Final answer:
The minimum grape percentage for varietal wines in California is 75%, ensuring that wines labeled as such accurately represent the grape variety stated on the label.
Step-by-step explanation:
In American wine labeling, particularly concerning California (CA) regulations, the minimum grape percentage required for a wine to be labeled as a varietal (a wine made primarily from one specified grape) is 75%. This means that at least 75% of the wine must be made from the grape variety that is named on the bottle's label.
Spanish missionaries were the pioneers in introducing viticulture to California, which now has an extensive wine industry embedded in its agricultural economy. Wine production details, such as varietal labeling requirements, are essential for maintaining the integrity of the wine market and consumer trust.