Author Archives: Sónia Fiuza

Author: Sónia Fiuza

PhD in Biochemistry and professional researcher, with focus in metabolism and toxicity. Head of tea education at CFER. Expert in the service, tasting and production of tea, focusing on the study of its functional and sensorial characteristics. Tea sommelier by the International Tea Masters Association. Advanced knowledge in Chinese and Japanese teas, with expertise in tea handling by the Intertee Academy.

Tea can be consumed in different ways. The most popular one worldwide continues to be the infusion of the dried leaves, however, solid tea consumption is growing remarkably, especially due to the new matcha (powdered tea) consumption trend. Actually, tea was firstly consumed as a whole leaf instead of simply as an infusion. The leaves were not strained and tossed as we do now, and this allowed the consumers to take advantege of all of the nutricional aspects of the tea leaf, both the water soluble and the insoluble ones.

We might say that we are still in the leaf infusion Era and regarding this matter many questions usually arise. Which one is the best? To use loose leaf or tea bags?

Both have advantages and disadvantages.

Comparing tea quality

Generally loose leaf tea is of better quality than tea sold in tea bags, especially reagarding cheap tea bags, which contain mostly tea dust and tea fannings resulting from the tea leafs processing. However, there are many good quality tea bags which use either tea sourced from cut loose tea leasf instead of the byproducts of the tea industry and some top quality brands that even sell tea bags containing full tea leaves. I usually advise loose leaf tea for heavier tea drinkers as the tea sold in this fashion is hermetically sealed until use, unlike tea bags which can lose flavour and absorb smells very easily.

A common habit, even at speciality stores, is to open the tea container and give it to the client to smell. This is not hygienic at all and should be avoided. In this regard hermetically sealed tea bags can better preserve their flavour than frequently opened tea containers. If you can afford good quality tight containers or are a rather heavy consumer of loose leaf tea this shouldn’t however pose as big as a problem.

An advantage of brewing loose leaf tea is that you can see the beauty of the leafs unfold in hot water, admire how they look like before and after brewing and how they smell. You can also play with the amount of tea you wish to brew making it lighter or stonger. When using tea bags you can play with the flavour only by modulating either the water temperature or the infusion time.

When brewing loose leaf it implies you to have more specialized tea paraphernalia and time. Usually people more inclined to loose leaf teas invest more time in tea education and look for the perfect cup.

Tea bags are normally of a lower quality when comparing to loose, hermetically sealed tea.

Regarding tea bags a lot of debate has been made about the type of tea bag. Many advocate that the pyramidal tea bags are the best as they allow more room for the leaves to expand. While some say this is more of a marketing stategy, there are a few scientific reports regarding the loose leaf vs. tea bag “battle”. A recent study compared single, double and circular tea bags with loose leaf tea. What was found was that indeed leaf swealling is higher for loose leaf, followed by double chamber tea bags, single tea bags and circular tea bags. In another study, researchers found that, althought the kinetics of goodies, i.e., polyphenol content had a faster release time in tea leafs, and independent of infusion time, when adressing tea bags, the polyphenol content was dependent on the infusion time, probably due to the swelling rates verified by the comparing research group. At the end of the day, it all boils down to tea quality.

Would you rather have low quality loose leaf tea or good quality bagged tea? Common sense is always the key? What is you way of brewing tea?

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Sources

J Food Sci Technol. 2017 Jul;54(8):2474-2484. doi: 10.1007/s13197-017-2690-9. Epub 2017 May 18. “Swelling and infusion of tea in tea bags.”
Avicenna J Phytomed. 2016 May-Jun;6(3):313-21. “Effect of different brewing times on antioxidant activity and polyphenol content of loosely packed and bagged black teas (Camellia sinensis L.).”

Tea is a passion. Tea is an experience and an endeavor to untraveled worlds. I asked myself what would I say If I only had one chance to talk to people about tea? The present piece is the combination of what I love, with who I am, a biochemist concerned with nature, animals, and people, for a better world.

