Make Red Cabbage PH Indicator For About a Dollar

[massproducer]

This is something that I have been doing now for a little while every time my Ph pen goes wonky, plus it is a fun little thing that you can do with your kids to give them a basic science lesson.


First thing that we need is a head of red cabbage. This costs about a dollar at a local grocery store, and we need a good knife and cutting board.

 

[massproducer]

Next we need to peel off the outer layer or two of the cabbage as this could have have been exposed to chemicals and I just prefer to do this with most of my produce.

 

[massproducer]

Next we have to cut up the cabbage into small peices or you can put it into a blender to pulverize it. I just usually cut it into small cubes and find that this works fine.

After it is cut put it into a small-medium sized sauce pan / pot, with enough water to just cover the cabbage. Heat the mixture slowly to boil.

 

[massproducer]

Let the mixture gently boil for about 15 - 20 minutes.

 

[massproducer]

Next strain the mixture through a coffee filter or metal filter, or a strainer with a coffee filter. Using the coffee filter has it benefits as it can be used as a ph strip once it dries.

 

[massproducer]

Let the strained cabbage juice cool, you can put it in the fridge or just let it cool at room temp, whatever works for you.

When its cool enough put the solution into smaller dropper bottles or small containers and continue cooling.

 

[massproducer]

Next we wanna check and see if this stuff actually works. Get some things with well known ph's, things like Milk, Baking soda and Lemon juice and put a little of each in a small container and add a bit of the cabbage juice with a dropper or just just a spoon, bit you only need to use a little, around 3 drops, sometimes a little more.

Wow, we see a change.

Milk has a PH of about 6
Lemon juice are 2.3ish
Baking soda around 8

 

[massproducer]

Here are a few charts that show the Ph colors when using this as a Ph indicator.


Full Red , pH = 2
Red-violet , pH = 4
Full violet , pH = 6
Blue-violet, 7 (neutral)
Full blue , pH = 7.5
Blue-green , pH = 9
Green-blue , pH = 10
Full Green , pH = 12


Another:

cherry red 1-2
cerise 3
plum 4
royal purple 5
blue purple 6
blue 7
blue green 8
emerald green 9-10
grass green 10-11
lime green 12-13
yellow 14

 

[massproducer]

The reason that this works is because of the chemical Anthocyanin, which... yes if you remember the discussion on purple buds...is the same chemical that makes our buds purple.

Anthocyanin has the ablity to naturally respond to different ph levels by changing its pigmentation.

While this will never replace our Ph pens it is pretty cool and basically as reliable as the drops you buy in hydro stores, once you understand its color charting.

 

[massproducer]

Here are a few more tests


First picture is my hydro solutions Ph, which is a lighter violet color, because it is just about 6, it is around 5.8ish


Second Picture is pure tap water, it is hard to see it good but it is a light blue color, light a strong darker sky blue because my tap has a Ph of around 7

 

[screwdriver]

I like the idea. Maybe boil up the whole cabbage, condense it and just use a couple drops mixed with your sample?

 

[massproducer]

I like the idea. Maybe boil up the whole cabbage, condense it and just use a couple drops mixed with your sample?

You got it, but it is best to cut up the cabbage good. You dont really need to use the whole cabbage, just as much as you need. The water you are boiling the cabbage in, will be your PH indicator solution. Some will boil away but basically the amount of water you are boiling in means you will have that much solution, as long as the water is only to the to of the cabbage, it will be concentrated enough to work great

 

[slowmo77]

so this will work on the run off from my soil right?

 

[massproducer]

yup it will work the same as other ph indicator solutions

 

[mojosat]

I have been told that this works with blackberries too. It's making lithmus (sp) paper right?

 

[thief]

very cool thanks. i like red cabbage but generally end up with 1/2 a head extra. bet i can use it now

 

[ChatNoir]

Good DIY guide! I can use excess cabbage to make PH indicator while half of it will go into my salad XD

 

[massproducer]

Yup, it works with a lot of different flowers, fruit and veggies, anything that has a significant amount of Anthocyanin. So basically if you have a very purple or blue flower, fruit or veggie then there is a very good chance that it contains Anthocyanin, and should work

I have been told that this works with blackberries too. It's making lithmus (sp) paper right?

 

[Tater]

Cool man you should post this in the DIY and put a link to it in the contest thread. Nice one, I'm gonna try this.

 

[massproducer]

Thanks Tater... I am going to ask one of the mods to move it over to DIY, I just wanted people to see it first.