Duke"s tartar sauce is made with the highest quality ingredients, including pickles, olives and capers, to complement your fish or seafood dinner perfectly. It contains 2 percent of vitamin A and 2 percent of vitamin C. Duke"s is still made in Greenville, South Carolina. Mrs. Duke"s kitchen has been replaced by a modern production facility that turns out 240 jars of mayonnaise a minute, but the uniquely Southern recipe for Duke"s Mayonnaise has remained the same. "We"ve never changed the formula,” explains Mark Sauer, vice president of sales for C.F. Sauer and great-grandson of Conrad Sauer, Sr.