【作者】 王岩；

【导师】 乔旭光；

【作者基本信息】 山东农业大学 ， 食品科学， 2006， 硕士

【摘要】 大蒜（Allium Sativum L.）为百合科葱属植物。蒜的鳞茎具有极高的营养价值,含有蛋白质、糖类、脂肪、维生素和钙、磷、铁、硒、锗等矿物元素。另外,大蒜及其制品还有很高的药用价值,有杀菌、防止动脉粥样硬化和血小板凝集、防止血栓的形成、抗糖尿病、提高机体的免疫能力等多方面的作用。我国是大蒜的主要生产国,其产量占世界总产量的四分之一。除鲜食外,大蒜还经常加工成蒜泥、蒜汁、脱水蒜片、蒜粉等制品,但在加工过程中常常出现绿变现象,严重的影响了产品的外观质量,成为妨碍大蒜进一步加工的主要问题。因此研究大蒜制品绿变的机理,对有效控制发绿现象,达到规模化生产具有重要意义。本实验以大蒜鳞茎为原料,采用浸提法,选取适宜的提取溶剂,最大量的提取大蒜绿色素;通过薄层层析、液相色谱法对绿色素进行分离,为制备色素纯品奠定基础;并进一步研究了大蒜绿色素的稳定性,为大蒜绿色素的结构鉴定提供了理论依据。1.大蒜绿色素的提取试验首先通过浸提试验筛选最适宜的溶剂及其浓度,确定用80%的甲醇水溶液做浸提溶剂;通过L₉（3⁴）正交表进行三因素三水平试验,结果表明大蒜绿变物质浸提的最佳条件是:80%（V/V）甲醇溶液,按料液比1:3（g/mL）,室温浸提24h。2.大蒜绿色素的分离试验首先采用耗时短,用量少的薄层层析对大蒜绿色素进行分离,结果确定展层剂的配比为含77%（V/V）甲醇,3%（V/V）乙酸乙酯,0.24%（V/V）HCl的水溶液,可达到初步分离的目的;为了对色素进行结构鉴定,在薄板层析的基础上,采用高效液相色谱法对色素进一步分离,确定色谱条件为:ODS C₁₈色谱柱、流动相为pH=6的缓冲盐溶液（NaHPO₄和KH₂PO₄配制而成）:甲醇:乙睛=70:15:15,检测波长为430nm,流速0.8mL/min,色素被分离。3.大蒜绿色素性质的研究采用测定吸光值以及紫外可见光扫描的方法,研究了各种因素对色素稳定性的影响,试验结果表明,大蒜绿色素在酸性条件下比在碱性条件下稳定,在20℃以下稳定性最好,光的耐受性较差,Na₂SO₃对色素影响极大、Vc和H2O2对色素影响不大。7种金属离子中,Fe³⁺、Fe²⁺、Cu²⁺对色素都有一定的破坏作用,而K⁺、Ca²更多还原

【Abstract】 Garlic(Allium Sativum L.)is a kind of liliaceous plant. The bulb of garlic is rich in nourishment including protein, saccharide, fat, vitamin and mineral element such as Ca、P、Fe、Se、Ge and so on. Garlic have distinct effect of pharmacology, include bactericidal action, avoiding atherosclerosis, preventing forming thrombus, preventing diabetes and make the immunity of the body enhanced. The yield of garlic in China is 25 percent of the whole world and garlic is often made into different kinds of products, but garlic usually becomes green in the manufacture of puree and has bad effect on character.The methods of extraction and properties of garlic greening pigment were studied in this paper and the results were as follows:1. Extraction of the green pigment The result showed that 80%(V/V) methyl alcohol was the best solvent for the extraction of green pigment. According to the result of L9(34) orthogonal experiment, the best conditions of extraction were: the solvent was 80%(V/V) methyl alcohol, the ratio between material and solvent was 1:3(g/mL) and the extraction time was 24h respectively.2. Isolation of the green pigment The pigment could be preliminarily isolated used TLC method. The solvent of TLC was water solution including 77%(V/V) methyl alcohol, 3%(V/V)ethyl acetate and 0.24%(V/V) hydrochloric acid. In order to identify the structure of the green pigment, further isolation was done by HPLC method on the basic of TLC. The pigment was isolated into three parts under the conditions of ODS C18 column, moving phase of buffer salt solvent(pH=6), methyl alcohol and acetonitrile (with the rate of 70:15:15, V/V/V), detecting wavelength 430nm, 0.8mL/min of flow velocity.3. Properties of the green pigment The effect of different factors on the property of the green pigment was studied used UV-visible spectrophotometric methods. The result showed that the green pigment was更多还原