Preschoolers' appetites increase with growth spurts and decrease when they are tired or excited. Your best approach is to create a quiet time before meals. Present nutritious food in an attractive, simple way, leave it for a reasonable time, then remove it without comment. Do not make judgments about your child's behaviour based on the food eaten. There are some foods my child won't eat.
Many children refuse new foods the first time they are offered.
Take the mystery out of a food by talking about it and by letting your child help prepare it. Encourage tasting and exploring new foods but don't be concerned if the food is still refused. Serve it again another day. Remember that children, like adults, have their likes and dislikes. It is not uncommon for a child to refuse a new food.