A very ancient tradition regards one species to become consecrated by virtue of coming into contact with the other species. This was the case in the Latin Church during the pre-sanctified Mass of Good Friday, and at other times (like last rites). I believe it is St. Bede the Venerable (it’s one of the Anglo-Celtic saints) who records that a certain Irish Saint, when he was going to administer Communion to the dying, had the Body of Christ brought to him and placed it in a chalice of normal wine. He then communed the dying man with both Species (the norm before Trent). I.e., the consecrated Host was mingled in wine, and by virtue of the intinction, the wine is considered to receive consecration and become our Lord’s Blood.
I’m not Roman Catholic (I’m Orthodox), so rules may have changed since Trent. But, before Trent - and still, in the Orthodox Church (whose sacraments Rome now recognizes as valid) - the wine would be considered consecrated when the consecrated host was intincted.
That isn’t to say that the norm is to consecrate both when celebrating a normal Mass. And, any attentive priest should definitely consecrate both in such a Mass. And, if he realizes that he failed to consecrate the wine at some point before the intinction, he should definitely return to the words of consecration over the wine. Someone mentioned that a parish priest did this under similar circumstances, and that is certainly what we Orthodox would do, especially if the Body had not yet been inticted in the chalice. The old Roman Mass used to involve an intiction of the host into the chalice near the “Agnus Dei.” I’m assuming it still does?
The Orthodox Church regularly celebrates “Presanctified Liturgy” throughout the season of Lent. The “Presanctified Liturgy” is a Mass, wherein previously consecrated elements of the Body of Christ are distributed instead of consecrating the Body again. It is understood that when the Body is placed in the chalice at such a pre-sanctified Mass, the wine in the chalice becomes the Blood of Christ without any words of consecration. Some Orthodox Churches will drip a few drops of Christ’s Blood onto the Body when consecrating it beforehand, just “to be sure” that some of the Blood of Christ is present. But some would also point out that these drops of Blood have dried by the time the Body is distributed three days later (on Wednesday Evening’s Mass). The same thing was done in the Latin Church on Good Friday in the past. Perhaps it is still done; I don’t know enough about Latin liturgy after the reformations of Trent or Vatican II.
So, in short: while Trent may have changed the canonical procedures in the Latin Church on this matter, ancient Tradition holds that whenever one element is brought into contact with the other with the clear goal of consecrating it and distributing Communion, it is ipso facto consecrated. One should follow the discipline of one’s rite - but, with the confidence that if a small, unitentional error such as this has been made, all that has been violated is a matter of proper ritual procedure; the Tradition would still hold the wine to become consecrated by virtue of the intinction. This was the procedure in the Latin Church in a few circumstances, especially the presanctified Mass of Good Friday, and is still the custom in the Orthodox Church (and Eastern Catholic churches) during every Wednesday and Friday of Lent. So, don’t worry! Accidents like this happen.
Of course, I’m not saying that just because the wine is consecrated by coming into contact with the Body, one should omit the proper form of Mass under normal circumstances. Priests should always strive to perform the services correctly and with attentive devotion.