Killinger
Well-Known Member
I've been using Oxiclean for my general cleaning and StarSan for sanitizing for a while. I was recently browsing the Oxiclean website and noticed the ph is 11. Star San, of course, is an acid (ph ~3).
With those stats in the back of my mind, I went to work cleaning and sanitizing some equipment. As I was running the Star San out of the carboy, I remembered that there had been some residual Oxiclean in the bottom when I dumped the sanitizer on top. I wondered if the ph of the Star San had been knocked out of the effective zone by the additional base in solution. So I tested the ph coming out of the carboy: 4.
Star San must be 3 or lower to be effective, right?
So, I ran a dilution "experiment". I took my premixed Oxiclean solution (don't know the ph or the ratio of powder to water, but I'd guess it was 1 scoop to 5 gallons) and premixed Star San (ph ~2.9) and added 1/2 ounce Oxiclean to 8 oz Star San. My ph sticks only go up to 4.4, but it was off that chart.
I continued diluting until it got into the measurable ph zone of my sticks. At a ratio of 1:32, the ph was 3.6. At 1:40, the ph was about 3.
So, at a ratio of 1:32, the solution would be outside the range of effectiveness of the sanitizer. This equates to 1/2 cup Oxiclean per gallon of Star San.
I've never had an infection, but I think I will rinse better between cleaning and sanitizing in the future.
Am I over thinking this? Not thinking at all?
With those stats in the back of my mind, I went to work cleaning and sanitizing some equipment. As I was running the Star San out of the carboy, I remembered that there had been some residual Oxiclean in the bottom when I dumped the sanitizer on top. I wondered if the ph of the Star San had been knocked out of the effective zone by the additional base in solution. So I tested the ph coming out of the carboy: 4.
Star San must be 3 or lower to be effective, right?
So, I ran a dilution "experiment". I took my premixed Oxiclean solution (don't know the ph or the ratio of powder to water, but I'd guess it was 1 scoop to 5 gallons) and premixed Star San (ph ~2.9) and added 1/2 ounce Oxiclean to 8 oz Star San. My ph sticks only go up to 4.4, but it was off that chart.
I continued diluting until it got into the measurable ph zone of my sticks. At a ratio of 1:32, the ph was 3.6. At 1:40, the ph was about 3.
So, at a ratio of 1:32, the solution would be outside the range of effectiveness of the sanitizer. This equates to 1/2 cup Oxiclean per gallon of Star San.
I've never had an infection, but I think I will rinse better between cleaning and sanitizing in the future.
Am I over thinking this? Not thinking at all?