Evaluation of seven different drying treatments in respect to total flavonoid, phenolic, vitamin C content, chlorophyll, antioxidant activity and color of green tea (Camellia sinensis or C. assamica) leaves

The effect of seven drying treatments (sun, shade, oven 60 °C, oven 80 °C, oven 100 °C, microwave and freeze-drying) were evaluated with respect total flavonoid (TFC), phenolic (TPC), antioxidant activity, vitamin C and color characteristics of green tea. In general, drying increased antioxidant act...

Full description

Saved in:
Bibliographic Details
Published in:Journal of food science and technology 2016-01, Vol.53 (1), p.721-729
Main Authors: Roshanak, Sahar, Rahimmalek, Mehdi, Goli, Sayed Amir Hossein
Format: Article
Language:English
Subjects:
Analysis
Antioxidants
Chemistry
Chemistry and Materials Science
Chemistry/Food Science
Chlorophyll
Flavonoids
Food preservation
Food products
Food Science
Free radicals
Freeze drying
Green tea
Microwave heating
Microwaves
Nutrition
Original
Original Article
Phenols
Quality
Studies
Tea
Temperature
Vitamin C
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The effect of seven drying treatments (sun, shade, oven 60 °C, oven 80 °C, oven 100 °C, microwave and freeze-drying) were evaluated with respect total flavonoid (TFC), phenolic (TPC), antioxidant activity, vitamin C and color characteristics of green tea. In general, drying increased antioxidant activity, TPC, TFC and chlorophyll content, while it led to a decrease in vitamin C. The highest TPC (209.17 mg Gallic acid/gdw) and TFC (38.18 mg Quercitin/gdw) were obtained in oven drying at 60 and 100 °C, respectively. Among methods, oven drying at 60 °C revealed the highest radical scavenging activity (IC 50  = 167.166 μg/ml), while microwave showed the lowest one (IC 50  = 505.5 μg/ml). Similar trend was also observed in reducing power assay. The highest vitamin C (16.36 mg/100gDM) and Chlorophyll a (17.35 mg/l) were obtained in freeze drying. Finally, sun and freeze drying methods were considered as the least and the most desirable drying methods, respectively the final color of green tea leaves.
ISSN:0022-1155
0975-8402
DOI:10.1007/s13197-015-2030-x