The Katzman glucose matrix was glucose structural pattern used by food synthesizers in the 23rd century, among the two most common matrices along with the Gupta glucose matrix.
While trapped in a turbolift, newly assigned Ensign Spock asked Number One if the USS Enterprise used the Katzman or Gupta glucose matrix. She noted the Enterprise used the "Una glucose matrix" that she created, combining the best qualities of each with a more palatable result. (ST: "Q&A")