Q: If someone gets a job working as a chef can they cook meat and milk
together if its not being eaten by the person, only others and assuming
that the others aren't Jewish.
A: It is prohibited to cook meat and milk even if the resulting product
will not be consumed at all, as in an analytical lab test, or if it will
only used for animal feed. (Yalkut Yosef 3 pg.197). Our tradition is to
prohibit cooking non-kosher nevaila meat (that did not undergo proper
shechita), However, this does not apply to meat from a non-kosher
species. (see Shulchan Aruch YD 8,3 and 4 – Taz and Shach ibid.)
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit"a