摘要:本課題是以紫薯為原料，以料水比、乳酸菌接種量、發(fā)酵溫度為單因素做實(shí)驗(yàn)，以紫薯酸度、營養(yǎng)特性和抗氧化活性的變化為指標(biāo)，進(jìn)而通過正交試驗(yàn)得出乳酸菌發(fā)酵紫薯的最優(yōu)方案：料水比為1:3，接種量為6%，發(fā)酵溫度為40℃。在最優(yōu)方案條件下，測定乳酸菌發(fā)酵過程中紫薯總糖、游離氨基酸、可溶性蛋白、花青素、羥基自由基清除能力的變化，以探究紫薯在發(fā)酵期間營養(yǎng)特性和抗氧化活性的變化規(guī)律。實(shí)驗(yàn)結(jié)果顯示：最優(yōu)方案條件下，經(jīng)過14h的發(fā)酵，總糖含量從154.34 mg/mL明顯降低到 14.68mg/mL，游離氨基酸、可溶性蛋白和花青素含量均先升后降，與未發(fā)酵相比，游離氨基酸含量由15.55ug/mL下降到 8.69ug/mL，可溶性蛋白含量略有上升，從1.235%上升到1.474%，花青素含量從0.936 ug/mL下降到0.606 ug/mL；羥基自由基的清除率從55.00%上升到83.33%，紫薯抗氧化活性得到了提高。

關(guān)鍵詞 紫薯；乳酸菌發(fā)酵；營養(yǎng)特性；抗氧化活性

Abstract:This topic is based on purple potato as raw material, with the ratio of material to water, quantity of lactic acid bacteria, fermentation temperature as three single factor for experiment, with purple potato acidity, nutritional characteristics, and the change of antioxidant activity as an index, and through the orthogonal experiment of lactic acid bacteria fermentation purple potato optimal solution: material to water ratio of 1:3, inoculation quantity is 6%, the fermentation temperature of 40 ℃. Under the condition of the optimal scheme, determination of purple potato in lactic acid bacteria fermentation, total sugar, free amino acid, soluble protein, anthocyanins, hydroxyl radical scavenging ability of change, in order to explore the purple potato nutritional characteristics, change rule of antioxidant activity during the fermentation. Experimental results showed that: under the condition of the optimal solution, after 14h fermentation, from 154.34 mg/mL total sugar content significantly decreased to 14.68 mg/mL, free amino acid, anthocyanins and soluble protein content are rising before fall, compared with unleavened, free amino acid content by 15.55μg/mL, down to 8.69μg/mL, soluble protein content increased slightly, from 1.235% to 1.474%, the anthocyanins content in decreased from 0.936μg/mL to 0.606μg/mL. The hydroxyl free radical clearance rate increased from 55.00% to 83.33%, the fermentation could improve the antioxidant activity of purple potato.

Keywords  Purple potato  Lactic acid bacteria fermentation  Property  Antioxidant activity