Cockroach milk is sourced from the Pacific Beetle cockroach, a type of roach that gives birth to live offspring and produces ‘milk’, which it feeds its embryos through a ‘brood sac’ (essentially a cockroach womb). There is, in fact, no actual ‘milking’ involved: scientists need to carve out the cockroach’s gut in order to access the milk, which is in the form of crystals.