Food in shell is French, load being imported (8)
I believe the answer is:
escargot
'food in shell' is the definition.
(French term for a snail as food)
'is french load being imported' is the wordplay.
'is french' becomes 'est' ('is' in French).
'load' becomes 'cargo' (synonyms).
'being imported' indicates putting letters inside.
'est' placed around 'cargo' is 'ESCARGOT'.
(Other definitions for escargot that I've seen before include "Edible snail (from Fr.)" , "French food" , "slow food?" , "One continually moving house" , "mollusc, from Paris" .)