A photograph is more than just a piece of paper unless you're a chemist from Rochester (and one with no real human consciousness to boot). But to say a photo (B/W, color, whatever) has some sort of independent or inherent "meaning" or "truth" is to be a little more than just a little affected.
Any meaning is created by the viewer of the photo and is heavily dependent on what the viewer brings to the table. Take a Matthew Brady photo. A new photographer fresh from his freshman year intro to photo class sees a shutter speed, an aperture, and a composition judged according to the rule of thirds. A historian looking at the same photo doesn't see the object nature of the photograph itself and looks straight at the referent, trying to glean details about where/when/what and put it in a non-photographic context (unless the making of the photo itself has some historical significance to him...). A descendent of the man pictured in the photo sees his great-great-grandfather Jasper. A re-enactor, like the historian, sees only the referent, but is perhaps focused on a different set of information from the photo--the minutae of his kit and how he looks, and probably establishes a far more personal connection to the referent than a historian would. And, as noted, a chemist or photo-archivist sees paper, emulsion, chemistry, states of degradation, etc.
Point is that a photo is a means of communication, and asking whether b/w or color is more representative of reality is sort of asking like whether a paperback or a hardcover book better represents reality. You can do a lot of things with a photo, you can intend a lot of things for a photo, and ultimately your photo's "meaning" or "truth" is re-determined every time someone looks at it.