BOULDER, Colo. — “Welcome, pig lovers, and welcome, earthworms!” Woody Tasch bellowed from the stage of the Boulder Theater, where 650 food entrepreneurs and investors had wedged themselves for the opening day of the fourth Slow Money National Gathering.

Mr. Tasch whipped the crowd into a frenzy on Monday morning — shouts of “It’s crazy!” and the random boo and hiss ricocheted through the audience — as he discussed the moral failures of unsustainable corporate farming and financiers struggling to align their urge to buy low and sell high with socially conscious investing.

As venture capitalists increasingly bet on food start-ups, Slow Money, a nonprofit that catalyzes the flow of capital to small and local food enterprises, supports what Mr. Tasch called the heroic grunts: the food producers and their fiduciary counterparts, or “food-ish-iaries,” committed to healing and investing in a broken system, either through manpower or money.