不同干燥方法对桑叶蛋白理化性质及营养特性的影响  

Effects of Different Drying Methods on the Physicochemical Properties and Nutritional Properties of Mulberry Leaf Proteins

作　　者：梁吉虹 俞燕芳 邓泽元[1] 张兵[1] LIANG Ji-hong;YU Yan-fang;DENG Ze-yuan;ZHANG Bing(State Key Laboratory of Food Science and Technology,Nanchang University,Nanchang 330047,Jiangxi,China;Economic Crops Research Institute of Jiangxi Province,Nanchang 330202,Jiangxi,China)

机构地区：[1]南昌大学食品科学与技术国家重点实验室,江西南昌330047 [2]江西省经济作物研究所,江西南昌330202

出　　处：《食品研究与开发》2023年第12期1-10,共10页Food Research and Development

基　　金：国家自然科学基金项目(32160539);江西省产业技术体系建设专项(JXARS-23)。

摘　　要：采用不同处理方式干燥桑叶后,提取桑叶蛋白,测定桑叶蛋白提取物的理化性质、营养特性并对其进行结构表征,以评价不同干燥方法对桑叶蛋白的影响。结果表明:经不同方式干燥后的桑叶蛋白提取物基本化学成分含量差异较大,其中冷冻干燥桑叶蛋白提取物蛋白含量最高,为68.89%;氨基酸组成无较大差异,第一限制性氨基酸为蛋氨酸+半胱氨酸;热风烘干桑叶蛋白提取物消化率最高,达到66.41%;由新鲜桑叶和冻干桑叶提取的蛋白表达情况一致,主要由一条约52 kDa分子量的蛋白条带组成,而烘干桑叶蛋白提取物蛋白电泳条带表达显著减弱;新鲜桑叶蛋白提取物的微观表面平整致密,热风烘干桑叶蛋白提取物和冷冻干燥桑叶蛋白提取物的表面粗糙多孔,使其与油、水的接触面积增加,有利于提高蛋白的溶解性。结果表明,不同干燥方式对桑叶蛋白的组成成分、功能和结构性质存在重要影响,真空冷冻干燥方式对蛋白特性的保存更为有利。After mulberry leaves were dried with different methods,proteins were extracted.The physicochemical properties,nutritional properties and structural characterization of mulberry leaf proteins extracted were determined to evaluate the effects of different drying methods on them.The results revealed that the basic chemical components in the protein extracts of mulberry leaves after drying by different methods was significantly different,and freeze-dried mulberry leaves had the most proteins(68.89%).There was no significant difference in amino acid composition,and the first limiting amino acid was methionine+cysteine.The digestibility of hot airdried mulberry leaf proteins was the highest,reaching 66.41%.The protein expression of fresh mulberry leaves and freeze-dried mulberry leaves was consistent,mainly composed of protein bands of about 52 kDa,while the protein band of hot air-dried mulberry leaves by electrophoresis was markedly weakened.The microscopic surface of fresh mulberry leaf proteins was flat and dense,while that of hot air-dried and freeze-dried mulberry leaf protein extracts was rough and porous,which increased their contact with oil and water and was conducive to improving the solubility of the proteins.It was found that the drying methods had an important effect on the composition,function and structural properties of mulberry leaf proteins,and vacuum freeze drying was more favorable for the preservation of protein properties.

关 键 词：桑叶 冷冻干燥 热风干燥 蛋白质 结构特性 

分 类 号：TS201.21[轻工技术与工程—食品科学]