Abstract

Green tea is an unfermented tea containing a higher quantity of bioactive components. It has received a great deal of attention due to many biological activities, such as antioxidative, anticarcinogenic and antitumour activities. However, deterioration in quality after heating processes, in particular sterilization, was technical barrier for commercial ready-to-drink green tea production. It has already been demonstrated that pulsed electric fields (PEF) processing can alternatively be applied to deliver safe and shelf-stable products. In this paper the effect of conventional heat treatment (121 ^oC, 3min) and PEF treatment on the bioactive components (polyphenols, catechins and free amino acids) and color of green tea infusions was studied. There was a significant (P<0.05) decline in polyphenols, total catechins and total free amino acids induced by heat treatment, and the green tea infusions darkened and became less green and deeper yellow after the heating. Compared to heat processing, PEF can efficiently retain the bioactive components and original color of green tea infusions.

Submitted: November 14, 2007 · Accepted: August 7, 2008 · Published: August 13, 2008

Recommended Citation

Wang, Mo; Yang, Ruijin; and Zhao, Wei (2008) "Effects of Heat and Pulsed Electric Fields on Bioactive Components and Color of Green Tea Infusions," International Journal of Food Engineering: Vol. 4 : Iss. 5, Article 11.
Available at: http://www.bepress.com/ijfe/vol4/iss5/art11