What is potassium phosphate E340

It is a chemical compound. Potassium salts of phosphoric acid.

Potassium phosphates are divided into:

E340 (i) Monopotassium dihydrogen phosphate
E340 (ii) Dipotassium monohydrogen phosphate
E340 (iii) Tripotassium phosphate

What is it for?

Used in agriculture as fertilizer when you want to make the culture phosphorus and potassium without nitrogen or when you want to control and slow down the vegetative growth of the crop.

In the food sector it is an acidity regulator.