【作者】 钟秋平；

【导师】 谢碧霞；

【作者基本信息】 中南林业科技大学 ， 森林培育， 2007， 博士

【摘要】 随着社会的进步、经济的发展、人们生活水平的提高,传统种植的粮食作物已越来越不能满足国民的需要,人们追求食物的绿色、营养、保健,这些都促使我国的食品行业要进一步开发利用野生食物资源。野生淀粉植物种类繁多,蕴藏量大,分布广泛,开发利用价值极高,因此挖掘天然植物资源,势在必行,也成为了一种新潮流。橡实是最大的木本粮食资源,近几十年来,橡实的食用价值引起植物学家的兴趣,一些科研单位和生产管理部门对橡实种质资源分布、加工利用做了一些研究。国外有植物学家曾预言,橡实将成为未来的“粮食作物”和天然保健食品。本研究以4种野生橡实淀粉为材料,采用多因素控制对橡实淀粉进行高压处理、超微粉碎处理、湿热处理,系统研究高压处理、超微粉碎处理、湿热处理以及各因素对橡实淀粉加工特性影响变化规律,为开发利用这一丰富野生淀粉资源提供理论依据。采用X-衍射仪、Brookfield DV-II+粘度计、TA-XT2i质构仪等先进设备测定处理后淀粉的晶体特性、粘度、凝胶等特性,用采方差分析、回归拟合、响应面分析、灰色系统理论评价等方法进行科学系统分析,得到如下主要结论：(1)高压处理对橡实淀粉的晶体特性、粘度特性、流变特性、溶解特性、透光率、酶解率、回生特性、凝胶特性、凝沉特性有极显著影响。高压处理时淀粉的含水率对橡实的粘度、流变特性的剪切应力、溶解特性的膨润力、回生率、凝胶体的粘结性的影响呈正相关关系,即其值随高压处理时的含水率增加而增加,而对淀粉晶体结晶度、溶解特性的溶解度、酶解率、凝胶体的硬度、脆性、粘合性、咀嚼性的影响正好相反。高压处理时淀粉的含水率对透光率的影响呈山峰形,含水率55%是透光率的峰值。而对凝沉率的影响正好相反。高压处理的压力大小对淀粉流变特性的剪切应力、淀粉凝胶体的粘结性的影响呈正相关关系,即其值大小随压力加大而增加；而淀粉的结晶度、回生率的影响正好相反。高压处理的压力大小对淀粉的溶解度、酶解率、粉凝胶体回复性的影响曲线呈马鞍形,压力在150-350 MPa之间是其鞍部的峰值。而对淀粉的粘度特性、流变特性的剪切应力、溶解特性的膨润力、透光率、凝胶体的脆性、凝沉率的影响正好相反,呈凹槽形。高压处理需水分参与下经一定压力时间积累实现淀粉变性,在一定条件下压力不足时可以通过增加保压时间来补偿。(2)超微粉碎处理在一定时间内,不会改变淀粉的晶体类型,超过这一极限淀粉晶体就会转化成非晶体状态。淀粉的溶解特性、酶解率、淀粉凝胶体的硬度、粘合性、咀嚼性、回复性随超微时间延长而升高,而淀粉的晶体晶粒大小、结晶度、淀粉粘度、剪切应力、淀粉透光率、回生特性、淀粉凝胶体的粘结性则随超微时间延长而降低。用淀粉粒径大小表示对超微粉碎淀粉特性的影响,可降低超微时间表示函数的级次,即由用超微时间表示的生长函数降为用淀粉粒径大小表示的线性函数。(3)湿热处理能改变淀粉的晶体特性、粘度特性、流变特性、溶解特性、透光率、酶解率、回生特性、凝胶特性、凝沉特性。湿热处理的含水率、温度、处理时间对淀粉综合影响力的顺序为：含水率>处理时间>处理温度,即可得出湿热处理对橡实淀粉特性的影响是要在水的参与下,通过时间的积累来实现的。在湿热处理温度和处理时间一定时,橡实淀粉的结晶度、粘度、溶解度、酶解率和淀粉凝胶体的硬度、脆性、粘附性、弹性、粘合性、咀嚼性、回复性、粘结性随湿热处理时的含水率的增加而降低；橡实淀粉的流变剪切应力、膨润力、透光率、回生特性等表现则正好相反。在湿热处理的含水率和处理时间一定时,橡实淀粉的结晶度、粘度、剪切应力、膨润力、酶解率和淀粉凝胶体的弹性、回复性与湿热处理的温度呈负相关关系。而淀粉的溶解度、透光率、回生特性、凝沉特性则呈正相关关系。淀粉凝胶体的硬度、脆性、粘附性、粘合性、咀嚼性与处理温度呈抛物线关系,处理温度100℃是其峰值。在湿热处理的含水率和处理温度一定时,橡实淀粉的剪切应力、溶解度、膨润力、酶解率与处理的时间呈负相关关系。而淀粉的结晶度、粘度、透光率、回生特性则呈正相关关系。淀粉凝胶体的硬度、脆性、粘附性、粘合性、咀嚼性、回复性与处理时间呈抛物线关系,处理时间1h是其峰值。与目前淀粉研究比较,本研究有如下主要创新：(1)高压处理需水分参与下经一定压力时间积累实现淀粉变性,在一定条件下压力不足时可以通过增加保压时间来补偿,完善了高压处理淀粉的理论系统。(2)用淀粉粒径大小表示对超微粉碎淀粉特性的影响,可降低超微时间表示函数的级次,即由用超微时间表示的生长函数降为用淀粉粒径大小表示的线性函数。(3)湿热处理的含水率、温度、处理时间对淀粉综合影响力的顺序为：含水率>>处理时间处理温度。(4)提出了用粘度仪测定淀粉的回生特性的新方法。本文较为系统地研究三种物理方法对淀粉加工特性的影响,为淀粉的深加工提供了较丰富理论基础,但是在研究过程中作者认为在以下三个方面应进一步加强后续研究和思考：(1)由于高压处理会产生升温现象,建议在今后的高压处理研究中应考虑温度这一因素。(2)超微粉碎的载体等因素对淀粉特性有一定的影响,如果深入超微粉碎对淀粉加工特性时,应考虑载体因素。(3)淀粉热力特性是一个比较重要加工特性,建议加强这方面的研究。更多还原

