What declaration was made about the Eucharist at the Council of Trent?

The declaration made about the Eucharist at the Council of Trent affirmed transubstantiation as the Church's teaching. This doctrine holds that during the celebration of the Eucharist, the bread and wine used in the sacrament become the actual body and blood of Christ while retaining their appearances of bread and wine. The affirmation of transubstantiation was significant because it clarified the Catholic Church's stance against Protestant Reformation views, which often questioned or denied this belief. The Council of Trent also sought to address various practices and theological issues arising from the Reformation, establishing a clear and definitive Catholic understanding of the Eucharist that remains influential to this day. This emphasis on transubstantiation was pivotal in reinforcing the belief in the real presence of Christ in the Eucharist, central to Catholic doctrine and worship.