It’s not supposed to “symbolize” blood. It is blood. Really and truly, though it still retains the appearance of the accidents.
I think for that reason white wine might in fact be more appropriate in that it more fully underscores the miracle, and the mystery, of the sacrament which converts wine into the blood of Christ, and underscores the fact that the wine is not meant to be a mere symbol, but truly is the blood of Christ, made sacramentally present for us. The red colour may in fact end up confusing less well catechized faithful into thinking that the wine is in fact only a symbol.
That said though, either type of wine is entirely licit for the sacrament. The above is my opinion only.
Not only the Eucharist, but all the sacraments are precisely supposed to symbolize the realities they effect. That is what makes them sacraments. A sacrament that is not a sign is nonsensical. The Catholic Encyclopedia has many definitions of sacrament, all of which include its sign value:
“Signum sacro sanctum efficax gratiae” — a sacrosanct sign producing
grace, is a good, succinct definition of a sacrament of the New Law. Sacrament, in its broadest acceptation, may be defined as an external sign of something sacred. In the twelfth century
Peter Lombard (d. 1164), known as the Master of the Sentences, author of the manual of systematized
theology, gave an accurate definition of a sacrament of the New Law: A sacrament is in such a manner an outward sign of inward
grace that it bears its image (i.e. signifies or represents it) and is its
cause — “Sacramentum proprie dicitur quod ita signum est gratiae Dei, ei invisibilis gratiae forma, ut ipsius imaginem gerat et causa existat” (IV Sent., d.I, n.2). This definition was adopted and perfected by the
medieval Scholastics. From
St. Thomas we have the short but very expressive definition: The sign of a sacred thing in so far as it sanctifies
men - “Signum rei sacrae in quantum est sanctificans homines” (
III.60.2).
Hence it is often argued that red wine accomplishes the sacramental role more effectively because of its closer symbolic valence with the blood both signified and truly present. You’ve established a false dichotomy.