My father will eat a few spoonfulls at meal time and sometimes in-between meals. After a few spoonfuls he either spits out the food or clamps his mouth shut, even his favorite foods. He father developed a bacterial infection about two weeks ago and has taken antibotics for 10 days. Because the infection has not completely cleared, he will be taking the antibiotic for another 10 days. I believe there is some correlation between the infection/antibiotics and the loss of appetite. But at this point, I don't know what more I can do to encourage him to eat. I'm supplementing with Boost nutritional shake. But it's a fight to get him to drink much of anything.
I wouldn't be as worried about the food as I would be about possible dehydration. Can you get him to drink anything? Not thick, sweet nutritional shakes but water? Juice? Will he take some applesauce?
I would call the Dr. Try not to force food on him and push fluids like water and juice instead. Many elderly people lose their appetite and lose weight because food doesn't taste good to them anymore, or it has no taste at all. Make a deal with him. You'll stop trying to get him to eat IF he'll drink water and juice. Then talk to the Dr. and see what happens. If he's not hungry you can't make him eat.
My Mother in-law had that same problem your discribing.
She stopped eating and losing alot of weight.Her doctor became worried about how much weight she lost and so did the family.Her doctor prescribed medication for depression.It worked but sad for the family to see her all drugged up on head meds.The head meds made her look so bad.Walking around like a zombie with her jaw hanging low like if she was over medicated.They did later get her meds under control.She is eating now.My advise is medication for depression.Take her to a doctor.