The Hill of Soaring Birds & the Digestive System

The story of Sakai Winery begins in 1892 — the twenty-fifth year of the Meiji era — when Yasoh Sakai, the founder, planted grapevines on a steep slope in Akayu, Nanyo City, Yamagata Prefecture. The slope was so precipitous that it acquired a name: Toriagezaka — "the hill of the soaring birds," a place so vertical that only birds could ascend it with ease. Yasoh was not a trained vigneron; he was a farmer with vision, a man who believed that the volcanic soils, the abundant sunshine, and the dramatic temperature fluctuations of Yamagata's interior could produce grapes of a quality that had never been attempted in Japan. The Meiji era was a time of radical modernisation — of railroads and telegraphs, of Western dress and Western learning, of the wholesale importation of technologies and ideas that had been unknown in the isolation of the Tokugawa shogunate. Wine, in this context, was not merely a beverage; it was a symbol of civilisation, of progress, of Japan's determination to stand alongside the nations of Europe as an equal. Yasoh Sakai planted his vines in this spirit — not to replicate Bordeaux or Burgundy, but to create something that was authentically Japanese, rooted in Yamagata soil, and expressive of a new nation's ambition.

The early decades were difficult. The vines struggled on the steep slopes, the winters were brutal, the summers humid, and the knowledge of viticulture and winemaking in Japan was rudimentary at best. Yasoh and his successors — the second, third, and fourth generations of the Sakai family — learned by trial and error, by observation, by the slow accumulation of experience that is the only true teacher in agriculture. They planted varieties that could survive Yamagata's climate: Delaware, Niagara, Muscat Bailey A, and others that have since become synonymous with Japanese viticulture. They developed techniques for training vines on steep slopes, for protecting them from winter kill, for managing the humidity that encourages fungal disease. And they made wine — not always good wine, not always consistent wine, but wine that was honest, that expressed the place and the season and the hands that made it. The winery survived the Taisho era, the militarisation of the 1930s, the devastation of the Second World War, and the American occupation — a continuity of family effort that is rare in Japanese agriculture, where farms are more often abandoned than inherited.

The turning point came with Ippei Sakai, the fifth generation, who took over the winery in 2004 (or 2012, depending on the source) after studying viticulture and enology at the Tokyo University of Agriculture. Ippei brought to the family business not merely formal training — though that was essential — but a new philosophical framework that transformed Sakai Winery from a traditional producer into one of Japan's most distinctive natural wine estates. He had studied the conventional techniques of modern winemaking: temperature-controlled fermentation, selected yeast strains, filtration, fining, and the full arsenal of chemical additives that industrial wine production depends upon. And he had rejected them — not out of ignorance or romanticism, but out of a deep conviction, rooted in his family's 130-year history, that the best wines are those that require the least manipulation, that the vigneron's role is to guide rather than to control, and that the vineyard itself — its soil, its climate, its microbial life — is the true author of the wine. This was not a departure from the Sakai tradition but a return to its origins: Yasoh Sakai, in 1892, had no access to selected yeasts, no filtration equipment, no chemical additives. He made wine as the grapes and the wild yeasts made it — and Ippei, 130 years later, returned to this foundational practice with the knowledge and intentionality that only formal training can provide.

Ippei's innovations were both philosophical and technical. He introduced the concept of "forest-garden cultivation" — a polycultural approach that treats the vineyard not as a monoculture of vines but as an ecosystem in which fruit trees, native plants, and beneficial insects coexist with the grapes, creating a self-regulating environment that reduces the need for chemical intervention. He implemented "mixed varietal planting" — the interplanting of multiple grape varieties in the same vineyard blocks, a practice that increases biodiversity, reduces pest pressure, and creates complex, multi-varietal wines that express the vineyard as a whole rather than a single variety in isolation. He adopted the "Mazekoze" blending philosophy — a Japanese term meaning "mixed" or "mingled" — that treats wine as a living digestive system, blending multiple varieties and even multiple vintages to create wines of depth, complexity, and evolutionary potential that no single variety or vintage could achieve alone. And he formalised the winery's long-standing practice of unfiltered winemaking — since 1892, Sakai wines have never been filtered — into a conscious, deliberate philosophy of minimal intervention that has become the hallmark of the estate. The result is a winery that is simultaneously one of Japan's oldest and one of its most innovative — a 130-year-old natural wine estate that predates the natural wine movement by a century.

