There is no transubstantiation in the text of 1Corinthians 11.
After explaining what was received from Christ Paul then summarizes:
“For as often as you eat this bread and drink this cup, you proclaim the Lord’s death till He comes.”
You are trying to find here more than what is revealed. Paul calls it bread after explaining the Lord’s Supper.
And yes Paul tells us the Corinthians were making a mockery and mess of a sacred gathering of the Body of Christ His church.
Read it again. Harmonize it with John, Matthew, Luke, Hebrews, and Revelation. It seems to me you should know what the Protestants and Evangelicals do with the ordinance is not genuine, just a pale shadow. The restorationist movements may try to hold it once a year during a Passover Seder and this also falls short.