After water, tea is the most consumed beverage worldwide. The tea plant is native to China and it has been long known to Chinese for its medicinal properties. In fact, tea was used as a medicine in former times being adored by Emperors and recognized by Taoists and Buddhists as a precious element in ones’ lives. Nowadays, tea has also been recognized by the scientific community as a substance with outstanding health properties and benefits, with thousands of scientific papers being published throughout the years. Tea health benefits include, but are not limited to, cardioprotective effects, antioxidant, anticarcinogenic and antimicrobial properties. However, concerns about tea consumption are also rising within the literature. Tea health concerns are essentially related to the presence of pesticides and Fluoride (F).

The high temperatures involved in the brewing of tea may extract more contaminants from the plant into the drinking water.

Pesticides are used to prevent tea crop diseases and the attack of some tea loving insects to improve the yield of the crop and the farmers’ profit. Some of the reported negative effects on human health related to the exposure to pesticides during normal daily life habits involve gastrointestinal, neurological, carcinogenic, respiratory and reproductive problems. Pesticides are of special concern in tea due to several reasons.

The organic choice

Tea is a highly sensitive crop and therefore a heavy mix of different pesticides can be used to preserve it. As the leaves are not washed prior to processing, residues present on their surface are not removed. Also, since tea is brewed at high temperatures, the extraction of pesticides into the drinking water is high. Additionally, as some teas are consumed in powder, like matcha, the whole leaf is ingested, making sure that not only the water-soluble pesticides are ingested, but also the less or non-water-soluble ones as well.

On the other hand, fluoride accumulates in tea plants after being absorbed from the soil. The ingestion of F has been related to hypothyroidism, neurotoxicity, fluorosis, arthritic disease, and musculoskeletal disorders. Fluoride accumulates mostly in tea leaves, especially inside the old ones. Fluoride is quite soluble in water and will easily be present in your favorite cup of brewed tea.

As there is not yet an ideal balance between the economic interests and health protection, is there something we can do to avoid the exposure to these tea contaminants and benefit from the remarkable health properties attributed to tea? Yes! Definitely!

Organic teas are the best choice when you do not know where your tea is coming from. Besides being controlled for pesticides, organic teas have also shown lower levels of fluoride. A direct relationship has been found between low quality tea and higher concentrations of F. In the case of tea, the price is generally a good indicator of its quality.

If you brew your own tea at home, you can drink a cup of tea for as cheap as 0.05€ a cup, sometimes even cheaper than a cup of bottled water! Cheaper tea, usually available to the mass market, is made from the oldest and lower quality leaves, which means they most probably have a high fluoride concentration.

Alternative ways to minimize the ingestion of contaminants

Different types of tea, such as white tea made with the youngest leaves, can also be naturally absent from fluoride, as it tends to accumulate in old leaves. If you still have old batches of tea that you don’t want to waste, you can always try to minimize the concentration of contaminants by washing your tea. There is an old tradition when drinking loose leaf tea which consists of rinsing and discarding the first water in contact with the tea leaves. This process started many centuries ago when tea processing was not quite refined as now, and it aimed at washing off dirt or dust.

Considering fluoride and the solubility of some pesticides in water, if you are drinking non-organic, poor quality tea, rinsing the tea first can be a good option already proven by some studies to reduce the level of contaminants, although not 100% efficient, and at the expense of major flavor loss when dealing with low quality teas.

Choosing a good quality organic tea is still your best option. 

As a concluding remark, although not faced with Hamlet’s striking dilemma on life or death, when confronted with:

To tea, or not to Tea?

My answer is: To Tea with Education.

Sources

Tea and Health: Studies in Humans (2013) in Current Pharmaceutical Design
Chemical Pesticides and Human Health: The Urgent Need for a New Concept in Agriculture (2016)
In Frontiers in Public Health
Worldwide Regulations of Standard Values of Pesticides for Human Health Risk Control: A Review (2017)
in International Journal of Environmental Research and Public Health
Fluoride content in tea and its relationship with tea quality. (2004)
in Journal of Agriculture and Food Chemistry
Black Tea Source, Production, and Consumption: Assessment of Health Risks of Fluoride Intake in New Zealand (2017)
In Journal of Environmental and Public Health