Commercial horseradish typically uses “field roots” or “stringers”. Bails of stringers are washed and loaded onto a conveyor to be fed into the “mashing” unit which crushes the horseradish into a fine paste that is then set in vinegar, water and salt. All imperfections are ground in with the root (and believe me, there are some serious imperfections). Only the white fleshy part of the root is activated in the grinding process so much of the commercial horseradish consist of elements of the root that do not produce heat.
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