What Is Food Grade Hydrogen Peroxide?
That was the question I asked myself when I first read about using food grade hydrogen peroxide to discourage mold from growing on my sunflower microgreen seeds.
Is the peroxide I bought from the drug store so my daughters could clean their pierced ears food grade?
If not, what's the difference? Will it matter since it will evaporate before we eat the microgreens?
What does a bottle of hydrogen peroxide contain?
I wasn't sure, so I took a look at the label on the brown bottle.
What's in Drug Store Hydrogen Peroxide?
I visited several drug stores and pharmacies and didn't find any hydrogen peroxide on the shelves labeled as food grade.
Regardless, I bought a bottle and brought it home to use on some tests.
Let's take a look at the ingredients label and see what this stuff contains besides hydrogen peroxide. Below is the bottle I bought.
Ok, it does say oral use, but it also says not to ingest.
Also, what does debriding actually mean?
What is a Debriding Agent
The definition is this:
Debridement is the medical removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue.
That doesn't really make me want to use it on food. However, it might help clean up seeds.
Hydrogen Peroxide Active and Inactive Ingredients
Here's what our drug store hydrogen peroxide contains.
Well, nothing exciting, only hydrogen peroxide (who would've guessed?) and distilled water to dilute the solution to 3%.
However, notice the word "stabilized" after hydrogen peroxide. Peroxide is unstable, and once exposed to air (by breaking the seal on the bottle), it starts to react and break down into water.
In fact, hydrogen peroxide lasts only 30 to 45 days at peak effectiveness, and after about six months, you should replace it.
What is the Stabilizer?
Here's why I hate our labeling laws. If the peroxide has been stabilized, what has been added? Obviously, the manufacturer or bottler doesn't have to say.
So I did some research.
Here's a list from USP Technologies, under the URL of h2o2.com.
Common stabilizers include:
- Colloidal stannate and sodium pyrophosphate (present at 25 - 250 mg/L) are traditional mainstays.
- Organophosphates (e.g., Monsanto's Dequest products) are increasingly common.
- Nitrate (for pH adjustment and corrosion inhibition) and phosphoric acid (for pH adjustment) also are used.
- Colloidal silicate is used to sequester metals and thereby minimize H2O2 decomposition in specific applications that depend on the bleaching ability of H2O2 in alkali.
Are any of these dangerous? I'm not sure, most likely not in the minimal quantities we use on sunflower seeds.
But still, why take a chance if you don't have too.
What's in Food Grade Hydrogen Peroxide?
Below is the label from Essential Oxygen's hydrogen peroxide bottle (click image to expand - most photos in the article will enlarge if clicked).
We may earn a small commission from the companies mentioned in this post at no additional cost to you. Not all links are connected to affiliate companies.
As you can see, food grade hydrogen peroxide doesn't contain stabilizers.
Using Food Grade Hydrogen Peroxide
There are many concentrations of food grade hydrogen peroxide. We only use the 3% solution.
However, if I were planting a lot of sunflower seeds, or had another use for it in the garden, I wouldn't hesitate to buy a higher concentration and then dilute it with distilled water.
Only because it would be more economical, not because a higher concentration is needed.
We do not recommend using a stronger concentration than 3%. As you will see in a future article on Home Microgreens, the 3% solution worked wonderfully.
Pin the image below to your Pinterest Garden Board!
Don't ingest any hydrogen peroxide, regardless if it's food grade or not.
Here's a link to Poison Control's page on H2O2.
Since peroxide is very unstable, buy the smallest bottle you think will do the job.
When I open the seal on the bottle, I only make the smallest slit possible. This reduces the amount of exposure and may slow down the degradation.
What Hydrogen Peroxide Should You Use?
Since we at Garden Permaculture and Home Microgreens like to test things, we, of course, tried to use the cheaper hydrogen peroxide in the brown bottle along with the food grade solution.
Truthfully, as you can see in the Home Microgreens article, the brown bottle H2O2 didn't work very well to stop fungus from growing on the seeds. Though it did kill fungus if it was sprayed directly on the filaments once the seeds germinated.
We don't think it's worth using anything but food grade hydrogen peroxide. Even if it stores better. Why add possible harmful chemicals to the food you'll, or someone else will eat? Plus, it didn't work as well as the food grade hydrogen peroxide.
We recommend Essential Oxygen 3% Food Grade Hydrogen Peroxide.
As you can see by the testing on Home Microgreens, this hydrogen peroxide works well. You can also buy it in larger sizes if you need more.
The best place to buy it, as we didn't find any food grade peroxide in stores, is at Amazon. Below are affiliate links (no extra cost to you) to the products.