The wine is real wine, usually sweet, usually red as the wine color adds symbolism to Jesus' Christ's blood which was shed when he died for us. Do this in remembrance of me. These three kings played into the Christmas story by bringing kingly gifts of gold, frankincense, and myrrh. God is the symbol of kings. Frankincense is burned as an offering for the gods.
Myrrh is a special oil of anointing for kings and for royal burials.
In the Episcopal church, Epiphany also marks two other events - Jesus' baptism in the river Jordan by John the Baptist, and the story of Jesus' first miracle of turning water into wine at the wedding feast in Canaan which was his first public miracle as recorded in the Bible. Thus the Epiphany has symbols of water, light, royalty, the Holy Spirit, and wine. Epiphany is loaded with symbolism. The Dove is a symbol of both the Holy Spirit and the dove which brought Noah the olive branch after the great flood. The dove with flames is frequently used to represent the Holy Spirit, resting on the shoulders of believers at the time of Pentecost.