Related for Chullin 193:8

An olive-worth of meat that falls into a pot of boiling milk: let a non-Jew taste the dish. If he says that there is a taste of meat in it, it is forbidden. If not, it [the milk] is permitted, even in less than sixty, and that piece [the meat] is forbidden. When is this true? When one quickly removes the piece before it exudes the milk that it absorbed, meaning before the pot rests from its boiling. But if he didn't remove it before it was able to exude the milk it absorbed, even if a non Jew tastes it and it has no taste at all, (Rama) it's forbidden unless there is sixty. See chapter 98 (Shulchan Arukh, Yoreh De'ah 98) that we aren't accustomed to rely on the tasting of a non-Jew and we need sixty every time.

A non-permissible [food item] that was mixed with a permissible item that is not of its type, for example prohibited fat that was mixed with meat, a non-Jew should taste it, if [the non-Jew] says that it has no fat taste or if he says that it has taste but the taste is "pagum" (somehow not good), permitted. And this is that it is not for the ends of improving. And it must be that [the non-Jew] doesn't know that he is being depended upon. And if there is not there a non-Jew to taste it, we measure it against 60. And likewise, if it is a [mixture of two things which are] of the same type, because one cannot really upon taste, it is measured against 60. {REMA: It is not done now to trust a non-Jew, and we measure against 60.}