Iodophor vs. Bleach: Choose Your Poison
Many people come into the store with preconceived ideas about brewing: things they have learned from friends or grandparents, or procedures heard in passing. This is all good, because it often means less that we have to teach them here in the store. But one thing that many people want to do, which I always try to discourage, is sterilize with bleach.
Let me start by saying that when I first started brewing, that was all that we had, and I used bleach very happily for many years. It is not a terrible way to sterilize, but nowadays there is such an easier, better way to go that it seems foolish to use bleach. Let me explain.
Iodophor is an iodine-based sterilizer. The Iodophor we carry at Main Street is a food-grade, restaurant-quality sterilizer. It is also used in the local milk dairies outside of Hillsboro, or so I am told. It is a very safe, benign solution to work with; and without further ado, here are the pros and cons of Bleach and Iodophor.
Bleach should be diluted in water at a rate of about 4 Tablespoons per 5 gallons. The rule of thumb with bleach is that if you splash the water and smell chlorine, it is going to "sterilize" the equipment that you soak in there. Iodophor is diluted at the rate of one Tablespoon per 5 gallons. At these levels, bleach takes 30 minutes to do its job, Iodophor take only a minute or two, and I have gotten away on many occasions with dipping and splashing equipment in the Iodophor for only a few seconds (although I cannot recommend this!). 30 minutes vs. 2 minutes. Round 1 goes to Iodophor.
Bleach needs to be rinsed off after COMPLETELY before coming in contact with beer. Most substances on earth (roses, apple pie, skunks) is detectable to the human nose in a concentration of "parts per million." Chlorine is detectable to us in "parts per billion." This is an order of magnitude greater in sensitivity. What this means is that IF you leave any residual bleach/chlorine behind in your siphon tubes, on your plastic bucket, anywhere you will know it. So, if you do use bleach, you must (after thirty minutes) turn on the hottest water in your bathtub and rinse, rinse, rinse the inside and outside of everything for quite awhile to remove the slimy bleach residues. Iodophor (used at the proper concentrations) is a no-rinse sterilizer. Soak your equipment for a few minutes, pull it out of your Iodophor solution and it is ready to use. (Although I always give fermenters and carboys a quick splash of clean water to get rid of excess iodine puddles at the bottom of them. But in no case do you have to worry about rinsing every square inch of surface like you do with bleach.) Lots of scalding rinsing vs. little to no rinsing. Round 2 goes to Iodophor.
Chlorine is chemically reactive to some metals, particularly stainless steel. This means you CANNOT use bleach or chlorinated cleaners in kegs or chillers or pots or anything metallic. Iodophor is non-reactive all around, no worries. Round 3 - slam dunk - goes to Iodophor.
The cost. Bleach is cheaper, this is true. Iodophor (at its most expensive) costs $5.00 per 4 ounces. It gets much cheaper (per ounce) as you buy larger-sized containers. But that $5.00 vial, diluted down, can produce 40 gallons of sterilizing solution. And by the time you factor in the cost of hot water to rinse the bleach, the cost of your water and sewer bill, the time spent waiting for bleach to sterilize and the hassle of rinsing it off, those few saved pennies are probably lost in the process. Round 4, I call it a tie.
We will always have those that insist on bleach, and this is fine. But for the ease of use that Iodophor offers, I cannot see how anyone can insist it is the better sterilizing solution...