Any individual serving as a vintner member and his or her alternate member shall be a vintner, or a management-level employee or representative of a vintner, who has a financial interest in producing winegrapes for market. The qualifications of vintner members and alternate members shall be maintained during the entire term of office. No more than one member and his or her alternate member shall be employed by, represent, or be connected in a proprietary capacity with the same vintner. However, vintner membership in an agricultural nonprofit cooperative association or trade organization shall not be considered employment or being in a proprietary capacity.