Jungmann, Josef A., S.J. "Chapter Four: The Breaking of Bread: The Oldest Form of Eucharistic Service." The Early Liturgy to the Time of Gregory the Great. (translated by Francis A. Brunner, C.S.S. R., Notre Dame, Indiana: University of Notre Dame Press, 1959, pp. 29-38.
Acts 2:42, 2:46, 20:7, and 1 Corinthians 10:16 make it clear that a Eucharistic celebration, the breaking of the bread, was at the center of early Christian worship. Jungmann sees this as a direct continuation of the events in the Last Supper. He also sees it as distinct from a meal, saying "nowhere is there evidence that in profane speech the expression 'breaking bread' ever meant 'having a meal' (Jungmann 1959, 29). Though it requires some speculation, from the few early accounts we can draw some conclusions about the Eucharist.
Jungmann notes that in 1 Corinthians the Eucharist was associated with a meal. Paul's exhortation to the Corinthians was not to change the meal, but to avoid abuses in the meal. A celebratory meal was a common theme in Jewish thought and made sense in the context of a messianic celebration (Jungmann 1959, 30). Because of the association of the Last Supper with Passover, most would view the Eucharist as related somehow to the Paschal meal, but with some added sacramental significance. However, Jungmann suggests it is more likely to be related to the Jewish custom of a Sabbath evening meal (Jungmann 1959, 31). The breaking of bread and praise to God was at the start of a meal, while a "cup of blessing" came near the end. The ritual, as Jungmann sees it, may have been literally surrounding a meal, as suggested by Luke and Paul who specify the cup is "after it has been eaten." It may also have been one event, without a meal in the middle, as suggested by Matthew and Mark, who make no mention of "after it has been eaten" (Jungmann 1959, 32). In the end, the meal may have been omitted, leading to the liturgy we retain to the present. Jungmann cites Dix and his analysis of the seven liturgical actions in the liturgy as an authority on early practice (Jungmann 1959, 32).
Jungmann notes that in Hippolytus' Church Order the newly baptized receives first bread, then a chalice of milk and honey, which is a traditional meal for a newborn. They then receive water, which recalls washing, then they receive the wine. This practice was still known in Rome as late as 215 (Jungmann 1959, 35). The Didache also makes statements about the practice of communion, which would be applicable to a slightly private gathering as well. The prayers are suited to a Eucharistic meal of some substance (Jungmann 1959, 36).
The words of institution bear comment. Jungmann observes that in the Gospels and in 1 Corinthians they are recorded differently. He suggests this is a reflection of differing liturgical usage in different communities. The sacrament is the same but the words which introduce it may have some variation (Jungmann 1959, 37).