Complex sentence: Zinfandel was long considered "America's vine and wine", but when University of California, Davis (UCD) professor Austin Goheen visited Italy in 1967, he noticed how wine made from Primitivo reminded him of Zinfandel.
Split into simpler sentences: Zinfandel was long considered "America's vine and wine". But when University of California, Davis (UCD) professor Austin Goheen visited Italy in 1967, he noticed how wine made from Primitivo reminded him of Zinfandel.