LC chromatograms of ginger related commercial products: (A) selected ground ginger powder, ginger tea leaf, and crystal ginger drink; (B) three crystal ginger drink samples (Sample #1, #2, and #3); (C) five ginger tea leaf samples (Sample #4, #5, #6, #7, and #8); (D) three ground ginger powder samples (Sample #9, #10, and #11).