At Sakai Winery, the winemaking philosophy is expressed in a single Japanese word: Mazekoze — "mixed" or "mingled." This is not merely a blending technique; it is a comprehensive worldview that governs every stage of production, from the vineyard to the bottle, and that treats wine not as a static product but as a living, evolving organism with its own metabolism, its own rhythms, and its own capacity for transformation. The Mazekoze philosophy has three dimensions: the mixing of grape varieties in the vineyard, the mixing of varieties and vintages in the cellar, and the mixing of lees and wine in the ageing process. Each dimension reflects Ippei Sakai's conviction that complexity, depth, and evolutionary potential emerge not from the purity of a single variety or vintage but from the interaction of multiple elements — the conversation between different grapes, different years, different stages of development that creates a wine greater than the sum of its parts.

The first dimension — mixed varietal planting in the vineyard — has already been described: the interplanting of multiple grape varieties in the same blocks, creating a polycultural ecosystem that produces grapes of complementary characteristics. The second dimension — mixed blending in the cellar — extends this philosophy to the winemaking process itself. Ippei does not produce single-varietal wines in the conventional sense; instead, he blends multiple varieties — sometimes five, six, or more — to create wines that express the vineyard as a whole rather than a single grape in isolation. And he goes further, blending multiple vintages — wines from different years — to create what he calls "perpetual cuvées," wines that carry the memory of past harvests and the potential of future ones in a single bottle. This practice, common in the production of Sherry and some Champagnes but rare in still wine, creates wines of extraordinary depth and complexity: the older vintages contribute maturity, nuance, and savoury depth; the younger vintages contribute freshness, fruit, and vitality; and the interaction between them produces flavours and textures that neither could achieve alone. The Mazekoze blend is not a recipe; it is a living composition, adjusted each year according to the characteristics of the harvest, the evolution of the ageing wines, and Ippei's intuitive understanding of what the vineyard is expressing in a given season.

The third dimension — the lees ageing system — is the most distinctive and the most technically innovative aspect of Sakai Winery's production. Ippei has developed a unique method that he describes as treating wine "like a digestive system": the lees (the sediment of dead yeast cells, grape solids, and other particles that settle during fermentation and ageing) are collected not as waste but as a resource, and are aged separately in large 1.8-litre isshobin bottles — the traditional Japanese sake bottle — before being blended back into the wine. The lees, in these bottles, continue to evolve: the yeast cells autolyse (break down), releasing amino acids, peptides, and other compounds that contribute to the wine's body, texture, and umami depth. The isshobin bottles, with their narrow necks and thick glass, provide a stable, low-oxygen environment that encourages slow, controlled evolution rather than rapid oxidation. And when the aged lees are blended back into the wine — sometimes years later — they contribute a complexity, a richness, and a savoury depth that is the signature of the Mazekoze style. This is not merely sur lie ageing; it is a form of lees management that is unique to Sakai Winery, developed through years of experimentation and refined by Ippei's understanding of the microbiology of fermentation.

The unfiltered winemaking that has characterised Sakai Winery since 1892 is the technical foundation of the Mazekoze philosophy. Filtration, in conventional winemaking, is used to remove yeast, bacteria, and suspended solids that might cause cloudiness, off-flavours, or refermentation in the bottle. But filtration also removes flavour compounds, texture, and the living microorganisms that contribute to a wine's complexity and evolution. By choosing not to filter — a decision made not by Ippei but by Yasoh Sakai in 1892, and maintained by every generation since — the Sakai family has preserved the full vitality and raw expression of their grapes. The wines that emerge from this process are profoundly alive: they change in the bottle, they express vintage variation with transparency, and they carry the microbiome of Toriagezaka in every glass. The minimal sulfur that Ippei uses — the single additive that he permits himself, and then only in quantities sufficient to preserve natural flavour while maintaining stability — is not a mask for flaws or a steriliser of wine into submission; it is a gentle safeguard, a whispered reminder to the wine to remain true to itself. For some cuvées, even this minimal sulfur is omitted entirely, producing wines of extraordinary purity and vitality that demand careful handling and attentive drinking.

The wild yeast fermentation that guides all Sakai wines is not a rejection of science but an affirmation of place. The yeasts that ferment the grapes are the same yeasts that live on the skins, in the vineyard air, and on the surfaces of the century-old cellar — microorganisms that have evolved in symbiosis with the Toriagezaka environment, adapted to the steep slopes, the volcanic soils, and the dramatic temperature fluctuations of Yamagata's continental climate. These wild yeasts are not merely fermentative agents; they are terroir markers, carrying the fingerprint of the vineyard in every fermentation. Because wild yeast ferments more slowly and less predictably than selected strains, the process requires meticulous attention: daily tasting, temperature monitoring, and the patience to allow each tank to develop at its own pace. Some fermentations are fast and vigorous, others slow and contemplative; each is allowed to find its own rhythm, its own equilibrium, its own expression of the vintage and the varieties. This is not the industrial model of winemaking; it is an older, more attentive practice, a relationship between vigneron and wine that is built on patience, observation, and trust — the same relationship that Yasoh Sakai established in 1892 and that Ippei Sakai continues to cultivate 130 years later.

