Due to a very high metabolism, ferrets should have access to food and water 24/7. In one end and out the other in 3-4 hrs. Therefore every 3-4 hours they need to eat and drink, no way round that.
Good quality dried ferret food should always be available. (I use a mix of Vitalin and Beaphar Care+). With regards to meat, give them what they will eat within 8 an hour period during the summer, (dusk til dawn to keep the flies off), if they don't eat all the meat, give them less, all gone, give a bit more. Winter months, as much as they will take.
How old is the hob? They can be chubby as