Factors Affecting Polyphenol Content and Composition of Fresh and Processed Tea Leaves

Year 2009, Volume: 7 Issue: 6, 29 - 40, 01.12.2009

Nihal Turkmen Ferda Sarı Y. Sedat Velioglu

Abstract

Tea has been consumed literally for thousands of years and is recognized as a major source of polyphenols in human diet. Polyphenols comprising 20-40% of dry matter in young tea shoots are very important constituents of tea from an intrinsic quality point of view. They are responsible for the colour, flavour and brightness of tea. Recently, tea polyphenols have become a subject of intense studies by scientists throughout the world because of their health beneficial effects and potential uses. On the other hand, there are numerous factors affecting polyphenol structure of tea leaves, such as tea leaf variety, harvesting season, climate, processing method and analytical method. This review is presenting factors affecting polyphenol content and composition of in fresh and processed tea leaves, i.e., green and black teas

Keywords

Leaf handling, Leaf age, Leaf variety, Harvest methods, Season, Processing

Taze ve İşlenmiş Çay Yapraklarındaki Polifenol Đçeriği ile Dağılımına Etki Eden Faktörler

Abstract

Binlerce yıldır tüketilmekte olan çay, diyette polifenollerin ana kaynaklarından biridir. Polifenoller taze çay yapraklarında kuru maddenin %20-40’ını oluşturur ve çay kalitesinin en önemli ögelerinden biridir. Polifenoller çayın renk, lezzet ve parlaklığından sorumlu bileşiklerdir. Son yıllarda çayın sağlık üzerindeki olumlu etkilerinin ve potansiyel kullanım olanaklarının ortaya çıkmasından sonra çay polifenolleri üzerinde daha yoğun olarak çalışılmaya başlanmıştır. Çayın polifenol yapısını etkileyen çok sayıda faktör bulunmaktadır. Bunların başlıcaları çay yaprağı varyetesi, hasat dönemi, işleme yöntemi ve uygulanan analiz metotlarıdır. Bu makalede taze çay yapraklarının ve bunlardan işlenen yeşil ve siyah çayların polifenolleri üzerine etki eden faktörler irdelenmiştir

Keywords

Yaprak toplama, Yaprak yaşı, Çay yaprağı varyetesi, Hasat yöntemi, Sezon, Proses

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