How much ascorbate to neutralize one liter of chlorinated tap water?
This is just a very short explanatory note on the article suggested by Greg E..

The reaction between ascorbic acid and hypochlorous acid is as follows:
$$ \ce{C5H5O5CH2OH + HOCl → C5H3O5CH2OH + HCl + H2O}$$
so for 1 mole of hypochlorous acid you need 1 mole of ascorbic acid. This can be recalculated into a mass ratio by the use of their molecular masses:

$$M(\ce{C5H5O5CH2OH})=176\;\text{g/mole}$$
$$M(\ce{HOCl})=52.5\;\text{g/mole}$$
From this we can see that if the molar ratio is $1:1$, the mass ratio is $176:52.5$ which is $3.3:1$ somewhat higher than the article claims. 

I am not exactly sure of the reason, it could be that there is some side reaction of ascorbic acid that also removes some additional hypochlorous acid although I wouldn't know which. Perhaps the article is talking about the amount of ascorbic acid you need to get a concentration which you don't taste anymore?