Since this is not a true fermented product like a real pickle, it would be safer to say that it should be consumed fairly quickly, within a few days, perhaps stretched out to a week but I would expect the quality to rapidly deteriorate. This is even more the case since this preparation uses fresh lime juice, not vinegar.
The recipe author has some opinions about the product quality in the head note: "I personally prefer to eat this pickle the day it is prepared, as the spices tend to mellow a little and the mint leaves tend to darken over time."
Fair enough.
Rosemary Barnett, if you want an amba that will last longer, look at this one.
http://www.food.com/recipe/amba-a-spicy-and-savory-mango-condiment-280255
From general practice (all pickles) and some specific answers on Indian pickles, expected range is one year - two year - forever (with caveats, as long as enough salt or oil are in the mix, presumably to prevent oxidation and deterioration).
See also some answers here on Indian pickles:
https://www.quora.com/Indian-Cuisine-and-Food-How-long-does-pickle-last-before-getting-spoiled
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3 Comments
The recipe author has some opinions about the product quality in the head note: "I personally prefer to eat this pickle the day it is prepared, as the spices tend to mellow a little and the mint leaves tend to darken over time."
Rosemary Barnett, if you want an amba that will last longer, look at this one.
http://www.food.com/recipe/amba-a-spicy-and-savory-mango-condiment-280255
See also some answers here on Indian pickles:
https://www.quora.com/Indian-Cuisine-and-Food-How-long-does-pickle-last-before-getting-spoiled