The probiotics are an excellent idea, although they can increase gas initially until your body adapts.
I'd suggest avoiding simple carbs and sugars, carbonated drinks, gum chewing... as well as foods that are known to cause gas like legumes and cruciferous veggies.
Diagnosed with ulcerative colitis spring 1999.
Maintenance dose sulfasalazine. Probiotics, l-glutamine, vitamin D and fish oil caps. George's aloe vera juice. Oregano oil antibiotic, antiviral, antifungal. Mostly grain-free and dairy-free diet. Long-term remission with only minor blips.