Shortage of animal produce in vehicle -- one wouldn't want it! (5)
I believe the answer is:
vegan
'one wouldn't want it' is the definition.
I can't tell whether this definition defines the answer.
'shortage of animal produce in vehicle' is the wordplay.
'shortage of animal produce' becomes 'eg' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in' is an insertion indicator.
'vehicle' becomes 'van' (van is a kind of vehicle).
'eg' going into 'van' is 'VEGAN'.
Can you help me to learn more?
(Other definitions for vegan that I've seen before include "Person refraining from using animal products in any way" , "Person neither eating nor using anything animal" , "Person refraining from eating animal products" , "One not eating or using animal products" , "One not eating animals" .)