Albino Tea Cultivars

In recent days, my attention was drawn to a particular cultivars of tea: the albino tea cultivar.
I accidentally discovered the existence of this type of cultivars, then intrigued I started looking for it was anything special compared to the other cultivars of Camellia Sinensis.

There are two main types of albino cultivars, light-sensitive and another thermosensitive.
The light sensitive albino cultivar manifested most clearly its characteristics when it is more exposed to light, in fact the leaves of these plants are clearer precisely in summer when the light exposure is stronger.

Leaves belonging to a light-sensitive albino tea cultivar. For ten days a part of the leaf has been less exposed to sunlight. As you can observe as you can see this part of the leaf has become greener, indicating greater amount of chlorophyll. Fonte:Effect of sunlight shielding on leaf structure and amino acids concentration of light sensitive albino tea plant Wang K. R. 1,2 , Li N. N. 1 , Du Y. Y. 1 and Liang Y. R. 1. African Journal of Biotechnology

Leaves belonging to a light-sensitive albino tea cultivars. For ten days a part of the leaf has been less exposed to sunlight. As you can observe as you can see this part of the leaf has become greener, indicating greater amount of chlorophyll.
Fonte:Effect of sunlight shielding on leaf structure and amino
acids concentration of light sensitive albino tea plant
Wang K. R. 1,2 , Li N. N. 1 , Du Y. Y. 1 and Liang Y. R. 1. African Journal of Biotechnology

The other type (thermosensitive) manifests a greater albinism when the temperature is lower.
The tea leaves belonging to a thermosensitive albino cultivar develop in three stages.
The  pre-albinistic stage, albinistic stage and the regreening stage.
The pre-albinistic stage includes the budding and phase just next to it which is in spring with a temperature lower than 20 ° C, at this stage the leaves are light green. With the passage of time the leaves turn more and more white reaching the albino stage. With the approach of summer, however, temperatures rise and the leaves turn green again (regreeing stage), usually that happens when the temperature exceeds 22 ° C.

The leaf of a thermosensitive albino cultivar develops in three stages. The pre-albinistic stage (a), albinistic stage (b) and regreening stage (c). Fonte: Proteomic analysis of young leaves at three developmental stages in an albino tea cultivar Qin Li , Jianan Huang , Shuoqian Liu , Juan Li , Xinhe Yang , Yisong Liu and Zhonghua Liu.

The leaf of a thermosensitive albino cultivar develops in three stages.
The pre-albinistic stage (a), albinistic stage (b) and regreening
stage (c).
Fonte: Proteomic analysis of young leaves at three
developmental stages in an albino tea cultivar
Qin Li , Jianan Huang , Shuoqian Liu , Juan Li , Xinhe Yang , Yisong Liu and Zhonghua Liu.

Different teas on the market come from the albino varieties, among which some are Anji Bai Cha and Bai Ji Guan.

Leaves of cultivar Anji baicha during the various stages of albinism. This cultivar is characterized by a thermosensitive albinism. Fonte: Xiong L, Li J, Li Y, Yuan L, Liu S, Huang JA, Liu Z: Dynamic changes in catechin levels and catechin biosynthesis-related gene expression in albino tea plants (Camellia sinensis L.). Plant Physiol. Biochem. 2013

Leaves of cultivar Anji baicha during the various stages of albinism. This cultivar is characterized by a thermosensitive albinism.
Fonte: Xiong L, Li J, Li Y, Yuan L, Liu S, Huang JA, Liu Z: Dynamic changes in
catechin levels and catechin biosynthesis-related gene expression in albino
tea plants (Camellia sinensis L.). Plant Physiol. Biochem. 2013

As you can guess the leaves of these plants are lighter because of the smaller amount of chlorophyll.

As a result of this lower content of chlorophyll the plants belonging to this cultivars to try to maintain a good photosynthetic capacity produce a large amount of zeaxanthin (much more compared to other cultivars) a carotenoid that is capable of absorbing solar radiation in excess, They would otherwise damage the plant. This carotenoid has a yellow colour and being vary abundant this molecule will have an impact on the color of the leaf that has a color to yellow.

What instead determines a particular taste in these teas is the large amount of free amino acids (especially theanine) present. As mentioned in a previous post the theanine gives a strong umami taste to the brew that fact is clearly perceptible even in this type of tea. In addition, the theanine in liaison with caffeine also has positive effects on mental focus.
The particular abundance of this kind of molecules is closely linked to the lack of chlorophyll. In fact the amino acids in the plant by binding between them serve as bricks to build various proteins, but in this cultivar protein production is reduced due to the decrease of chloroplasts and photosynthetic pigments, so the amino acids present in the leaf do not use them all from the plant, a good amount remains free (ie, the amino acids are not bound to each other) and therefore capable of giving the pleasing effects above.

Another feature of this tea cultivar is to have in general a lower amount of polyphenols which makes the tea very little astringent, in fact, as we remember the astringency is mainly caused by this type of compounds.
Personally I think almost certainly the lack of polyphenols also have an influence on the final color of the infusion of these teas making it clearer than others, but not having  bibliographic evidence I can not be quite sure (because the color of the infusion depends a lot from how the tea is processed).

The amount of caffeine is less in tea belonging to this cultivar. Also this feature is due to albinism but in this case the mechanism by which this occurs is quite complex.

References:

Determination of quality constituents in the young leaves of albino tea cultivars.
Feng L, Gao MJ, Hou RY, Hu XY, Zhang L, Wan XC, Wei S.

Effect of sunlight shielding on leaf structure and amino
acids concentration of light sensitive albino tea plant
Wang K. R. , Li N. N. , Du Y. Y. and Liang Y. R. 1. African Journal of Biotechnology.

Proteomic analysis of young leaves at three developmental stages in an albino tea cultivar.
Qin Li , Jianan Huang , Shuoqian Liu , Juan Li , Xinhe Yang , Yisong Liu and Zhonghua Liu.

Comparison of the Quality Characteristics of4 Albinos Tea.
Ronglin Li, Zhengzheng Li, Yiyang Yang, Hao Yuan, Yunlong Kong.
Food and Nutrition Sciences, 2013, 4, 1102-1107.

 

Annunci

Un pensiero su “Albino Tea Cultivars

Rispondi

Inserisci i tuoi dati qui sotto o clicca su un'icona per effettuare l'accesso:

Logo WordPress.com

Stai commentando usando il tuo account WordPress.com. Chiudi sessione / Modifica )

Foto Twitter

Stai commentando usando il tuo account Twitter. Chiudi sessione / Modifica )

Foto di Facebook

Stai commentando usando il tuo account Facebook. Chiudi sessione / Modifica )

Google+ photo

Stai commentando usando il tuo account Google+. Chiudi sessione / Modifica )

Connessione a %s...