Bob Flexner has had several articles in Popular Woodworking over the years. He concludes that nearly all finishes are food-safe once fully cured.  I haven't cross-checked his conclusions against other opinion or research.  See https://www.popularwoodworking.com/article/the_many_faces_of_varnish/2/  (2007); https://www.popularwoodworking.com/techniques/q-a-is-polyurethane-food-safe/ (American WW, 2002);  https://www.popularwoodworking.com/nov16/explaining-polymerized-oil/   (2016)   You can also, for $1.99, download his Nov. 1999 Pop WW article "The Folly of Food-Safe Finishes"   https://www.popularwoodworking.com/product/flexner-on-finishing-the-folly-of-food-safe-finishes/.          Out of curiosity, I just did a simple search at the Fine WW web site, without logging in.  Go to https://www.finewoodworking.com/, enter "food safe finish" in the search window, and you'll see a number of articles, beginning with this January's https://www.finewoodworking.com/2019/01/10/food-safe-finish-considerations.  If you turn up anything helpful and authoritative, please let me know!