Table of Contents
Journal of Food Processing
Volume 2014 (2014), Article ID 824050, 9 pages
http://dx.doi.org/10.1155/2014/824050
Research Article

Effects of Microwave Pretreatment of Apple Raw Material on the Nutrients and Antioxidant Activities of Apple Juice

College of Food Science, Shanxi Normal University, 1 Gongyuan Street, Linfen 041004, China

Received 14 July 2014; Revised 18 August 2014; Accepted 19 August 2014; Published 26 August 2014

Academic Editor: Franco P. Pedreschi

Copyright © 2014 Shaoying Zhang and Rui Zhang. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Microwave technology has been widely applied in food processing. To investigate the effects of microwave pretreatment of raw material on the nutrients and antioxidant activities of apple juice, the apple materials were treated with 90, 270, 450, 720, and 900 W microwave at 25, 50, 75, 100, and 125 s, respectively. The results showed that after the raw materials were treated with microwave, the vitamin C, amino nitrogen, and anthocyanin content decreased, and the total flavonoids and polyphenol of apple juice increased. Further, the total polyphenol of apple juice originating from raw material treated with 900 W microwave through 75 s was 115% higher than that of control samples. The antioxidant activities of prepared apple juice increased in terms of diphenyl-picryl hydrazyl, superoxide anion and hydroxyl radical scavenging capacity, reducing power, and iron chelating activity. So appropriate microwave pretreatment of apple raw material could increase some specific nutrients and enhance the antioxidant activities of apple juice.