I also think it would be worth your while to get some of those long Q-tips at the drugstore (if you can find them) and to test the issue after you take a bath or shower. I apologize for the graphic explanation, but when you are sure the exterior of the opening of the vagina is fresh and clean, spread the lips apart and stick the Q-tip in, and then taste it. A lot of the time, the smell (presumably the bacteria) is on the outside of the lips and not inside the vaginal canal at all, and the Q-tip will just smell or taste like cucumbers.
That's a good point Anniebrooke has made. I have seen information thought too on the taste of vaginal secretions changing. It can be diet related I've read. And there is something called cytolytic vaginosis that could also be the cause. I can give you more info if you would like. Let me know what you think!
Are you sure it was vaginal secretions that you were tasting, and not just bacteria from around the area outside the vagina? Those can get smells from sweat and foods and other things.