FYI, here is "chapter and verse" from the Committee on the Liturgy,
United States Conference of Catholic Bishops
"Chapter VI
The Requisites for the Celebration of Mass
I. The Bread and Wine for Celebating the Eucharist
319. Following the example of Christ, the Church has always used bread and wine with water to celebrate the Lord's Supper.
320. The bread for celebrating the Eucharist must be made only from wheat, must be recently baked, and, according to the ancient tradition of the Latin Church, must be unleavened.
321. The meaning of the sign demands that the material for the Eucharistic celebration truly have the appearance of food. It is therefore expedient that the eucharistic bread, even though unleavened and baked in the traditional shape, be made in such a way that the priest at Mass with a congregation is able in practice to break it into parts for distribution to at least some of the faithful. Small hosts are, however, in no way ruled out when the number of those receiving Holy Communion or other pastoral needs require it. The action of the fraction or breaking of bread, which gave its name to the Eucharist in apostolic times, will bring out more clearly the force and importance of the sign of unity of all in the one bread, and of the sign of charity by the fact that the one bread is distributed among the brothers and sisters.
322. The wine for the eucharistic celebration must be from the fruit of the grapevine (cf. Lk 22:18), natural, and unadulterated, that is, without admixture of extraneous substances.
323. Diligent care should be taken to ensure that the bread and wine intended for the Eucharist are kept in a perfect state of conservation: that is, that the wine does not turn to vinegar nor the bread spoil or become too hard to be broken easily.
324. If the priest notices after the consecration or as he receives Communion that not wine but only water was poured into the chalice, he pours the water into some container, then pours wine with water into the chalice and consecrates it. He says only the part of the institution narrative related to the consecration of the chalice, without being obliged to consecrate the bread again."