PB& J sandwiches hardly ever get moldy
I remember back in the day when I was in Grade School Mom would pack My Lunch in a brown paper bag. A sandwich with cheese and some meat (Carl Buddig sliced ham, chicken, roast beef, homemade chicken salad) on white bread, chips or pretzel sticks, an apple and I had a Nickel for milk in that little carton. She would make it the night before and put it in the refrigerator until I was on the way out the door to school at 07:30 for the walk to school (uphill both ways) I think we had lunch at 11:00. Never got sick from lunch.
I grew up eating Airline food since Dad worked for AA and We traveled quite a bit. There was food that I didn’t like what it was but I don’t remember ever getting sick from eating it. Back then in the 60’s - 70’s there were one or very few complaints about it IIRC. Back then they even gave Us real flatware with sharp knives !!!