Dog Gas Help! Food and treat suggestions?

I have and Australian shepherd and a lab mix. They have both been a little gy on nutro puppy sensitive stomach and iams puppy chow (on right now), but it gets HORRIBLE when they are at dog training cles because of the treats. My lab will ONLY eat pup-peroni treats, so I train them both with these treats, and by the end of the cl, I see some of the other owners dry-heaving because the smell is so bad. Since I need to give them lots of treats for training, is there a good treat that won't cause gas and any picky dog will want? I"m not real concerned about the food, but if there is a food that will illuminate their gas altogether, I may switch. Thanks!