Why does the pH of blood not alter after eating pickle

Why does the pH of blood not alter after eating pickle  

A pickle is a food preserved in vinegar (ethanoic acid). Pickles generally have a sharp, acidic flavour in consequence of the acid preservative. Many systems - especially living cells - require their pH to be maintained over a very restricted range in order to prevent catastrophic damage to the cell. Enzymes and proteins denature, for example, if the pH deviates by more than a fraction. Traces of the food we eat are readily detected in the blood quite soon after eating, so why does the concentration in the blood remain constant, rather than dropping substantially with the additional acid in our diet  

In a similar way, blood does not change its pH because it contains suitable concentrations of carbonic acid and bicarbonate ion, which act as a buffer, as below. 

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