Trying to deliver food so that it travels and arrives looking as good as when it leaves the kitchen is quite a feat at the best of times.
Loading correctly is key, as is driving at a sensible speed with long slow stopping distances and careful maneuvering around corners, i have been the subject of driver rage as i slowed to turn into a venue- all in a days work!!
When the weather is excessively hot, i open up the car about an hour before travelling and about 20 minutes before leaving place ice blocks in cool bags and boxes to chill. I also leave assembly of delicate and susceptible ingredients until the very last minute. In normal circumstances i also make sure there is a fridge on site to put these items in on immediate arrival.
Last year with temperatures at 39 degrees it was the hottest i have ever worked in, it was not the food i was worried about but more the guests well being and thankfully i had in advance suggested the host buy lots of ice to provide cold drinks which were welcomed.
At the other end of the scale, delivering hot food in very cold temperatures becomes a different challenge and speed of packing and unpacking is key.
Thankfully the majority of deliveries are local and therefore not in the car for very long.