Ito En removed oxygen from canned green tea and created the unsweetened tea market

Green tea is Japan's drink and its packaging nightmare: minutes after brewing, oxidation dulls the color and flavor. That is why, until the 1980s, unsweetened green tea existed only in the teapot. Ito En, a tea-leaf wholesaler turned drink maker, had already canned oolong tea in 1981; in 1985 its deoxygenation technology solved green tea itself, and the world's first canned green tea went on sale — with no fragrance, flavoring or preservatives added. The unsweetened-tea market in Japan exists because that filling process exists.

The Porter Prize jury's analysis describes an unusually integrated chain. Flagship Oi Ocha declares 100% domestic leaves — Ito En uses about a quarter of Japan's raw-tea harvest, giving it scale power in sourcing, backed since 2001 by a program sharing mechanization know-how with farmers. Firing and blending happen at its Sagara plant; extraction and bottling go to competing packers, so Ito En flexes volume with demand, uses each packer's best line, and captures their innovations, like the chemical-free NS filling system and ultra-thin PET bottles.

Distribution is the third leg. While rivals outspent it on advertising, Ito En kept about 4,000 route-sales employees — all salaried, out of 5,307 staff across 201 bases — who propose shelf-by-shelf assortments: small containers for a park kiosk, hot-drink cases placed away from the drink aisle, tailored lineups for offices, temples, hospitals. The company even certifies its own tea tasters; 1,460 employees held certification as of May 2013.

Even the waste became product. Brewing 46% of Japan's bottled tea leaves about 49,000 tons of spent leaves a year — roughly a month of trash for the city of Nagoya — so since 2001 a recycling system with paper maker Rengo has turned tea residue into paper, board, resin and building materials without drying it. By 2024 the residue fed more than 100 products, including a golf-club grip co-developed with Yonex, and in 2025 a tea-residue dye for Pilot leather goods.

Remove the oxygen, and a national drink becomes a product

Deoxygenation filling removed the single objection — oxidation — that made unsweetened green tea unsellable in a sealed container.

Outsourcing bottling to competing packers gave capacity flexibility and a stream of process innovation without capital expense.

A quarter-share of national leaf procurement anchored both quality and cost, and the farming program protects that supply.

A salaried route-sales force customizes every shelf, easing price competition where drinks are discounted hardest.

Recycling the spent tea turns a disposal liability into materials, goods and a visible environmental credential.

A category is born the moment its biggest physical objection dies. Kill it with process technology, then wire the whole chain — sourcing, production, selling, waste — so rivals must copy the system.

Unsweetened tea became Japan's default packaged drink, and Ito En's green-tea line stayed the category's core even as the domestic market peaked around 2005. The Porter Prize recognized the company's whole-chain strategy in 2013. The tea-residue business kept compounding: more than 100 residue-based products by late 2024, including the Yonex golf grip, and a tea-dyed leather series with Pilot launched in June 2025, both reported by Nikkei.