Enzymatic browning and its inhibition

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.

Apple ~KSh 20–40. Lemon ~KSh 10–20. Vitamin C tablets, Goodlife/MYDAWA ~KSh 200–400.

None.

Apple	1 whole, sliced into 4 pieces
Lemon juice	1-2 tablespoons, enough to coat one slice
Vitamin C tablet	1 tablet, crushed and dissolved in ~2 tablespoons water
Plain water	~1/2 cup, enough to submerge one slice

1
Cut a fresh apple into four similar-sized slices.
2
Leave the first slice untreated on a plate as your control.
3
Dip the second slice in fresh lemon juice, making sure to coat all the cut surfaces.
4
Crush a vitamin C tablet into a small amount of water to dissolve it, then dip the third slice in that solution.
5
Submerge the fourth slice fully in a cup of plain water.
6
Photograph all four slices immediately, then again every 15 minutes for at least one hour, noting how quickly (or whether) browning appears on each.
7
Keep checking for a few more hours to see whether the lemon-treated slice eventually starts browning too, once its coating reaction is used up.

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