Effect of Solar Dehydration and Induced Phenolic Dynamics on the Structural, Textural and Color Properties of Asian White Radish (Raphanus sativus L.)

• Main Authors: Carlos Eduardo Hernández Aguirre, 卡洛斯
• Other Authors: Ho-Hsien Chen
• Format: Others
• Language: en_US
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/06221240229019748105

碩士 === 國立屏東科技大學 === 熱帶農業暨國際合作研究所 === 92 === This study determined the effects of solar drying and induced phenolic dynamics on the ultrastructural, textural and color properties of dehydrated Asian white radish (Raphanus sativus L.). Solar stimuli activated a complex network of phenolic metabolism pathways, which profoundly altered their roles in determining the organoleptic properties of texture and color. The effect of the control factors was analyzed by water activity (Aw), Textural Profile Analysis (TPA), ultrastructural observations (by SEM), color values (L*, a* and b*), and the phenolic profile variations (by HPLC). In general, solar dehydration of radish is regarded as a stress condition, which increased phenolic acids in their free form, while decreased those cell wall bound. The response varied with the combination of control factors and their levels. The induction of free soluble phenolic was associated with an antioxidative response observed by the extent of browning (decreased L*, and increased a* and b* values). Furthermore, radish’s textural variations were attributed to the solar-induction of 4-hydroxybenzoic acid (a major cell wall bound phenolic), which contributed to the maintenance of the cell wall ultrastructure and adhesion during the process. The Taguchi-Grey Relational Analysis was applied for a systematic evaluation of the effects of the control factor.