Figuring Out My Food Sensitivities After GJ Tube Surgery

how can i figure out what foods my gut may be sensitive to? i am getting surgery for a GJ tube so i can finally have stable nutrition, but i do wonder if it's certain foods that are making my symptoms worse besides just gastroparesis & other stuff. i get gut pain a lot and i have been struggling with constipation since i was a baby, according to my mom. my plan for after surgery i am going to work on my nutrition and figure out what i need most and what sensitivities i may have. me and my family already eat organic, but organic alone isn't going to help any other food sensitivities besides non-organic ones like dyes and alike. if you've been on a similar path before i would love your advice 💙