I Wonder What Jews Do To Make Food Kosher when a Rabbi is not present.
if Meat Needs To Be Certified By A Rabbi, and one is not present at time of slaughter, Who Certifies It If Not A Rabbi Or Priest.
If the person slaughtering the meat is a God-fearing individual, then the rabbi need not be present the whole time. It is permitted for the certifying rabbi to rely on people he feels and worthy of his trust.
Note that the kashrut or otherwise of food does not depend on the certification, but rather on the actual nature of the food. Many foods are kosher even though they are not certified; some, unfortunately, have been found to be not kosher even though they were certified, because of various fraudulent and unscrupulous people. For meat, there are many sensitive matters to ensure, and it is therefore important that an officiator rabbi make a round of the slaughter-house, checking the knives, inspecting the salting process, and so on.