All it really means is keeping food cold so that the items are still safe to eat by the time they're delivered. Gigs have a time limit for a reason, but it’s more critical than ever when delivering frozen, refrigerated and perishable items. When cold items start to heat up to room temperature, bacteria can grow and cause the food to become unsafe.
For this reason, all perishable grocery items must be delivered immediately – no more than 1 hour after picking them up. Bear in mind that any items that must be returned need to be back at the store within the 1-hour window – yet another reason to get to the delivery location as soon as possible. Please keep groceries in a temperature controlled environment.