One poster mentioned the Didache…but the Didache doesn’t necessarily “prove” the “real presence” or that it was seen as 'body and blood"…but echos back to Passover…
The Eucharist – The Cup – The Bread
1 And concerning the Eucharist, hold Eucharist thus: 2 First concerning the Cup, "We give thanks to thee, our Father, for the Holy Vine of David thy child, which, thou didst make known to us through Jesus thy child; to thee be glory for ever."
3 And concerning the broken Bread: "We give thee thanks, our Father, for the life and knowledge which thou didst make known to us through Jesus thy Child. To thee be glory for ever.
4 As this broken bread was scattered upon the mountains, but was brought together and became one, so let thy Church be gathered together from the ends of the earth into thy Kingdom, for thine is the glory and the power through Jesus Christ for ever."
5 But let none eat or drink of your Eucharist except those who have been baptised in the Lord’s Name. For concerning this also did the Lord say, “Give not that which is holy to the dogs.”
The final prayer in the Eucharist
1 But after you are satisfied with food, thus give thanks: 2 "We give thanks to thee, O Holy Father, for thy Holy Name which thou didst make to tabernacle in our hearts, and for the knowledge and faith and immortality which thou didst make known to us through Jesus thy Child. To thee be glory for ever. 3 Thou, Lord Almighty, didst create all things for thy Name’s sake, and didst give food and drink to men for their enjoyment, that they might give thanks to thee, but us hast thou blessed with spiritual food and drink and eternal light through thy Child. 4 Above all we give thanks to thee for that thou art mighty. To thee be glory for ever.
5 Remember, Lord, thy Church, to deliver it from all evil and to make it perfect in thy love, and gather it together in its holiness from the four winds to thy kingdom which thou hast prepared for it. For thine is the power and the glory for ever. 6 Let grace come and let this world pass away. Hosannah to the God of David. If any man be holy, let him come! if any man be not, let him repent: Maran atha, Amen."
7 But suffer the prophets to hold Eucharist as they will.
Nothing in the “sacrifce of the mass” is even hinted at in the prayers…just an observation.