lemon, amla and orange all have citric acids. then what is the reason of change of taste?

Lemon, amla and orange all have citric acids but the concentration of citric acid in three of them is different. Also, there are other components present in these fruits which make their taste different like lemon also contains tartaric acid while orange does not. The different composition of acids in these fruits is 

Lemons contains  Citric, malic, tartaric and oxalic acids

Orange contains Citric, malic and oxalic acids.

Amla contains Citric, malic, shikimic and quinic acids.