綠茶風味甘藷產品之開發

Development of Green-Tea Flavor Sweet Potato Product

本研究以綠茶浸漬甘藷，嘗試開發具有綠茶風味的甘藷產品。試驗結果顯示，將微波處理之甘藷浸於不同糖濃度的綠茶後，隨著糖濃度的增加，甘藷中所含之總酚的含量也隨之減少。隨著浸漬時間的增加，在總酚、清除DPPH自由基能力、FRAP（血漿三價鐵還原力）方面，都會有顯著提高的現象，但在類黃酮方面其上升的量並不多。甘藷浸於無糖綠茶3hr後，其抗氧化能力為最高，但在感官品評上由於其澀味重，並不被品評員接受；隨著浸漬時間的增加，甘藷浸漬於無糖綠茶中會有較濃的茶香味、茶味和澀味。而整體接受度以30°Brix的綠茶浸漬甘藷，最受品評員所接受。於4℃下儲藏21天後，綠茶風味甘藷總生菌數、酵母菌和黴菌含量尚符合CAS驗證基準。

The objective of this study was to develop green-tea flavor sweet potato product. Results indicated that the total phenol content was decreased with the increasing sugar content of microwave sweet potato after soaking in different °Brix green tea. The content of total phenol, DPPH radical-scavenging ability and FRAP (ferric reducing ability of plasma) capability were found increasing with the soaking time except flavonoids content. Besides, microwave sweet potato soaked in no sugar green tea for three hr to exhibit the highest antioxidant activity but its overall acceptance was lower because of its heavy astringent taste. The microwave sweet potato soaked in no sugar green tea had the heavy tea aroma and tea taste but also showed the astringent. The microwave sweet potato soaked in 30 °Brix green tea obtained the most accepted by the panelists. The total bacterial count, yeast and mold of green-tea flavor sweet potato is still consistent with Chinese Agricultural Standards (CAS) validation benchmarks after storing at 4℃ for 21 days.