Effects of Drying Methods and Tea Preparation Temperature on the Amount of Vitamin C in Indian Gooseberry Tea

Abstract

Indian gooseberry is a rich source of vitamin C. The fruit can be consumed either fresh or after processing into different products including Indian gooseberry tea. Both drying and tea preparation steps affect quality of the gooseberry tea drink made using dried gooseberry. This study investigated the effects of different drying methods, i.e., hot air drying, vacuum drying, and low-pressure superheated steam drying, on the retention and degradation of vitamin C (in terms of the total ascorbic acid content, TAA) in dried gooseberry flakes. In addition, the effect of temperature of water used to prepare the tea on the release of TAA and on its later degradation was also investigated.

Keywords:

• Ascorbic acid
• Hot air drying
• Leachability
• Low-pressure superheated steam drying
• Porosity
• Release kinetics
• Vacuum drying

ACKNOWLEDGEMENTS

The authors express their sincere appreciation to the Commission on Higher Education, the Thailand Research Fund (TRF), the National Research Council of Thailand and the International Foundation for Science (IFS, Sweden) for supporting the study financially.

Notes

Different letters in the same column indicate that values are significantly different (p < 0.05).