Algolia/Scout - prevent operations update for certain updates

I'm using Algolia, via Laravel I'm frequently updating some entries in my database (every 5 mins), e.g. $object->update(['field'=>$new_value])

I would NOT like these changes to trigger updates / "operations" in Algolia, as this field is not relevant for Algolia's search indexing, and it would otherwise generate too many operations (which I'm then billed for).

Other changes should trigger updates in Algolia.

How can I do this?

via Chebli Mohamed