If you leave the new food and that is his option to eat, he will eat it. The key now to the dog eating what you want him to eat may be hunger. If he gets hungry enough, he will eat it.
Try not feeding him for a day and then give him the ration of 25% new food and 75% old food. See if he leaves any then. Feeding him outside will help because he doesn't have the option of leaving the new food to go beg at the table. He can eat or not eat. He'll eat.
You've had plenty of advice regarding the switch and can read back through this thread for all the great advice. I did a week on 25/75, a week on 50/50, and a week on 75/25 when I switched from Meow Mix to 4Health (a TSC feed with actual meat as the first ingredients). A significant change in the quality of nutrition of the foods will need more time to adjust.
That all said, you said you bop the dog on the nose when he begs. I started using a spray bottle with 50/50 white vinegar and water. The vinegar is strong enough to get in an eye and make a sting, but dilute enough that it's not doing any damage (believe it or not, I tested this on myself first). If your dog starts to associate begging at the table with a bad sting in his eye, he'll quit cold turkey and never turn back
Good luck John!! Sounds like you are doing the absolute best for your dog.
Try not feeding him for a day and then give him the ration of 25% new food and 75% old food. See if he leaves any then. Feeding him outside will help because he doesn't have the option of leaving the new food to go beg at the table. He can eat or not eat. He'll eat.
You've had plenty of advice regarding the switch and can read back through this thread for all the great advice. I did a week on 25/75, a week on 50/50, and a week on 75/25 when I switched from Meow Mix to 4Health (a TSC feed with actual meat as the first ingredients). A significant change in the quality of nutrition of the foods will need more time to adjust.
That all said, you said you bop the dog on the nose when he begs. I started using a spray bottle with 50/50 white vinegar and water. The vinegar is strong enough to get in an eye and make a sting, but dilute enough that it's not doing any damage (believe it or not, I tested this on myself first). If your dog starts to associate begging at the table with a bad sting in his eye, he'll quit cold turkey and never turn back

Good luck John!! Sounds like you are doing the absolute best for your dog.