How does commercial bottled tea last without preservatives?

I find that if I make a pot of iced tea, it tastes fine the first day but by the second day it is unpleasantly tannic. 2 weeks seems very optimistic.

--scott

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: