Maidenstoen: Another New Benchmark in California Dry Riesling

Raised at Danville, in the San Ramon Valley east of San Francisco, Mike Callahan grew up a self-described snowboarder. Once he had finished high school, he headed directly to the powder-covered slopes around Steamboat Springs.   When his parents persuaded him to try college, he moved to Boulder, where he began working outside of class hours at a local beer, wine and liquor store. Those unfamiliar with Colorado are often surprised to learn that its wine market is unexpectedly sophisticated, with imported wines accounting for almost half of total sales. Callahan reports that the store’s owner “brought him from beer keg to wine cellar,” changing fundamentally his ideas about life and career.


If wine over beer was Callahan’s first epiphany, wine’s geographic diversity was the second. Conveniently, his father worked for airlines and took his family to Europe, where the multifarious geography of wine “blew [his son’s] mind.” In 2003, Mike Callahan returned to California, married a young woman with roots in Los Angeles, and looked for jobs at wineries in Santa Barbara County. He worked mostly tasting room jobs at first, then moved on to assignments in cellars and a harvest at Orcutt Road Cellars, a large state-of-the-art production facility in Edna Valley. In 2005, he spent most of the year with Ken Volk, a legendary wine pioneer on the Central Coast, following the latter’s purchase of the old Byron winery.   Eight vintages at Testarossa Winery in Los Gatos followed, where Callahan worked as assistant winemaker to Bill Brosseau, who had built the Testarossa Brand for founder Rob Jensen. This time was formative. Callahan learned to read vineyards, adjust winemaking to their individual personae, and grew facile with technical wine analysis.


By 2012 Callahan had developed a personal set of “quality metrics” for the kind of wine he liked, which included low pH, moderate to high acids, clean juice, and “microbial stability,” all in the service of flavor and age-ability. These metrics led him to white wines created without skin maceration. As it happened, one of Testarossa’s many sources for pinot noir and chardonnay was Luis Zabala’s vineyard in Arroyo Seco, and Zabala also grew Riesling. Rather a lot of Riesling actually; Zabala had planted just under 20 hectares of FPS 12 (~N90, from Neustadt) in 2007. Callahan liked the looks of Zabala’s vineyard: water-washed stones everywhere, plus scattered rocky outcroppings. He also knew that Riesling developed lots of flavor early in the ripening process, and retained acid well in the last weeks before harvest, making it score high against his personal set of quality metrics. Plus Riesling was an out-of-favor variety, and Callahan had always “rooted for underdogs,” in sports and in life. So he cast the dice, launching Maidenstoen, his own label, devoted entirely to Riesling and to single-vineyard wines, which he made at Micah Cellars in Watsonville, conveniently located between Zabala’s vineyard and his day job at Testarossa.


Maidenstoen’s winemaking protocol was (and generally remains) straightforward. To choose a pick date, Callahan assesses physiological ripeness, looking for good flavor before the pH rises above 3.2, and while acid is still abundant. The fruit is pressed as whole clusters, and settled without additives for 24 hours before being racked to fermentors, which are a combination of stainless steel drums and well-used French barrels. The yeast of choice is QA23, isolated by the Universidade de Tras-os-Montes e Alto Douro in Portugal, which is widely used across the New World for sauvignon blanc and other aromatic varieties. It is also known to work quickly and completely even at relatively low temperatures (between 12 and 16° C), leaving very little unfermented sugar. Once dry each new vineyard-specific wine is racked from the drums and barrels in which it was fermented to a new array of drums and barrels where it remains for nine months’ élevage. At this point each component of each wine is evaluated before a final blend of each wine is made, sterile filtered and bottled. No fining has been necessary for any of the fourteen wines produced through the 2016 vintage.


Callahan’s 2012 from Zabala was not released commercially; Maidenstoen debuted the following year. There were two wines that year: one from Zabala and one from a high-elevation vineyard a few miles northeast of Zabala called Coast View.   Both were dry, taut, linear and delicious. (See below for tasting notes.) In 2014, Callahan added a third vineyard to his portfolio, Lafond on Santa Rosa Road in the Sta. Rita Hills appellation. Lafond made a slightly rounder and fruitier Riesling than either of the Salinas Valley sites, but was still taut and dry. In 2015 Tondré’s Grapefield in the Santa Lucia Highlands was added to the list of source vineyards, in part to offset the parsimonious yield that year from Coast View, whose high elevation makes it vulnerable to wind and rain from the Pacific. In 2016 Callahan replaced Tondré with fruit from Oliver’s Vineyard in the Edna Valley, fastidiously farmed by Brian Talley. He also changed the style of the wine from Zabala, leaving it with 11.8 g/L of residual sugar, but maintaining the bone-dry style for all of the other wines.


Meanwhile, in the spring of 2014, Callahan had changed day jobs, moving from Testarossa to Chamisal Vineyards in Edna Valley. Maidenstoen moved with him of course, but the transition turned out bumpy logistically, requiring two unexpected relocations and a good deal of lost sleep. In 2017 he remarried, purchasing property with his new bride on enough acreage that both an on-site winery and vines became imaginable. Sorting these changes and opportunities, Callahan shrank the Maidenstoen portfolio in 2017 to a single wine – from Lafond – and will redefine it for 2018 to rely on a compact array of Central Coast vineyards.  He has also taken budwood from several California vineyards to create plant material for a three-acre all-Riesling estate vineyard a short distance from Avila Beach.  Meanwhile, the 2015s and 2016s  have shown well in several high-profile trade tastings, scored well in the Wine Enthusiast, and found their way to the shelves of a few enlightened wine shops in California, Tennessee and Colorado.   And the brand remains devoted entirely to Riesling and (with the aforementioned single exception) to Riesling’s dry persona.  All of which augers well for the future of Maidenstoen.


Tasting Notes.


Arroyo Seco Riesling Zabala Vineyard 2013

Lean, tightly-wound attack; on the palate, dried herbs and macerated flowers against a crescendo of minerality; citrus and top notes of white-fleshed melon at mid-palate; dry with great tension and considerable length. Excellent and age worthy.


Arroyo Seco Riesling Zabala Vineyard 2016

Sweet pear, apple and citrus attack; then savory at mid-palate. With 11.8 g/L of residual sugar and 9.5 g/L of acid, and pH just a hair under 3.0, the wine is dry-ish, attractive and friendly, but lacks the cut, edge and tension of earlier vintages, all of which were much lower in residual sugar. Callahan made the style change very deliberately, worrying that Zabala’s typicially high acidity, atypically high in 2016 even when some of the grapes were picked atypically late, risked making a wine that would have been “sour” and “too challenging” if all lots had been permitted to go fully dry.


Monterey County Riesling Coast View Vineyard 2016

Slightly closed aromatically, but generous on the palate, with melon, citrus and resinous herbs (especially bay laurel). Very dry, linear and taut; built to age felicitously, but already delicious in the spring of 2018. In 2016 this bottling replaced the slightly off-dry Zabala as my personal favorite among the Maidenstoen Rieslings. Alas, however, this will be the last Riesling from Coast View; facing unpredictable and sometimes derisory yields, the vineyard’s owner has now re-budded his Riesling vines to another variety.


Edna Valley Riesling Oliver’s Vineyard 2016

Broad-shouldered, muscular and fruit-driven wine, showing orange and tangerine peel on the attack, then stone fruits and cantaloupe. Almost lush but still tightly-wrapped at mid-palate, higher pH and lower acid than either Zabala or Coast View, this wine lacks their tension, but is still delicious.