Georg's reaction is very appropriate.
Too often we hear: "Scientists have said that..." followed by something totally unscientific and often totally false.
Even if scientists have said something it does not have to be true, correct, or even meaningful. Even if a non-scientist has said something it does not have to be untrue, incorrect, or even meaningless.
In this case, the very nature of the statement is unscientific. Possibly the "scientist" was a pharmacologist or botanist rather than a cosmologist or even a physicist. Or he might have been on holiday. Whatever he was, he was not talking science or sense if the source of your quote was at all accurate.
We have no foreseeable way, either of testing, much less confirming the assertion. It is not at all clear that the big bang needed to conserve matter or energy; such conservation might be a property with in this universe only for all we know. No one has yet returned from elsewhere with good evidence for what obtained outside our universe. Maybe even in this universe matter/energy is not conserved; remember that only about a century ago people thought that matter was conserved and energy was conserved.
How silly of them! Any fool should be able to tell that matter and energy can interconvert!
Or should he?
Look, the day may come when we recognise some undebatable source of evidence for what happened where we look beyond the big bang (note that I do not say "before" because it is not even certain that there was a "before" in any meaningful sense. Even my use of the term "beyond" is no better than a confession that I can recognise no better word at my disposal.)
For all we know at present there may not have been anything leading to the big bang; not even any space, not even any virtual particles, certainly not even energy. The very concept of energy might be limited to what we see about us. In those days, still for all we know, a statistical fluke might simply have torn a quantum of negative energy into existence, thereby creating a quantum of positive energy, much as when a certain person said: "Let there be light!" He left a shadow that has been plaguing us ever since.
Possibly before there was a big bang the only thing that existed was the law of unintended consequences. I don't know; as far as I can tell I am just one of the unintended consequences. Anyway, that rip in unreality might have extended and still be extending, creating expanding space as it goes.
So when that hypothetical scientist next suggests to you that our continuing big bang all began with energy, ask him why it should have began with anything at all; what did the energy begin with, never mind where?
There is more to being a scientist than science. It also takes behaving in a scientific manner, in certain contexts at least. Who ever told you that story about the energy might have been right or might have been wrong, but as it stood the statement was not scientific.
