Is the humble sandwich a climate change culprit?

Is the humble sandwich a climate change culprit?:
"Scientists at the University of Manchester have found a surprising global warming culprit – sandwiches.
In the first study of its kind, the researchers carried out an in-depth audit of various sandwiches throughout their life cycles and found the triangular meals could be responsible for the equivalent annual carbon emissions of 8.6 million cars in Britain alone.
...What the researchers found was that not all sandwiches are created equal and that some varieties have larger carbon footprints than others.
...According to the team, a number of factors affect the sandwich's carbon footprint. Ingredients is one of them, with items like meat in general and pork in particular, cheese, prawns, lettuce, and tomatoes being particularly large footprint culprits..."