Neither do we refer to His Precious Body as “bread.”
From the CCC:
In your OP you stated: “Precious body precious blood here in bread and wine…”
I do not understand why you believe this is heretical, because He truly IS present “here in bread and wine.” The Church has always taught this. The hymn correctly states that truth. Jesus is not only present in the accidents of the bread, but also in the accidents of the wine, which is truly His “precious blood.” When we receive either species (accidents) of bread OR wine, we receive both the body and blood of Our Lord, Jesus. Some folks cannot partake of the bread because of allergies, but they are permitted to partake of the “wine” instead and they receive the entire Christ, not just His blood.
How can He be IN bread, for that matter? The bread no longer exists, either. You are picking straws trying to make a new dogma. IOW, just because you believe St Paul did not say “wine” … we know that Jesus took the wine, saying: “This is the cup of My Blood, the Blood of the new and eternal covenant…” The “cup” is the wine that He blessed and consecrated.
It looks as if you are trying to make scripture conform to Church teaching, rather than trust the Church to teach authoritatively what the scripture means. Try reading John 6:54-57. There is no heresy whatsoever, other than in your misunderstanding.