Zinfandel under the microscope

A team in the US is conducting research into the diversity of the Zinfandel grape. The project, called the Zinfandel Heritage Vineyard, is a partnership between UC Davis and the Zinfandel Advocates and Producers, the organisation dedicated to advancing the knowledge and appreciation for American Zinfandel. James Wolpert of the University research team explained that they began their ‘Zinfandel safaris’ in the early 1990s, looking for diversity within the grape variety among the 100-plus year old vineyards in California. He told ThirtyFifty: ‘We collected about 80 selections from 40 vineyards in 16 counties.’ These were planted in over an acre in the Napa Valley. Joel Peterson from Ravenswood Wines, the biggest producer of Zinfandel in the US and a member of ZAP, told the UK Wine Show that the selections have already been narrowed down to 20 very interesting variations. Professor Wolpert said that, ‘We are in the process of making wines from the selections – after all, wines are the final arbiter of useful differences.’ But, he added, ‘We have at least three, maybe five, more vintages ahead before we feel confident enough to release a “superior” selection. This is not work for the impatient,’ he explained. And what does the project hope to achieve? Joel Peterson said, ‘It will give us the clonal knowledge to plant better Zinfandel in the future or at least match clonal variation with site in a way that’s the most constructive.’