Now as they were eating, Jesus took bread, and after blessing it broke it and gave it to the disciples, and said, "Take, eat; this is my body." And he took a cup, and when he had given thanks he gave it to them, saying, "Drink of it, all of you, for this is my blood of the covenant, which is poured out for many for the forgiveness of sins. I tell you I will not drink again of this fruit of the vine until that day when I drink it new with you in my Father’s kingdom." (Matthew 26:26-28).
In discussing the Westminster Confession's teaching on the Lord's Supper, Robert Letham adds this footnote, which calls into question the practice of many Evangelical churches,
we note that the elements appointed by the Lord Jesus are "bread and wine" and that the right to determine these rests with him alone, and not with the temperance movement of the nineteenth century. While Jesus changed the water into wine, the temperance movement changed wine into grape juice concentrate [or Ribena]. No one has any right to change the elements of the Lord's Supper, any more than water may be replaced in baptism by orange juice. To do this is to usurp the authority of Christ. (The Westminster Assembly: Reading its theology in historical context, P&R, 2009, p. 351, n. 76).