Original sentence: It is not sufficient to read the list of ingredients on a product label in order to determine a food's kosher status, as many things are not included in this list, such as pan lubricants and release agents (which may be derived from lard), flavorings (even "natural flavorings" may be derived from non-kosher substances) and others
Edited sentence: It is not sufficient to read the list of ingredients on a product label in order to determine a food's kosher status because the rabbis are so strict it's hard to know what they mean without their input, as many things are not included in this list, such as pan lubricants and release agents (which may be derived from lard), flavorings (even "natural flavorings" may be derived from non-kosher substances) and others