Antioxidants in Tea

Most people know that tea is a pretty good source of antioxidants, specifically polyphenols or flavonoids. However, there was a study done back in 2010 by researcher Shiming Li that concluded many bottled teas have “virtually no” antioxidants (click here for study). Six teas were analyzed in this study and those teas contained 81, 43, 40, 13, 4, and 3 milligrams of polyphenols per 16-ounce bottle. I have been looking, but I have not been able to find which specific brands and types of tea were actually tested.  To put those amounts into perspective, here are some numbers for comparison:

Lipton loose black tea (home brewed) – 175 mg of polyphenols per 8 oz (according to Lipton)
note: this is a pretty average amount for a home brewed tea
Lipton Mardarin Orange Green Tea (home brewed)- 120 mg per 8 oz (according to Lipton)
Lipton Cold Brew Iced Tea -78 mg polyphenols per 8 oz (according to nutrition facts on Kmart.com, unable to verify elsewhere or through Lipton)
Chipotle’s (S&D brand) Iced Tea – 115mg per 8 oz
Cranberry Juice – 52 mg of polyphenols per 8 oz
Wild Blueberries – 836 mg per 100 mg (about 2/3 cup)

There is another article I came across in a 2011 Prevention magazine (click here) on the subject that came to a somewhat different conclusion. This study found many bottled teas they tested were “good” sources of antioxidants.  One tea (Nestea Liquid concentrate green tea with honey) they even found to be an “excellent” source of antioxidants.  They didn’t, however, give any mg amounts for the antioxidant content like the previous study did.  This study also found the differences in antioxidant levels between green and black tea or between hot versus cold brewed tea to be minimal.

Most studies do show that tea that you brew at home (either hot or cold brewed) is almost always going to have more antioxidants than bottled or “ready to drink” teas.  It seems like some of this difference has to do with the processing of bottled tea and some has to do with the types of tea leaves that are used in bottled tea.  Also teas that have added flavors are likely to have less antioxidants simply because they will typically contain less actual tea.

I was, and still am, very interested in finding out how much polyphenols specific bottled teas contain (mainly the bottled teas I have reviewed here). I have done some research, but I have found minimal information on most of these brands.  According to livestrong.com, unsweetened Lipton Pure Leaf bottled tea contains 90mg of flavonoids per 8 oz serving. I find this a little hard to believe and I haven’t been able to verify this information anywhere else. Lipton currently makes no claims to the amount of antioxidants in their Pure Leaf bottled tea.

I did personally reach out to Tejava, in hopes of finding any information on the polyphenol content of its tea. I was very impressed with how quickly they returned my inquiry, even if I didn’t get the information I had hoped.  The response I got from Tejava made it clear that they make no claims about how much antioxidants or polyphenols their tea contains. Here is their response on the subject:

“We do not make any claims for the polyphenol or antioxidant content of Tejava because they are naturally occurring in Tejava and we do not add any as an ingredient as do many bottled teas on the market. Tejava is made from just the Java tea leaves we buy and filtered water. Natural and seasonal variations in the leaves as well as minute changes in the brewing process can affect the overall polyphenol and antioxidant content of the brewed tea. For these reasons and the fact that even home brewed teas widely vary, I’m sure you can see now why we cannot more succinctly address your request.”

In addition to asking about the polyphenol content of Tejava, I also was curious if there was a way to tell when their tea was brewed or bottled.  I read some information that seemed to indicate that antioxidant levels begin to go down after a tea is brewed.  So the more time that has elapsed between when a tea is brewed and when it is consumed, the lower the antioxidant levels.  I have since not been able to find any data to confirm this, so I am not positive it is correct.  Having said that, I did find Tejava’s response useful and interesting (I have adjusted the numbers in the example to fit my picture) :

“Every bottle of Tejava Premium Iced Tea always includes a date code which indicates the date and time the Tea was bottled. The production code is located on the label above the ingredients and sometimes stamped on the neck of the bottle itself. For example, our code:

5BT 295 0822

Photo Jan 15, 7 49 04 AM indicates that the bottle was filled on October 22nd, 2015 at 8:22 am. The first number represents the year – 2015. All bottling in 2016 will start with a 6 (2014= 4). The second set of numbers represents a Julian calendar date, which is the 295th day of the year – October 22nd. A letter and number represent the batch and the last set of numbers represents the time of production using a 24 hour clock – 8:22 am.

We believe that our Tejava Premium Iced Tea tastes best within two years of bottling. Therefore, Tejava bottled on October 22nd, 2015, would not “expire” until October 22nd, in the year 2017.”

Lastly I was curious how Tejava got away without using any preservatives like so many other bottled teas. Here was their response to that:

“I would like to assure you that our Tejava® Premium Iced Tea is fully pasteurized under very carefully controlled conditions at our bottling facility. We do not use preservatives. Our facility is in fact a licensed cannery and each batch of Tejava that we bottle is examined by an inspector from the State of California Department of Health Services, Food and Drug Branch. This inspection is performed to ensure that the pasteurization process operates under optimal conditions, and it is the same type of inspection performed at other food processing plants that prepare canned vegetables, canned meats and other food items.”

I was very impressed with Tejava’s thorough and quick response from their customer service department and has made me like their product even more.

I do plan on attempting to do some tests on my own on antioxidant levels for various teas. I admit I may be getting in over my head, but I have found what appear to be reliable methods online for getting a general idea of antioxidant content. Check back in a few months and hopefully I will have some more information on the subject.

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