Vitamin C (ascorbic acid) is indeed a very good quality preserver even
at low dose - keeps color and flavor stable. It will not however
inhibit microorganisms at the normal level of incorporation in RTD
tea. Preservation (bug kill) is achieved either by heating the drink
in its bottle to pasteurization temperature (80 deg C), or
sterilization temperature (90 deg C plus). Pasteurization gives a
short shelf life and sterilization a long one. But RTD drink product
life in the bottle traditionally depends on a combination of the
preserving effects of acidity, sugar level, carbonation, permitted
bactericides, temperature after bottling and heating time - these are
juggled by the product developer to optimize flavor, maximize
keepability, and minimize cost of production. Product format also
influences the mix - until recently a PET bottle could only survive
pasteurization tempertaures. For a "nothing added" product containing
just water, tea and Vit C, its shelf life will depend on heating
alone, and as long heating destroys quality a better system has been
devised. This is "hot fill" - the liquid is quickly heat sterilized
in a vat or flash sterilized in seconds passing it along a thin heated
tube (no over long sterilizing times due to the insulation of the
glass bottle) then filled in a sterile room into pre sterilized
bottles and capped with sterile caps before emerging from the sterile
environment. This process is more expensive but gives a superior
product, and I would guess SN's retail tea was made thus. Difficult
to do this at home!

Nigel at Teacraft


On 28 Dec, 00:42, SN > wrote:
> Just had some bottled tea, and noticed the bottle says man: 6/15/2006,
> exp: 12/14/2007 *(...freshly 'expired' )
>
> The label of course says: "pure black tea, unsweetened, with no
> preservatives or anything else to stand in the way of clean, fresh
> taste and numerous health benefits."
>
> it does have vit C. but its not detectable (by me) in taste.
>
> One time i made a couple bottles of tea (without getting my hands in
> the liquid), stuck them hot in the fridge and maybe about 2 weeks they
> started to smell like they were going towards expiration...
>
> do they freeze them or is the little vit C so strong?