Question

why lemon pickle is not stored in aluminium utensils

Answer 1

lemon pickle isn't stored in aluminium utensils as it is acidic in nature. So it reacts with such metals to form toxic substances that aren't suitable for our consumption..
Acid + Metal = Reaction (toxic)

Answer 2

Answer:

$\huge\rm\orange{Answer:-}$

No, we cannot store lemon pickle in an aluminium utensil because aluminium is a metal and metals readily react with acids to produce hydrogen. When aluminium comes in contact with lemon, which is acidic, would react to give hydrogen and the pickles will be spoiled.