The use of the materials names (not food, that was merely a nonsequitur) varied in date from place to place, but isn’t known to be used that early.
And yet not only were they working with stone but they were working with big stones.
They thought that metal was first worked in the middle east around 4200 BC. They they found Varna. And found worked metal from 4600 BC and in Europe.
And now they found a copper chisel that is from 5500BC in Prokuplje Serbia.
The more we find the more the dates keep getting pushed back.
Saying "before we know metal was used" is correct. Saying "before metal was used" is not.