Some food extension articles say 'never use', but several say "Full rolling boil for one minute' See Clemson University Food Extension.
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https://www.google.com/search?q=food+extension+marinade+reuse&rls=com.microsoft:en-us:IE-SearchBox&ie=UTF-8&oe=UTF-8&sourceid=ie7&rlz=1I7GGLL_en