Here are some of my past posts on the Eucharist and on transubstantiation:
- Common Errors on Accidents, Substance, and the Eucharist
- Understanding Accidents, Substance, and the Eucharist
- Is Jesus Locally Present in the Eucharist?
- Is Jesus Christ physically present in the Eucharist?
- Invalid Consecration of the Eucharist due to Heresy
- Do the molecules of bread and wine change at the consecration of the Eucharist?
- Jimmy Akin’s heresy on Transubstantiation
- More on Jimmy Akin’s heresy against the dogma of Transubstantiation
- Jimmy Akin’s new heresy on transubstantiation
The dogma of transubstantiation defined by the Council of Trent:
The most holy Eucharist has indeed this in common with the rest of the sacraments, that it is a symbol of a sacred thing, and is a visible form of an invisible grace. But there is found in the Eucharist this excellent and unique thing, that the other sacraments have the first power of sanctifying when one uses them, whereas in the Eucharist, before being used, there is the Author Himself of sanctity….
And this faith has ever been in the Church of God, that, immediately after the consecration, the true Body of our Lord, and His true Blood, together with His soul and Divinity, are under the species of bread and wine; but the Body indeed under the species of bread, and the Blood under the species of wine, by the force of the words; but the body itself under the species of wine, and the blood under the species of bread, and the soul under both, by the force of that natural connection and concomitancy whereby the parts of Christ our Lord, who has now risen from the dead to die no more, are united together; and the Divinity, furthermore, on account of the admirable hypostatic union with His body and soul.
by
Ronald L. Conte Jr.
Roman Catholic theologian and
translator of the Catholic Public Domain Version of the Bible.
the reproach of Christ 
Canon 927 says the following regarding the consecration of the Eucharist: “It is absolutely forbidden, even in extreme urgent necessity, to consecrate one matter without the other or even both outside the eucharistic celebration.” Is the prohibition of consecrating one matter without the other or the prohibition of consecrating both outside of the eucharistic celebration a dogma or divine law that must always be observed, or is it a discipline that can be dispensed by the Pope?
Interesting question. I would say that the consecration is valid, but illicit if one is consecrated without the other. Suppose, for example, that a priest consecrates the bread at Mass, then he dies of a sudden stroke before he can consecrate the wine. The consecrated bread remains consecrated, so it is possible. In other words, it is not necessarily an invalid consecration to consecrate one without the other.
Would it be possible to consecrate the Eucharist outside of Mass? Perhaps. The first Eucharist was in the context of a Passover supper; we might consider that event to be a Mass, but it is far and away different from the Mass of today.
So I would answer that the Canon you cite pertains to discipline, and is dispensable. However, the wording “even in extreme urgent necessity” leaves open the possibility that it might be Divine law, rather than merely church law.
If some circumstance made wine unavailable in some regions of the world, the Pope might dispense the law that says both species must be consecrated.