ROBERTO CASANUEVA and I are loitering outside Whole Foods in the Pearl District, spending the morning doing the most "Portland" task imaginable: loading up his bike with 150 pounds of organic food to deliver to homeless shelters.

But it's not just any bike! It's a European-made electric-assist cargo tricycle, complete with a custom-made giant box on back that can haul up to 600 pounds. Casanueva is arguably the city's slowest bike messenger, one of seven part-timers employed by B-Line, a bicycle delivery service that has replaced traditional delivery trucks for some Portland businesses, dropping off everything from dry cleaning to Thanksgiving turkeys.

This morning, Tuesday November 16, the scruffy-faced Casanueva was up at 5 am delivering 300 pounds of Dave's Killer Bread and assorted produce from a downtown warehouse to Bijou Café, Prasad, and Whole Foods. Now, having served the high-end clients and left with an empty cargo hold, Casanueva can stock up on nearly expired veggies and truck them over to homeless shelters.

"Mornin' brother," Casanueva says to the produce-stacker, pushing through the big double-doors leading to the backroom bowels of Whole Foods. It smells like fish. Back in a storeroom, Casanueva finds a pushcart waiting for him, loaded down with seven cardboard boxes. It's a treasure trove totaling 153 pounds: day-old fresh guacamole and salsa, lovely radishes, and way too many boxes of grapes.

Whole Foods donates some of its nearly expired food to the Oregon Food Bank, but picking it up, trucking it out to the food bank headquarters, and distributing it back out to shelters can take nearly a week. Casanueva loads up his trike and hauls the load just eight blocks to Sisters of the Road, the homeless café. Like always, a crowd is gathered outside the café and when they see Casanueva pull up, three guys rush over to help unload.

"Holy guacamole!" shouts one helper, spying the box of guacamole, previously priced at $5.99 a pound. Sisters of the Road funnels B-Line $800 a month in donations for the roughly 2,600 pounds of food it delivers—a far cheaper rate than buying food from traditional sources.

"It's radically changed our menu," says kitchen co-manager Bob Davis. "It's really helped us out because we can invest our food money more wisely." In the past year and a half, Sisters has pushed to make the $4 lunches it serves more healthy—they've gone from serving mostly meat sauce over rice with frozen veggies to a menu that's 70 percent organic with lots of greens.

B-Line started up a pilot program of the homeless food-delivery program, called B-Shares, four months ago. It officially launches this week. San Francisco transplant Franklin Jones started B-Line itself back in late 2008 and now its fleet of three trikes delivers for about 15 clients. There's plenty of well-intentioned hippie sentiment to go around in Portland, but B-Shares—surprise, surprise—has a business model: In addition to the nominal fee for delivering to Sisters, the business is asking Portlanders to sponsor a B-Share meal. Thanks to the low delivery costs (literally, Casanueva rolling downhill from Whole Foods to downtown homeless shelters) B-Shares can deliver enough food to make a meal for only 50 cents.

Over at Sisters, Davis and the ragtag volunteers unload the Whole Foods veggies in seconds. There's actually too much food—too many grapes to handle. The café can adapt to a certain amount of fresh fruit overload, but they send Casanueva back on the road with two boxes stuffed with grapes to deliver to Blanchet House.

"We rarely served fresh fruits and veggies before. They were too expensive," says Davis. "Dining with dignity doesn't mean feeding people from the bottom of the food chain."