Elsewhere the Book of Mormon text has at least ten examples of “to taste of ”, including two dealing with fruit:
There is also one more passage that has “of which” at the head of a relative clause as well as a second example of “to taste of ”:
There appears to be a partitive sense when the preposition of is used with taste.
Summary: Restore in 1 Nephi 11:7 the original preposition of at the head of the relative clause “of which thy father tasted”, especially since the partitive usage in “to taste of fruit” is the normal phraseology in the Book of Mormon.