What do you do with leftovers

Babies leftovers. She didn’t want all her food , Half was untouched. Do you save it or chuck it?

ETA: it was just peas & some shredded cheese. I put it i the fridge for dinner time instead. I just had a thought I heard before that if baby’s saliva got on it to dispose?? Or is that in the earlier days. Babe us 8.5 months