Many believed the sale to Constellation of the Robert Mondavi Winery would signify the end of the Mondavi name as a wine industry leader. But as David Robertson reports, a new project is healing major rifts in California wine's first family and could return the famous name to limelight.

After a family feud that has lasted four decades the two halves of the Mondavi family are finally coming together again in what is likely to be one of the most anticipated events in the Californian wine industry this year.

Peter Mondavi Sr, who, with his sons, runs the Charles Krug Winery in the Napa Valley, and Robert Mondavi, who founded the eponymous wine brand, are making a 10 case lot that will be sold at auction in June.

The collaboration ends a family division that has existed since 1965 when Robert left Charles Krug, the winery his father bought in 1943.

Peter Mondavi Jr, son of Peter Sr and nephew of Robert, told just-drinks: "I kind of spearheaded the idea on our side and when I raised it with Dad he thought it was great. Then I went to Tim Mondavi [former vice chairman of Mondavi Corporation] and he ran it by his Dad.

"Tim and I are actually doing the groundwork on tasting all the wines and so forth, and then we'll bring Robert and my dad, Peter, to go through the subset of wines we've narrowed it down to and they will make the final choice."

"We've decided on the blend and in the next couple of weeks we'll get the barrels together and blend them. Its predominately a Cabernet but probably not enough to call it a Cabernet, so it'll be a proprietal blend. The lot is called Ancora Una Volta, which in Italian means Once Again, and this will probably be the name of the wine."

The two halves of the Mondavi family plan to auction the wine at a Napa Valley Vintners Association gathering on June 4th.

The winning bidder (and five of his or her friends) will then join Robert, Peter Sr. and the rest of the Mondavi clan for lunch at Robert Mondavi's house the next day.

Another lunch will take place at Peter Sr's Charles Krug winery six months later for further tasting. The release party is expected to be in August 2006.

Such a prize would obviously be highly valued by any wine buff and interest in the auction has been intense - something that has surprised the family.

Peter Jr. said: "There seems to be a tremendous amount of excitement about this project in the wine industry. But I guess this is the first time in 40 years that my dad and Robert have got together in wine making.

"And time is running out to get Dad and Robert together [they are both in their 90s]. They no longer have a competitive winery so the timing was appropriate for the two to get together."

However, what many in the Californian wine industry really want to know is whether this collaboration between the two halves of the famous wine-making family will be repeated - and even expanded into a commercial enterprise.

But Peter Jr. is coy about future prospects for an alliance: "It has not been ruled out, but nor has it been discussed in any depth. The next natural step is whether we continue this project on to the next year and I think we'll wait and see how the lot is received."

The Mondavi family saga has fascinated the wine industry for decades. It began in 1943 when Cesare Mondavi bought the Charles Krug Winery, the oldest winery in Napa Valley (founded 1861).

His sons Robert and Peter took over the business but fell out over strategy: Robert wanted to expand the business and make higher quality wines while Peter was happy running the winery as it was. The dispute escalated and Robert left the family firm under acrimonious circumstances.

A year later, in 1966, Robert Mondavi set up his own wine-making company, eventually building it into the sixth largest producer in the US. It was a business that is credited with helping to define Napa Valley, and California, as a world-class wine-producing region.

In 1993, Robert Mondavi's company listed on the stockmarket and, for many analysts, that's when the problems began. The conflict between a winemaker's urge to lavish attention on his product and a shareholder's desire to get as much product out as cheaply as possible tore the company apart.

This was reflected in a never-ending debate over whether the high quality "luxury brands" should be sold alongside supermarket brands like Woodbridge. The Mondavi Corporation was eventually sold to Constellation Brands in December 2004 for US$1.36bn, which effectively ended Robert's career in the wine industry.

Meanwhile, the other side of the family has continued in the slow and steady fashion that caused the original rift between Robert and Peter Sr.

Charles Krug now owns more than 800 acres in the Napa Valley and produces 70,000 cases a year of Krug-branded fine wines. Peter and his sons, Peter Jr. and Mark, also own the CK Mondavi supermarket brand, which sells about a million cases a year.

Peter Jr told just-drinks: "We are modest sized for the Napa Valley with about 70,000 cases but we're growing nicely at 8 or 9% a year.

"We've made a significant investment of about US$20m in replanting vineyards, a new barrelling operation and a new crash fermentation facility so we can focus on smaller lots. It's a lot to invest for a private company."

The sale of the Mondavi Corp to Constellation Brands does not affect Peter Jr's side of the family but there are some concerns about what Constellation might do with the family name, particularly as CK Mondavi wines might be sold next to Robert Mondavi wines on supermarket shelves.

Peter Jr explained: "Obviously Constellation has the trademark "Robert Mondavi" and it's a concern of ours what they do with it, but we just have to make sure we differentiate ourselves from those brands.

"The fact that we have had CK Mondavi out for 60 years offers a tremendous amount of protection. Constellation can't use just "Mondavi", it has to be "Robert Mondavi", so with that I think there is enough protection. If they had the ability to say "Mondavi" on its own that would be a concern."