What the category is, and why a tea catalogue tends to miss it
A description of something people do now, compiled from published accounts rather than from practice.
A tea catalogue is built around leaf: what it is, where it grew, how to brew it. Bottled tea is none of those things from the drinker's side. It arrives cold, already made, in a sealed container, usually unsweetened, usually from a vending machine or a convenience-store chiller, and it is bought the way water is bought rather than the way tea is bought. That makes it easy to regard as a lesser thing — an industrial shadow of the real subject — and it is a mistake, because for an enormous number of people the bottle is not an alternative to drinking tea. It is how they drink tea. A page that describes only leaf, water and time is describing a minority of the world's actual tea consumption and does not say so.
The chronology, taken from the company that set it
Attested in the historical record, and sourced to it.
ITO EN's own corporate timeline gives the sequence, and it is worth setting out precisely because almost everything written about it secondhand is loose. The firm was established in 1966 as Frontier Tea Corporation in Shizuoka and took its present name in 1969. In 1979 it signed an agency contract with the China National Native Produce and Animal By-products Import and Export Corporation to import oolong tea into Japan. It records developing a canned oolong tea in 1980 and selling it across Japan from 1981; developing a canned green tea in 1984 and starting to sell it in 1985; renaming that product Oi Ocha in 1989; and launching Oi Ocha in 500 ml PET bottles in 1996, alongside a patented production method for PET-bottled green tea. Every date in this paragraph is the company's own, from a page retrieved and read, and none of it is TeaHQ's reconstruction.
Where the 1990 date comes from, and why this page does not use it
Attested in the historical record, and sourced to it.
The date most often printed for the world's first PET-bottled green tea is 1990, and it is repeated widely enough to look settled. It is not on the manufacturer's own timeline. That timeline has no 1990 entry at all — the decade runs from 1989 straight to 1992 — and the PET launch it does record is 1996. TeaHQ has not found a document supporting 1990 and does not assert that 1990 is wrong; it may refer to a container the company does not list, or to somebody else's product. What can be said is where each figure comes from, so this page carries 1996 on the company's authority and records the 1990 date as circulating without a source TeaHQ has been able to retrieve.
Why cold unsweetened green tea was a hard thing to put in a can
TeaHQ's own reading of well-attested general knowledge, with no single source behind it.
The obstacle is oxygen and it shows up as colour before it shows up as flavour. Green tea liquor held warm in a sealed metal container in contact with air browns, and the fresh vegetal aroma that is the whole point of the drink flattens into something stewed. Sweetened drinks hide that; unsweetened green tea has nothing to hide behind. The manufacturing answer was to displace the oxygen from the headspace before sealing, which is what ITO EN's T-N Blow process is described as doing, and to control the process afterwards so the liquor stays clear rather than throwing a haze when it is chilled. That is why the category arrived in the order it did — oolong first, which browns less visibly, then green tea — and why the enabling event was a packaging problem being solved rather than a taste being discovered.
What it changed about how tea is drunk
A description of something people do now, compiled from published accounts rather than from practice.
Three things, and all of them are visible in ordinary life rather than in the trade press. Tea became a cold drink by default for a large part of its market, which had not been true anywhere outside the American South and a few other places. It became portable in a way a flask of leaf is not, so it competes with soft drinks and bottled water rather than with a pot at home. And because the unsweetened version won in Japan, tea kept its identity as a plain drink there instead of becoming a sugar delivery system, which is the opposite of what happened to the same category in the United States. The format is not neutral: it decides who is drinking, when, and next to what on a shelf.
The priority claims here are the company's, and are recorded as such
TeaHQ's own reading of well-attested general knowledge, with no single source behind it.
ITO EN describes its 1980 product as the world's first canned oolong tea and its 2000 line as the industry's first heatable PET bottles. Those are claims about a market rather than about the firm, and a firm is not a disinterested witness to its own priority. TeaHQ has not sought or found independent confirmation of either, so neither is asserted as fact anywhere on this page; they appear only as things the company says about itself. The launch dates are a different matter — nobody has a better record of when a company started selling something than the company — and those are carried on its authority.
What TeaHQ does not have on this subject
TeaHQ's own reading of well-attested general knowledge, with no single source behind it.
A great deal, and it is worth naming rather than implying. There is no verified chronology here for the American bottled-tea business, which is a large industry with a quite different product — mostly sweetened, mostly black, mostly sold at ambient temperature in the same aisle as soft drinks. There is none for Taiwan's or mainland China's bottled market, which are enormous and moving fast. There is no production or sales figure for the category anywhere in TeaHQ's statistics register, because no publisher TeaHQ has retrieved breaks tea out that way. This page is one manufacturer's chronology and TeaHQ's reading of what the format does, and it should not be read as a history of the category.