Can tawny port be substituted for the ruby variety in a recipe?
The difference between tawny and ruby port lies in the aging process. Before it is bottled, tawny port spends at least two years (and as many as 40 years) in wooden barrels, where it picks up a caramel color and toasty, nutty flavors. Ruby port, on the other hand, is typically aged for only two years and spends little or no time in wood, so it retains a vibrant red color and possesses a more straightforward, fruity character. Ruby port is generally used in cooking for two reasons: First, it tends to be less expensive than tawny, and second, its brilliant red hue is thought to add visual appeal. When we sampled each kind of port on its own, the differences were apparent, but would they be so obvious when each wine was used in a recipe?
In caramelized onions, a pan sauce, and raspberry sorbet, we found that the nuances of flavor we had noted in the tawny port were pretty much lost in cooking or—in the case of the sorbet—obscured by the assertive berry flavor. And the color difference ended up not making such a difference after all; each of the finished dishes boasted a lovely rosy color.
The bottom line: If you don’t mind sacrificing some of your expensive tipple, go ahead and use tawny port instead of ruby.