To understand Sakai Winery, one must understand the weight of 130 years — not as a burden or a constraint, but as a foundation, a resource, and a responsibility. The winery was founded in 1892, in the twenty-fifth year of the Meiji era, when Japan was emerging from centuries of isolation and embracing the modern world with a fervour that transformed every aspect of society. Yasoh Sakai planted his vines in this moment of radical change, not to preserve the past but to create the future — a future in which Japan could produce wine as good as any in Europe, wine that expressed the unique character of Yamagata's volcanic soils and continental climate, wine that was not an imitation but an original. The four generations that followed — each building on the work of the previous, each adapting to the changing conditions of Japanese agriculture, each preserving the unfiltered, wild-yeast tradition that Yasoh established — created a continuity of practice that is rare in any field, and almost unheard of in the volatile world of wine.

Ippei Sakai, the fifth generation, inherited this legacy not as a museum piece but as a living tradition — a set of practices, values, and relationships that he was free to adapt, refine, and extend according to his own understanding and the changing conditions of the twenty-first century. His formal training at the Tokyo University of Agriculture gave him the scientific vocabulary and technical skills to articulate what his ancestors had done by intuition and experience; his exposure to the international natural wine movement gave him a community of like-minded producers and a market of discerning consumers who valued the very practices — unfiltered, wild yeast, minimal sulfur — that the Sakai family had maintained for 130 years. The Birdup Wine brand, launched under his leadership, was not a departure from the family tradition but a crystallisation of it: a name that honoured the vineyard's history, a philosophy that expressed the family's values, and a quality that earned the winery 5-star recognition in the Japan Winery Awards every year from 2018 to 2023 — a streak of excellence that is unprecedented in the competitive world of Japanese wine.

The 5-star Japan Winery Award is not merely a commercial accolade; it is a recognition of excellence that is assessed by blind tasting, technical evaluation, and peer review — a standard of quality that is as rigorous as any in the international wine world. To achieve it once is an honour; to achieve it six consecutive years is a testament to consistency, dedication, and the kind of deep, place-based quality that cannot be manufactured or marketed into existence. The award recognises not merely the taste of the wine but the integrity of the production: the health of the vineyard, the sustainability of the farming, the skill of the winemaking, and the transparency of the philosophy. Sakai Winery's 5-star streak is a validation of everything that Ippei and his ancestors have built: the sheep-grazed steep slopes, the forest-garden cultivation, the mixed varietal planting, the Mazekoze blending, the isshobin lees system, the unfiltered tradition, and the wild yeast fermentation that has been the hallmark of the estate since 1892. It is proof that natural wine, made with patience and integrity, can achieve the highest standards of quality — not despite its minimal intervention but because of it.

The future of Sakai Winery is tied to the continuation of this legacy — not as a static preservation of the past but as a dynamic evolution that honours the founders while adapting to the challenges of the present. Climate change is altering the growing conditions in Yamagata: warmer winters, more intense summer heat, unpredictable rainfall patterns, and the increasing frequency of extreme weather events that threaten the delicate balance of the vineyard ecosystem. Ippei responds not with chemical interventions or technological fixes but with the same polycultural, biodiversity-based approach that has guided the estate for 130 years: planting more heat-tolerant varieties, adjusting canopy management to provide more shade, improving soil organic matter to increase water-holding capacity, and maintaining the genetic diversity of the vineyard that is its best insurance against catastrophic loss. The sheep continue to graze, the fruit trees continue to bloom, the wild yeasts continue to ferment, and the isshobin bottles continue to age their lees — a living system that adapts and evolves, that learns and remembers, that is not merely surviving but flourishing.

In an age of industrial wine production, of homogenised flavours and marketing-driven branding, Sakai Winery stands as a radical alternative — not because it rejects modernity but because it has integrated modern knowledge into a tradition that predates the modern era. The unfiltered wines, the wild yeast fermentations, the sheep-grazed slopes, the mixed varietal plantings, the Mazekoze blends, and the isshobin lees system are not innovations of the natural wine movement; they are practices that the Sakai family has maintained for 130 years, refined by each generation, and articulated with new precision by Ippei's formal training and international exposure. This is not a winery that has adopted natural wine as a trend; it is a winery that invented natural wine before the term existed, that has proven its viability across five generations, and that continues to demonstrate that the best wines are those that express the true character of their place, their time, and the hands that guide them. The hill of soaring birds, the digestive system of lees, the 5-star legacy, and the 130-year tradition: these are not merely features of Sakai Winery; they are the expression of a family, a place, and a philosophy that has endured, evolved, and excelled — and that points the way toward a future in which wine is not merely a product but a living, evolving, deeply human art.