with extra care and effort, mizawa has made it suitable for fine wine. >> translator: i was born into a family that really treasures koshu grapes. i grew up with them. for other winemakers, it's just another variety, one of many species of grape. but for me, it's truly precious. >> reporter: she studied authentic winemaking at bordeaux university in france. there she learned the methods of cultivation that are needed to make a bottle of fine wine. >> translator: i learned that winemaking techniques in japan are not as refined. in japan the focus is on the winery, but in france it's on the vineyard. >> reporter: after she returned to japan, she was determined to change the method of growing koshu grapes. she planted the crops in a completely different way, with the shrines growing vertically. this gave them a higher sugar content, which is key to making good wine. she then selected the sweetest grapes by hand and only used those for cultivation. after laboring for five years, her efforts paid off. she grew a crop of the sweetest grapes yet. the grapes won a gold prize last year at one