrosive your cleanser is. The plastic tubing can harbor a lot of bacteria if they are nicked on the inside or if they stay stained. That can be a problem if you’re using iodophor or something that stains—it might deceive you by hiding other buildup stains.

Issue: December 1995