"Rabbi Gavriel Price is in charge of figuring out how . . . the largest kosher certifying organization in the world, should deal with meat that is grown in laboratories from animal cells"

NYT:

This brings him in touch with a possibility for Jewish cuisine that had previously seemed impossible: kosher bacon.

...

When Rabbi Price visited the Mission Barns labs, he asked questions specific to kosher certification. He wanted to be sure, for instance, that the pork cells growing in one incubator never come into contact with the duck cells in the incubator next to it, and that the centrifuge where the meat cells are processed is cleaned thoroughly between processing.

He also wanted to know if the cells in the flasks changed as they replicated, to be sure that they do not morph into something that no longer resembles the original animal cells.

...

The liveliest conversation grew out of research that is looking into whether clean meat might be derived from cells in animal saliva or hair.

The rabbi said those substances are not meat