Kosher Certification as we know it is a truly modern phenomenon. The core of Kosher requirements is obviously biblical in nature. There are, however, many Rabbinic requirements as well, many of which were instituted as the first Food Safety program, as a precaution against inadvertently eating non-Kosher food, and to ensure that no nonKosher ingredients or equipment was used.
One of these Rabbinic ordinances requires certain cooked foods to have been prepared by Bishul Yisroel., i.e. that a Kosher-Observant Jew take part in the cooking process.
This requirement does not apply to all cooked foods. For example, a food that could be eaten raw does not require Bishul Yisroel when it is cooked. The guidelines delineating which foods require Bishul Yisroel are complex; a company should consult their Kosher Certifying agency regarding each product.
In a commercial setting, it would be virtually impossible to have all food cooked directly by a Kosher Supervisor. However, Kosher Law states that Bishul Yisroel can be achieved if the Kosher Supervisor has made a significant contribution to the cooking process.
Most equipment in manufacturing facilities operates by heat produced by a central boiler. This will easily allow for Bishul Yisroel products once the boiler has been lit by a Kosher Supervisor, and the boiler maintains cooking temperature.
However, once the cooking device is turned off and loses its heat, the products cooked will not be Bishul Yisroel until the next time a Kosher Supervisor re-lights the cooking device. To provide for such situations, signage should be present notifying the staff to alert the Kosher Agency in case of a gas or power shutoff. Often, systems are set up by which the supervising agency can monitor and reinstate the Bishul Yisroel status, often from a remote location.
Working together, a company and its Kosher Certifier can find a Bishul Yisroel solution that will allow production to proceed seamlessly while fulfilling the highest Kosher standards.