Napa, Calif.—Valentin-Thierion Corp. the U.S. subsidiary of the supplier based in Epernay, France, announced that general manager Gerard Rottiers will be retiring after more than 40 years in the U.S. and global wine industry. Rottiers worked his first harvest in 1970 and will be moving to the Loire Valley where he will continue to work as a consultant to the wine industry. Antoine Dupont-Calderon who was trained under Rottiers' supervision will be managing the North American company branch of the company that has been in business for 155 years. Based in Napa, Calif., Valentin-Thierion specializes in sparkling wine equipment and technology.