I got a lot of mileage out of this product:
It is a food mill that simply grinds table food up easily so you can feed it to your baby. It is inexpensive, easy to clean & can take it with you. No more worries of large chunks of food!
He may be wary of new textures. Make sure he is hungry when you feed him, he will be more inclined to eat different foods.
One last thought, is he doing other things developmentally, like learning how to pull up or walk? Babies frequently put aside an achieved skill to concentrate on one they are trying to master. Perhaps standing in his crib is a lot more important to him than eating new stuff.
Hang in there, you guys will get it sorted out!