Apples are a low-carbon food and also good for us, says Mike Berners-Lee in his book How Bad Are Bananas? The Carbon Footprint of Everything.
If you pluck the apple from your garden it has Zero carbon footprint. It rises to 10 g. CO2e local and seasonal. It rises to 150 g. CO2e if shipped, cold stored and inefficiently produced.
Apples mostly arrive by boat rather than planes so are carbon friendly.
But what we can all remember is to also buy the most misshapen fruits and vegetables we can get because that encourages the sellers not to throw them out, before they ever reach the shops. They are as good as the others and should not be added to the gruesome waste of everything in the consumerist market says Mike.