We must first profess our faith in the Eucharist. I have four basic beliefs about this sacrament.
FIRST, I assert that Jesus is really and truly present in this Sacrament. This is not simply a sign or figure of speech, but a literal fact. His is really present.
SECCONDLY, I believe that what was bread and wine has been changed into the Body and Blood of Christ - so that there is no longer such a thing there as brad and wine, existing together with the Body and Blood. All that remain are the appearances of bread and wine. What exists after consecration of the Body and Blood of Christ.
THIRDLY, I believe that the whole Christ, body, blood, soul and divinity, is contained under the appearance of either wine or bread.
FOURTHLY, I believe that this presence is not limited to the liturgical action which causes it, but that the true Body of the Lord remains in the consecrated hosts that are left over and is to be adored as such. These four assertions of faith are derived from the teaching of the Council of Trent. (Canon on the Most Holy Sacrament of the Eucharist, 1-6. Denzinger 355)
THIS BELIEF in the Real Presence has been constant in the Church since the beginning. The Council of Trent formulated the belief only to counteract some other teachings that were contrary to the tradition handed down.
~ Fr. Aloysius Ellacuria, excerpt from here
and more information about Fr. Ellacuria here ~