In the present study, the objective was to investigate the relationship between
bitter components and whether the bamboo shoots greening or not within Dendrocalamus hamiltonii Nees et Arn. ex Munro which is known for no bitterness taste and other verities of bamboo shoots. Taxiphyllin can be decomposed to hydrogen cyanide and p-hydroxybenzaldehyde. Hydrogen cyanide concentrations are high in the top of bamboo shoots, and get lower in the base of bamboo shoots. In greening bamboo shoots of Leleba oldhami Nakai, hydrogen cyanide concentrations are 3.12 mg/g•F.W in the top, 2.87 mg/g•F.W. in the middle, and 0.48 mg/g•F.W. in the base. But in etiolated bamboo shoots of Leleba oldhami Nakai, hydrogen cyanide concentrations are 0.44 mg/g•F.W in the top, 0.03 mg/g•F.W. in the middle, and 0.00 mg/g•F.W. in the base. Hydrogen cyanide concentrations have significant differences between greening bamoo shoots and etiolated shoots of Leleba oldhami Nakai. There are similar results in other verities. Like Dendrocalamus latifloxus Munro, and Leleba edulis Odashimo. However, there are very low hydrogen cyanide concentrations in Dendrocalamus hamiltonii Nees et Arn. ex Munro. The sensory evaluation, shows positive correlations between bitterness and accumulation of hydrogen cyanide. Besides, total phenolic compounds, free amino acids, and soluble proteins in Dendrocalamus hamiltonii Nees et Arn. ex Munro are lower than Leleba oldhami Nakai.本試驗擬調查筍出青與否之苦味物質變化，與不具苦味之甜龍筍進行比較，以確定甜龍筍無論出青與否均不具苦味的原因。紫杉氰醣苷分解後產物為氰酸 (HCN) 與對羥基苯乙醇腈 (p-Hydroxybenzaldehyde)，藉由測定氰酸含量，可得知紫杉氰醣苷的累積程度。竹筍氰酸濃度頂端最高，往下而遞減。出青綠竹筍氰酸濃度頂段 3.12 mg/g•F.W.、中段 2.87 mg/g•F.W.、底段 0.48 mg/g•F.W.；未出青綠竹筍氰酸濃度依序為 0.44、0.03、0.00 mg/g•F.W.。顯示綠竹筍出青與否對氰酸濃度有明顯之差異，而麻竹筍、烏殼綠竹筍、也有相同趨勢。然而甜龍筍無論出青與否，在各部位氰酸累積均極低，在官能品評上，亦沒有苦味之口感，顯示苦味產生與氰酸之累積具有相關性。此外，總酚類化合物、總游離胺基酸、及可溶性性蛋白質甜龍筍較綠竹筍低。中文摘要 ii
Summary iii
壹、前言 1
貳、前人研究 2
一、竹筍概述 2
二、食用竹筍苦味 3
三、竹筍營養價值 4
參、材料與方法 5
一、 材料 5
(一) 第一次試驗 5
(二) 第二次試驗 5
二、 竹筍外觀與色澤 5
三、 出青與未出青竹筍之品質分析 6
(一) 多酚氧化酶活性、過氧化酶活性及氰酸 6
(二) 總酚類化合物、游離胺基酸、可溶性蛋白質及酪胺酸 6
(三) 總可溶性固形物 7
四、 煮沸處理對竹筍品質之影響 8
(一) 官能品評 8
五、 統計分析 8
肆、試驗結果 10
一、竹筍不同部位與出青與否氰酸含量差異 10
二、夏季常見食用筍出青與否之官能品評與品質調查 14
伍、討論 20
一、食用筍出青與否之官能品評與不同部位與出青與否氰酸含量差異 20
二、夏季常見食用筍品質調查 21
參考文獻 22
附錄 2
