Study on the contents of antioxidant capacity and PMFs by different drying temperatures and nano treatments for Mucrott

• Main Authors: Wan-Ting Tu, 涂菀婷
• Other Authors: Ho-Hsien Chen
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/43523741572588600537

碩士 === 國立屏東科技大學 === 食品科學系所 === 98 === Mucrott belongs to Rutaceae family, which is produced abundantly in winter season. Murcott is rich in juicy and tastes delicious, but discarded peel is just regarded as waste. In fact, the peel of Mucrott can be dried to make Chenpee, which is popular in folk medicine. In this study, Mucrott peel and whole Mucrott were used to dry at different hot-air drying temperatures (50℃, 60℃, 70℃) and then were analyzed for their physical and chemical properties. Samples were also ground up by a nano wet-grinding machine, and then analyzed their total polyphenolic contents, total flavonoid contents, TEAC, and scavenging DPPH capacity. Nobiletin and tangeretin contents in polyflavonoid flavones before and after nano treatment were also studied. The results showed that the higher drying temperatures had the shorter drying time. Among of them the shortest drying time is in 70℃. For physical and chemical properties, the results showed that it had no significant change in color and microstructure on peel, whereas, for whole Mucrott drying, their color and microstructure had significant different change. The higher drying temperature is, the deeper is in color and the more damage is to their microstructure. For antioxidant contents, the results indicated that nano wet-grinding could obtaine higher total polyphenolic and flavonoid contents. A similar trend came for antioxidant capacity. After a nano wet- grinding treatment, its TEAC and scavenging DPPH capacity were higher than that without a nano treatment. The results showed that by using nano wet-grinding treatment and identifying by HPLC and LC/MS, it would help to increase the content of nobiletin and tangeretin. Among them, the highest content for nobiletin and tangeretin were 4.725 mg/g and 1.881 mg/g, respectively. Accordingly, dried mucrott peel in all respects was better than whole dried mucrott. Due to the no significant different change in drying temperatures and to have a shorter drying time, thus, drying at 70℃ was chosen to use for Chenpee process. Combining with nano wet-grinding treatment, it could increase nobiletin and tangertin content, entirely. As a result, to utilize nano-wet grinding to increase nobiletin and tangeretin in mucrott was previlable.