If you are feeding him flake food, he will likely do the spitting out thing less and less, as he realizes he can easily digest whole bites. I have a betta in 1 of my 5 fully stocked tanks, and he, as well as almost all the other fish, spit the food out to break it up. However, all of the bigger fish, Including the betta, eventually stop doing it to flake food. I'm sure your betta is perfectly fine. Bettas are not usually picky eaters.
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