The Didache is not a Treatise on the Sacraments. I have the William A. Jurgens "The Faith of the Early Fathers." In regards the question of the Eucharist, he footnotes an explanation for ""On the Lord's Day of the Lord gather together, break bread and give thanks after confessing your transgreessions so that your sacrifice may be pure."
Jurgens notes the Greek word used for "give thanks" could also be translated "celebrate the Eucharist." My Douai Rheims notes throughtout the New Testament that "breaking bread" was shorthand for celebrate the Eucharist.
Jurgens' collection is rife with references to the real presence from the get go and my "A Catholic Commentary of Holy Scripture" by Dom Orchard (great source for Catholics. Check online for old/used books. Mine is a 1952 edition I located in Australia) footnotes many N.T. references.
There is no doubt the NT Christians believed in the Real Presence. However, they were not sitting around discussing whether or not to adopt "transubstantiation" as the word that best describes what occurs whne they gathered to break bread.
What is interesting about the Didache - written about 140 A.D. is that it illustrates such supposeddly "inventions" as Mass, Eucharist, Confession, Baptism, Fasting (2 days a week, btw)Apostles, Bishops, Deacons...
And, for those of us living through these evil days, the Didache also notes "You shall not seduce boys."