- This topic has 4 replies, 4 voices, and was last updated 14 years, 2 months ago by
Leo.
-
AuthorPosts
-
-
2011.09.08 at 3:02 pm #8368
Tea Man Bill
ParticipantAlbeit the set up of this forum, questions, comments and encouragements keep coming to us through the email forms. This question is an interesting one so we are quoting it below hopefully to draw some ideas:________________________________________________________________________Firstly, I want to thank you for this site. I found it today and have already spent hours perusing your wealth of detailed and seemingly objective knowledge regarding tea. I serve tea for a living and lead casual cuppings regularly, so knowing this uncommon information is immensely helpful.I also had a specific question regarding the weight loss article at https://www.teaguardian.com/health/fight_obesity_2.html.How much, if any, of the EGCG content is retained with infusions subsequent to the first? I regularly re-infuse my oolongs (and certain greens) and enjoy the ability to continue drinking tea with minimal caffeine and developing flavor. Thus, it would be convenient to do this for weight loss as long as EGCG continues to be released.Thanks for your time and again for this wonderful resource. -
2011.09.28 at 1:31 pm #8800
Alexargon
Participant<FONT face=Calibri>I think it’s impossible to know the exact quantity of EGCG in a cup of tea. Variables are too many even if you keep constant the type of tea and the infusion parameters used: maybe you have a tea quality (or grade) I have not or the storage of your tea has been different from mine. I also think it is not a so usefull information… I mean, the study at which you refer is not performed on the entire population, but in a small 132 subgroup of people with a particular characteristic (over-weight): maybe you are able to respond the treatment in same way with a lower dosage, or you may need an higher one (in terms of pharmacology). The same applies for antioxidant activity only or cardiovascular benefits, as examples.Anyway, tea catechins release follows a common behaviour: – Higher the temperature of the water, higher the catechins release- Longer the infusion time, higher the catechins release. That means you’ll find a greater amount of them in infusions subsequent to the first. Only here, the opposite is for caffeine, althought for certain green teas the story can be different.You can also know when your tea has stopped giving you those compounds: catechins give colour, flavour and (if in great amount) astringency and bitterness. I know these last two are less good at the tongue of someone, but these infusions are the richest in catechins.To sum up, infusions subsequent to the first are richer in catechins, that reach a maximum when you start to feel the liquor much more astringent (or bitter) and then disappear over subsequent infusions (flavour start to become watery).</FONT>
-
2011.10.01 at 2:09 am #8802
Hokusai
ParticipantI agree that the higher the temperature, the more release of EGCG, but I think the amount of EGCG released in which infusion does not depend on which number of infusion but rather on the duration of each. The tea variety also affect the pattern of release significantly.
-
2011.10.06 at 2:37 pm #8811
Leo
ParticipantProvided that the temperature of water used and the duration of infusion are both about the same, then the amount of catechins dissolved should be proportionally lessened in each round. Alexargon suggested that it should be more towards latter rounds maybe because usually the tea is more bitty, tar, or bitter towards the end. That is a matter of the proportion of dissolvable matters in the tea. The sugars, amino acids, aromatic substances etc are much less than catechins in tea, particularly green, oolongs etc so they are used up in the prior rounds of infusion. Not much left proportionally to the catechins. The tea thus tastes more spiky.
-
2011.10.06 at 2:39 pm #8812
Leo
ParticipantI forgot: read the article:
https://www.teaguardian.com/health/EGCG_oolong_gongfu.htmlI used only one report for the argument, I hope that suffice for the topic
-
-
AuthorPosts
- You must be logged in to reply to this topic.
