艾草和鼠麴草萃取物抗氧化特性之研究

草仔粿是台灣傳統節慶小吃，因台灣各地區使用材料的差異而有不同稱呼，較常見的為使用艾草製作的艾草粿及鼠麴草製作的鼠麴粿。艾草(Artemisia argyi)為菊科蒿屬多年生草本植物，分布於亞洲及歐洲地區；鼠麴草(Gnaphalium affine)是菊科鼠麴草屬植物，分布在亞洲、中南半島、印度等地，多生長在低海拔野地，目前尚未有人工大量栽培。目前對艾草與鼠麴草的研究並不多，因此本研究進行艾草葉、鼠麴葉及鼠麴花的成分分析，並比較其水萃取物的抗氧化、抗醣化作用與酚類化合物含量，以了解艾草與鼠麴草之機能特性，進一步添加0.5~2.0% 艾草葉、鼠麴葉、鼠麴花及鼠麴花葉(1：1)粉末至糯米糰中製成粿皮，探討艾草與鼠麴草對米粿品質之影響。在一般成分方面，新鮮艾草葉、鼠麴葉及鼠麴花水分含量分別為84.1、86.5與77.2%，而在固形物中主要以粗纖維與可溶性無氮物為主，粗蛋白質只佔5.5、4.3與3.8%。比較樣品水萃取物對自由基之清除能力，結果顯示艾草葉、鼠麴葉及鼠麴花清除ABTS+自由基的IC50為244.1、212.3和191.0 µg/ml，清除DPPH自由基的IC50為166.2、84.0和107.8 µg/ml，顯示鼠麴葉與鼠麴花的抗氧化效果優於艾草葉。在抗醣化作用上亦有相同趨勢。在酚類分析上則發現艾草葉、鼠麴葉及鼠麴花總酚含量為158.3、175.8和214.3 mg/g，類黃酮化合物含量則為57.7、68.7和60.5 mg/g，仍以鼠麴葉與鼠麴花含量較多。添加艾草葉、鼠麴葉及鼠麴花製成草粿，物理特性分析結果顯示草粿色澤會隨著不同樣品及不同添加量而使L值與b值降低，添加鼠麴葉與艾草業者則會使草粿為綠色而使a值呈現負值。在物理特性測定中，隨著不同樣品及不同添加量增加硬度隨著上升，咀嚼性下降，彈性，黏性不受樣品添加而改變。在添加艾草葉、鼠麴葉及鼠麴花製成草粿感官品評試驗中，消費者對於添加艾草及鼠麴草製成之草仔粿的整體喜好排序為鼠麴葉粿、鼠麴花葉粿 > 鼠麴花粿 > 艾草粿，而外觀、風味、口感、餘味都呈現相似的趨勢，從選擇適合項目法中可推測出受到消費者喜歡的感官特性，在經群集分析可以得知各群集對草粿的喜好程度。

關鍵字

艾草；鼠麴草；草仔粿；抗氧化；質地分析

並列摘要

Taiwanese herbal rice cake is a very traditional homestyle snack or light meal. Herbal rice cake is a salty chewy snack consisting of radish slices and minced pork as the inner portion and glutinous rice and herb as the outer part. The most common use of herbs for rice cake are Artemisia argyi and Gnaphalium affine. Artemisia argyi, commonly known as Chinese mugwort, is a herbaceous perennial plant of Artemisia genus. It is native to China, Korea, Japan, and the Russian Far East. Gnaphalium affine, also known as Jersey cudweed, is a species of plants belonging to the genus Gnaphalium. The species grows extensively in East Asia including temperate regions of China, Korea, Japan, and Taiwan. The objectives of this study were to investigate the antioxidant and antiglycative capacities of water extracts from Artemisia argyi leaves (AAL), Gnaphalium affine leaves (GAL) and Gnaphalium affine flower (GAF), and to incorporate herbal powder (AAL, GAL, GAF and GAFL powder) into rice cakes at three different levels (0.5 1 and 2%) and to analyze its impact on the physicochemical properties and sensory characteristics of rice cakes. The results show that the moisture content of fresh AAL, GAL and GAF were 84.1, 86.5 and 77.2%, respectively. The main components in solids are crude fiber and soluble nitrogen-free extract. AAL, GAL and GAF all exhibited high antioxidant activity. GAL and GAF showed stronger scavenging effects on ABTS radicals and DPPH radicals than that of AAL. The IC50 were 244.1, 212.3 and 191.0 μg / ml for AAL, GAL and GAF on ABTS + free radicals, and 166.2 and 84.0 And 107.8 μg/ml on DPPH radicals, respectively. GAF exhibited the best scavenging effects on ABTS radicals and nitric oxide in all three samples. However, the inhibition of GAL against DPPH radicals was better than that of GAF and AAL. A higher content of total phenolics was observed in GAF comparison with GAL and AAL. The total phenolic content of AAL, GAL and GAF were 158.3,175.8 and 214.3 mg/g, respectively. There are more than 25% flavonoids in the extracted phenolic substances. The flavonoid contents were 57.7, 68.7 and 60.5 mg/g for AAL, GAL and GAF, respectively, Lightness (L-value) and yellowness (b value) of herbal rice cakes decreased as herbal powder content increased. The hardness and the chewiness were also decreased with increasing the herbal powder, Adhesiveness, Springiness is not affected by the sample added to change. In sensory evaluation test, the consumer preferences for herbal rice cakes were in the trend of GALGAFL> GAF > AAL that added to the general preferences. The incorporation of herbal powder reduced the appearance, flavor, taste and aftertaste aroma, aftertaste, flavor and appearance, and showed a similar trend of consumer preferences. The results in the present study showed that the high content of phenolic compounds and strong antioxidant activity in water extracts make Gnaphalium affine and Artemisia argyi the potential important novel natural antioxidant sources for the functional food and dietary supplement markets. Moreover, this study suggested the rice cakes with Gnaphalium affine were more acceptable than that of Artemisia argyi in terms of physicochemical and sensory properties.