De Eucharistae

Even what we have come to call 'the words of institution' are absent from some early Eucharistic settings.

Sr Patricia Smith RSM, Teaching Sacraments

The short answer to Tyson's question, "is this true?" appears to be no.

Long post re: your question this morning.

So, from what I can see, " Ambrose says (De Sacram. iv): "The consecration is accomplished by the words and expressions of the Lord Jesus. [...] the form of this sacrament implies merely the consecration of the matter, which consists in transubstantiation, as when it is said, "This is My body," or, "This is the chalice of My blood." " (ST IV q78 a1)
Not 'Words of Consecration;' no Consecration.

As for the old Liturgies not having that:
Liturgy of St Mark:

"The Priest (aloud): For this is my body, which is broken for you, and divided for the remission of sins.
The People: Amen.
[...]
The Priest (aloud): For this is my blood of the new testament which is shed for you and for many, and distributed among you for the remission of sins.
The People: Amen."

Liturgy of St James:

"Then he says aloud:— Take, eat: this is my body, broken for you, and given for remission of sins.
The People: Amen.
Then he takes the cup, and says:— In like manner, after supper, He took the cup, and having mixed wine and water, lifting up His eyes to heaven, and presenting it to You, His God and Father, He gave thanks, and hollowed and blessed it, and filled it with the Holy Spirit, and gave it to us His disciples, saying, Drink all of it; this is my blood of the new testament shed for you and many, and distributed for the remission of sins.
The People: Amen."

Also, from the Apostolic Constitutions, Book VIII

"Being mindful, therefore, of those things that He endured for our sakes, we give You thanks, O God Almighty, not in such a manner as we ought, but as we are able, and fulfil His constitution: For in the same night that He was betrayed, He took bread (1 Corinthians 11:23) in His holy and undefiled hands, and, looking up to You His God and Father, He broke it, and gave it to His disciples, saying, This is the mystery of the new covenant: take of it, and eat. This is my body, which is broken for many, for the remission of sins. In like manner also He took the cup, and mixed it of wine and water, and sanctified it, and delivered it to them, saying: Drink all of this; for this is my blood which is shed for many, for the remission of sins: do this in remembrance of me. For as often as you eat this bread and drink this cup, you do show forth my death until I come. "

The only thing I can think of is that perhaps Sister means that it wasn't mentioned in St John's Gospel?

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http://www.newadvent.org/fathers/0718.htm
http://www.newadvent.org/fathers/0717.htm
http://www.newadvent.org/fathers/07158.htm
http://www.newadvent.org/summa/4078.htm#article1