Red cabbage pH indicator (no-heat blender method)

Just examples of where to look and roughly what to expect to pay, get everything from wherever works for you, at whatever price you find.

Red cabbage, Naivas/Chandarana/larger markets ~KSh 80–150/head. Test liquids already in most kitchens.

None.

Red cabbage	2 cups chopped
Water	2 cups (for blending)
Vinegar	~2-3 tablespoons (test liquid)
Lemon juice	~2-3 tablespoons (test liquid)
Baking soda solution	1 tsp baking soda in 1/2 cup water (test liquid)
Soapy water	~2-3 tablespoons (test liquid)
Plain tap water	~2-3 tablespoons (test liquid)

1
Chop roughly 2 cups of red cabbage into small pieces.
2
Blend the cabbage with about 2 cups of water until it becomes a fine purple slurry, no heating is needed.
3
Strain the slurry through a sieve, cheesecloth, or coffee filter into a bowl, collecting the deep purple liquid, this is your pH indicator.
4
Pour a small, equal amount of the indicator into several clear cups.
5
Add a different household liquid to each cup, for example vinegar, lemon juice, a baking-soda solution, soapy water, and plain tap water.
6
Observe the color change in each cup: pink/red signals an acid, staying purple signals neutral, and blue/green signals a base.
7
Rank your tested liquids from most acidic to most basic based on the colors you recorded, and photograph the row of cups together.

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