Peroxide for cleaning taps/tubing

[Dave Puhl]

I was just at a seminar and there they were using peroxide..does anyone here use it and in what strength...

[nace]

i used some 35% peroxide to clean some check valves just to see what would happen. i popped out the ball and let them soak overnight. there was a little creamy residue in some but most were clean looking. i don't have a microscope and i don't plan on trying to culture any bacteria. i have had some soaking all year (that i forgot about) so i will rinse them and see. i really don't expect that anything could live through that stuff. if you get any on your skin, it will burn instsntly. we use it diluted 2 cups to a tub of water to soak in. it pulls infection and soreness out of your body. my wife's vericose viens lightened and got better. i'll let you know about the check valve results. how was it used at the seminar ?

[Dennis H.]

I think is the stuff that was mentioed at an open house last year. I was at a CDL open house and there was a class about tubing and they touched on cleaning. They mentioed that CDL was coming out with a tubing cleaner that will naturally turn to water over time. Chemistry stuff going on there I guess.

I for some reason kept remembering Hydro-peroxide but it could have been straight peroxide.

[DrTimPerkins]

The kill efficacy of hydrogen peroxide isn't terribly high. Due to its high reactivity, hydrogen peroxide is typically shipped in fairly low strength (otherwise it can be quite dangerous), which limits its effectiveness. It is also so reactive that unless a surface is clean, the disinfection of the surface can be fairly low. There are some other things that can be added to it to increase the effectiveness.

Lots of cautions....you don't want to put it on metal surfaces or in metal containers (except aluminum), or put it onto anything organic that can catch fire.

Although it'll degrade to water, you definitely don't want to get hydrogen peroxide in your syrup. It'll create a horribly nasty off-flavor.

[inthewoods]

i use 35% peroxide diluted down to 5% to clean my lines at the end of the season, works very good. i dont know the exact chemistry behind it, but i know it breaks down with time and turns to h2o. you have to be very carefull when handleing not to get on skin, i learned the hard way and turned my hands pure white for two days and lost my finger prints and couldnt grip anything for 6-7 months, i where rubber gloves know.

[Dave Puhl]

It was at a CDL talk last week where I heard about it..and when I asked about the kind ....the response was that we sell it.. I was just going to try the store bought stuff but now I not sure its strong enough or is worth it..as for getting in the syrup..the guy from CDL also stated that it turns back to water in a short time...thanks for all of the replies

[maple flats]

I also use peroxide to clean tubing at the end of the season. I use 35% food grade peroxide and mix it 1 qt to 100 gal water. You can't mix ahead because sun light will break it down quickly. You should not use medical or janitorial grade because they both contain chemicals that preserve it and the chemicals are not compatable with syrup. I may however stop using it because I've read so many that just clean with good water. I do however have about 3/4 of a 15 gal bbl of it. I bought it from a water treatment company. It is in a heavy all black plastic barrel. The barrel was far cheaper per gal. than buying food grade 35% online. That cost $35/gal plus shipping (in 2007). The barrel was about 5x that for 15 gal and no shipping. In water treatment it is used to kill certain bacteria for drinking water and it is metered in at extremely low rates or it would be harmful to humans and animals alike.
As someone said, wear rubber gloves, also goggles and wear an old pair of jeans when using it or you'll ruin a pair unless you like the mod, splotched bleached design. The bleached spots will quickly fail and then you have holes all over. It is powerful stuff, but very effective cleaning tubing!!! For fittings at $.35 each, not worth it, buy new, the extra syrup easily pays for the fittings many times over.
Dave

[philkasza]

Are squirrels more prone to chew on tubing cleaned with peroxide than if they are wash with warm water, or not washed at all?
Thanks Sam

[Dave Puhl]

CDL says that using bleach atracks the squirrels ...and peroxide does not...my thought was on the bacteria in taps and this inturn closes up the tap hole reducing sap flow......I just use hot water..I have an outdoor burner for a wood stove and alls I do is hook the hose to the house hot water tank and flush taps and lines each year and put them all in covered barrels toso sunlight cant get to them...

[ennismaple]

Are you sure they were talking about hydrogen peroxide and not isopropyl alcohol? Isopropyl alcohol is being tried by a number of people I know to wash their tubing because it leaves no residue.

[DrTimPerkins]

Are you sure they were talking about hydrogen peroxide and not isopropyl alcohol? Isopropyl alcohol is being tried by a number of people I know to wash their tubing because it leaves no residue.

