It might be worth tracking your calories/macros for a bit to check you're getting enough energy intake and protein(hurrdurrwheredovegansgetbrotein?), I use http://www.myfitnesspal.com/ because it syncs with trainingpeaks & strava, the UI is pretty good too.
I think you're calling tuna salad something different than what I call it. I was raised that tuna salad was tuna fish, mayo, maybe some diced celery, and seasonings. There's no way to eat around the "salad" in "tuna salad". Here is what tuna salad is, at least in my region of the US: http://allrecipes.com/recipe/barbies-tuna-salad/
And this is what we call "chicken salad", at least in my region of my country: http://www.momswhothink.com/chicken-recipes/chicken-salad-recipe.html/
I can only guess you're taking some sort of tuna salad recipe and adding it to something else... what do you mean by "the salad"? Vegetables? Beans, onions, salad dressing? But without having any idea what the something else is, sorry but I can't suggest what might be causing the gas.
A general suggestion when a person has a reaction to a dish: try eating one ingredient in the dish. If that doesn't trigger the problem, try some later with the 2nd ingredient added. And so on until you've slowly added in the additional ingredients one by one.
Vegetarians do not eat fish. It's a pet peeve of mine because the moment I tell a waitress I can't eat meat, she suggests the salmon or the fish sticks. But a fish is an animal and therefore it is meat. :-) I think you're thinking of a pescetarian? Or perhaps one of those meat-eaters who are just avoiding red meats?
Non-mobile: http://www.amazon.com/dp/1623363586/ref=mp_s_a_1_1?qid=1429960144&sr=8-1&keywords=thug+kitchen#
^That's ^why ^I'm ^here, ^I ^don't ^judge ^you. ^PM ^/u/xl0 ^if ^I'm ^causing ^any ^trouble. ^WUT?
Here's a fairly inexpensive alternative that you can get on-line. You take it with the first bite and it prevents the gas from forming. http://www.amazon.com/Bean-zyme-Anti-Gas-Digestive-Supplement-Shipping/dp/B000CQY9EK/ref=cm_cr_pr_pb_t/179-4308929-6982407
I'm not the OP, but I've personally bought it from the store before. I normally buy the Ancient Harvest brand. Click on that link to see it on Amazon (they have lots of different ones -- spaghetti, rotelle, farfalle, etc).
Upvote for the Veganomicon recommendation. It was the first veggie cook book I ever bought and it is absolutely wonderful for beginners and experienced cooks alike. The first few chapters are dedicated to instructions on how to prepare just about every kind of grain, legume and vegetable you'll commonly come across. The recipes in the book are also delicious and for the most part quick and simple to prepare. Definitely give this one a try.
Peta wrote a cookbook of only recipes which can be made in the microwave: <http://www.amazon.com/PETAs-Vegan-College-Cookbook-Delicious/dp/1402218850/ref=sr_1_1?ie=UTF8&s=books&qid=1266097407&sr=8-1>
Also, if you have access to a fridge, keep fake lunchmeat and bread around; pretty easy to make a sandwich.
Rice cookers are the greatest invention ever; rice is retardedly cheap and a rice cooker means you need no skill whatsoever to cook it; many come with a steamer on top so you can steam vegetables at the same time as cooking the rice. At my university you're allowed to keep them in the dorm.
Buy this book: Mark Bittman's "How to Cook Everything Vegetarian" [amazon page]
It alone has nudged my frustration with my girlfriend's vegetarianism up into appreciation levels.
If you want a book that's both entertaining and informative I would recommend Skinny Bastard. Also see Skinny Bastard About. It will help you with diet and lifestyle along with supporting your choice to go vegetarian. I'd let you borrow mine if I could. Best of luck!
I would add The Mediterranean Vegan Kitchen to that list. I know the Moosewood cookbook isn't a vegan cookbook. I don't know about the other ones listed, but the Mediterranean Vegan Kitchen is, and the recipes are SO good and there are SO many.
I use a slightly modified version of the recipe from Professional Vegetarian Cooking.
dry: 2 c vital wheat gluten; 1/2 c white flour
wet: 2 T tamari; 3/4 c vegetable juice cocktail (I never have this, so I squirt about 1 to 1 1/2 T of ketchup in the bottom of a liquid measuring cup, fill to the 3/4 c line with water, and whisk it up); 1/2 c water; 4 drops liquid smoke
Mix the dry stuff separately, mix the wet stuff separately, then mix everything in a bowl. Knead until it's a homogeneous blob, then let rest for 15 minutes. Sculpt it into a log, and slice into "steaks" or strips with a serrated knife. Bring a large pot of stock* to a boil, add the seitan, and let it come to a boil again. Simmer at a medium-low temperature for about an hour. Now cook it like it's meat! I think that this is a pretty good recipe, although keep in mind seitan generally won't have much taste anyway until you season it AFTER all of the boiling is done. One of my favorite ways to cook it is to pan-sear it in strips with extra virgin olive oil, tamari, and umeboshi vinegar (cook until all of the liquid from the tamari and ume is gone).
*I don't bother with premade stock because if you cook with fresh ingredients enough, you will have everything you need to make it at home. Just save carrot tops/peels, celery tops, onion peels, garlic peels, parsley stems, mushroom stems, bell pepper innards, etc until you have enough to fill a pasta cooking sized pot about 1/3 to 1/2 full. Jack up the flavor by adding a couple garlic cloves and a sliced onion. Once I reused ginger that had been used to make ginger beer; stock making is pretty forgiving. Fill it to about 3/4 full with water, bring it to a boil, and let it simmer for about 45 minutes. Strain it well and compost the solids.