In my experience, high fiberous foods, eggs, and protein powder are the fart causes. Simply eating a lot is a fart causer too - I think its just destiny when bulking
But per wikipedia, http://en.wikipedia.org/wiki/Flatulence:
"Flatulence-producing foods are typically high in certain polysaccharides (especially oligosaccharides such as inulin) and include beans, lentils, dairy products, onions, garlic, scallions, leeks, radishes, sweet potatoes, cashews, Jerusalem artichokes, oats, wheat, yeast in breads, and other vegetables. Cauliflower, Broccoli, cabbage and other cruciferous vegetables that belong to the Brassica family are commonly reputed to not only increase flatulence, but to increase the pungency of the flatus. In beans, endogenous gases seem to arise from complex oligosaccharide (carbohydrates) that are particularly resistant to digestion by mammals, but which are readily digestible by microorganisms that inhabit the digestive tract. These oligosaccharides pass through the upper intestine largely unchanged, and when these reach the lower intestine, bacteria feed on them, producing copious amounts of flatus. In the case of those with lactose intolerance, intestinal bacteria feeding on lactose can give rise to excessive gas production when milk or lactose-containing substances have been consumed....
Most starches, including potatoes, corn, noodles, and wheat, produce gas as they are broken down in the large intestine. Rice is the only starch that does not cause gas."