There are two problems with any of the typical types of sanitizers, including hydrogen peroxide, isopropyl alcohol, or others. The first is that they do not penetrate biofilms well. Typically for surfaces that need to be sanitized, first you need to clean off any built-up organic (oil, proteins, etc.) or inorganic (minerals, scale) deposits (you don't just dip the greasy pot in a little Clorox solution and consider it "clean" do you?) before you can attempt to sanitize. Biofilms, which are formed by microbes, begin to be produced within minutes, and are not at all easily dislodged. Since we aren't scrubbing the inside of tubing (cleaning), we can only get at what is on the surface. Air-water injected from the bottom of the tubing system was an attempt to dislodge materials (clean), but we know that this is fairly ineffective. So our first real step in the process (cleaning) is already compromised or absent. What we are left with is trying to kill whatever we can. Unfortunately, due to the poor penetration of most sanitizers (including hydrogen peroxide) of the biofilm matrix, there are always going to be survivors living underneath the outermost layer that is killed, and these will rapidly recolonize the surfaces again after the sanitizing treatment is done, especially given the nice warm, near 100% humidity environment in a sealed tubing system in the summertime. It's almost the perfect breeding ground for microbes.

The second issue is that none of these sanitizers have any decent amount of residual action. This is good from a food safety perspective, but bad from the perspective of killing microbes. The sanitizer is there for a very brief time (seconds to minutes perhaps, which is woefully inadequate since studies have shown it can take over an hour to penetrate a moderate biofilm layer) and then are gone. This short time period is often not enough to actually have a very high kill efficacy. The second issue is that there is nothing left afterward (no residual effect) to kill those that do survive the sanitizing procedure, so again, they microbes can repopulate the tubing system very quickly. Most people clean their tubing right at the end of the season, giving the little buggers in your tubing system about 9 months to recolonize the system.

Overall the microbes in the system have almost no impact on the longevity of the tubing, however they do affect the sap yield from the trees, especially those on vacuum systems, through the process of backflow and contamination of your tapholes, thereby inducing taphole "drying" and premature sapflow cessation. That is why we focus on good taphole/tubing sanitation practices, generally through annual replacement of spouts, regular dropline replacement (every 3-6 yrs depending upon several factors), and the use of CV adapters as well as other practices. Are they foolproof....no. Will they help everyone to the same degree...no. Are they economically worth doing....maybe...depends upon your situation.

Now there are some types of sanitizers and/or practices that might actually do a good job sanitizing tubing systems. Unfortunately they typically are either 1) extremely expensive, 2) extremely hazardous, 3) not allowed in food products or 4) illegal to use, and/or 5) all of the above.

Bottom line....will hydrogen peroxide work? Probably will help a little bit. Then again, weren't the equipment dealers all selling isopropyl alcohol a few years ago and saying the same thing? There are research projects (Cornell, Centre Acer, UVM PMRC) that are ongoing and planned on these topics over the next few years. So a great deal more will be known soon, but you have to be a bit patient.

[Dave Puhl]

Wow lots of info ..I guess I will keep using the hot water for now....Thanks Doc....

[DrTimPerkins]

Wow lots of info ..I guess I will keep using the hot water for now....Thanks Doc....

Here's a couple of ways to think about it....

Scenario 1. You put hand sanitizer on your hands. Twenty minutes later.....are your hands still sanitized? Pretty unlikely. Why not....because most sanitizers have no residual action. Once the sanitizer is used up or dried out, it no longer sanitizes. Same thing in the tubing system. The stuff goes through, santizes a little of what it contacts (although not much since the amount of contact and residence time is so brief), but doesn't stick around to continue to function.

Scenario 2. You suck a little bit of alcohol or peroxide down through your dropline (maybe a 1/2 ounce) at the end of the season. Is it truly sanitized? Would you want to cut the tubing open and lick it? Now I realize there are a few daring souls in this bunch (not naming any names, but you know who you are ;))....but most would find that idea fairly unsavory. Well...the tree doesn't want that in its taphole any more than you want it in your mouth.

There are some sanitizers out there that if used properly would kill most of the microbes in your tubing. They are generally illegal to use without a permit and FAR too hazardous (to the maple producer and to the environment) to be used in the maple industry.

[Ragged View]

...Overall the microbes in the system have almost no impact on the longevity of the tubing, however they do affect the sap yield from the trees, especially those on vacuum systems, through the process of backflow and contamination of your tapholes, thereby inducing taphole "drying" and premature sapflow cessation. That is why we focus on good taphole/tubing sanitation practices, generally through annual replacement of spouts, regular dropline replacement (every 3-6 yrs depending upon several factors), and the use of CV adapters as well as other practices. Are they foolproof....no. Will they help everyone to the same degree...no. Are they economically worth doing....maybe...depends upon your situation...

Dr. Tim,
Is it worth the time & effort to flush with water at end of season? Sounds like "no" based on the protocol you describe above. Or perhaps I misinterpret.
Thanks,
Mark