Preheat the oven to 350 degrees F (175 degrees C).
Mix ground beef, bread crumbs, bell peppers, onion, egg, 1/3 cup ketchup, 1/4 cup pineapple preserves, 1/4 cup brown sugar, garlic powder, and Worcestershire sauce in a food processor until combined; put into a bread pan.
Bake in the preheated oven for 30 minutes.
Stir 1/3 cup ketchup, 1/4 cup pineapple preserves, and 1/4 cup brown sugar together in a bowl; pour over meatloaf.
Continue baking until no longer pink in the center, about 20 minutes more. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C).