【Abstract】 With the increasing of the society, economy and people’s life, the traditional crops can not be satisfied. And the food industry has to develop and utilize wild resources to satisfy people’s requirement to the food, which is non-pollution, nutrition and health. The wild starch plants have plenty varieties, vast numbers, common distribution, and excellent useful values. Therefore, it is necessary to develop natural plants resources, which is becoming modern fashion. The acorn is the largest woody crops resources. In recent several ten years, the botanists pay their attention to the edible value of the acorn, and some research and industry departments studied the distribution and process of the acorn resources. A foreign botanist predicted that the acorn would be the crops and natural healthy food in the future.The effects of high pressure treatment, micronization treatment, heat moisture treatment on the processing regularities of 4 kinds of wild acorn starches were studied, which provides the academic basis to develop them.The crystal properties, adhesiveness and gelling of the treated starches were measured by using X-ray diffraction, Brookfirld DV-II+ viscosimeter, and TA-XT2i texture analyzer. The key conclusions were summarized with variance analysis, regression fitting, response analysis and grey system theory evaluation.(1) The high pressure treatment effected on crystal properties, viscosity properties, rheological properties, Solubility properties, transparence, enzyme hydrolysis, retrogradation property, gelling and retrogradation property notably.With high pressure treatment, the effects of the moisture content on adhesiveness, shear stress, bentonite power, retrogradation and cohesiveness were positive skewed. In another words, their values increased with the increasing of the moisture content. And the effects of the moisture content on crystallinity, Solubility, enzyme hydrolysis, and hardness, fracturaturaility, gumminess and chewiness of the gell were opposite to the above ones. The effects of the moisture content on transmission showed as a slope, and the highest value showed up when the moisture content was 55%. And its effects on retrogradation were opposite. The effects of pressure on shear stress and gumminess were positive skewed, and their values increased with the pressure increasing. And the effects on crystallinity and retrogradation were opposite.The effects curve of the pressure on dissolution, enzyme hydrolysis and resilience of the powder gel showed as a saddle, and the highest value showed up when the pressure was 150～350 MPa. And its effects on adhesiveness, shear stress, bentonite power, transparence, fracturability and retrogradation were opposite, which was a fillister.The properties of starch changed with the condition of the moisture and proper time under high pressure. And it can be achieved by prolonging time if pressure is not big enough.(2) The crystal can not be changed only if the time of the micronization treatment is long enough. The solubility, enzyme hydrolysis, hardness, gumminess, chewiness and resilience increased with the prolonging treatment time, and the crystal size and rate, adhesiveness, shear stress, transparence, retrogradation and cohesiveness decreased with the prolonging treatment time.Using the diameter of the starch to indicate the effects of the micronization on the starch properties can decrease the times of the micronization time in a funtion. In another words, the function can become a linear one by using starch diameter instead of a growth function by using micronization time.(3) The heat moisture treatment can change crystal properties, viscosity properties, rheological properties, solubility properties, transparence, enzyme hydrolysis, retrogradation property, gelling and retrogradation property. The increased order of the effects of moisture content, temperature and treatment time on the starch was moisture content, time and temperature. The effects of the heat moisture treatment on the starch were achieved by the time accumulating participated by water.Under certain temperature and time, the crystal, viscosity, solubility, enzyme hudrolysis of the starch, and the hardness, fracturability, adhesiceness, springiness, gumminess, chewiness, resilience and cohesiveness of the gel decreased as the moisture contents increasing. And the reflection of the shear stress, bentonite power, transparence and retrogradation property were the opposite.Under certain temperature and time, the crystal, viscosity, shear stress, bentonite power, enzyme hydrolysis of the starch, and the springiness and resilience of the gel were appositive skewed with the temperature of the treatment. And the solubility, transparence, retrogradation and retrogradation property were positive skewed. The hardness, fracturability, adhesiveness, gumminess and chewiness showed a parabolic curve with the temperature, and the highest value showed up when the temperature was 100℃.Under certain moisture content and temperature, the shear stress, solubility, bentonite power and enzyme hydrolysis were appositive skewed with the treatment time. And the crystal, viscosity, transparence and retrogradation property were positive skewed. The hardness, fracturability, adhesiveness, gumminess, chewiness and retrogradation showed a parabolic curve with the treatment time, and the highest value showed up when the time was 1 h.The innovations in this study are as below:(1) The properties of starch changed with the condition of the moisture and proper time under high pressure. And it can be achieved by prolonging time if pressure is not big enough, which completed the theory system of treating starch with high pressure.(2) Using the diameter of the starch to indicate the effects of the micronization on the starch properties can decrease the times of the micronization time in a funtion. In another words, the function can become a linear one by using starch diameter instead of a growth function by using micronization time.(3) Under the heat moisture treatment, the increased order of the comprehensive effects of moisture content, temperature and treatment time on the starch was moisture content, time and temperature.(4) Using viscosimeter to measure the retrogradation property of the starch is put forward firstly.The effects of three kinds of physical methods on the process properties of the starches were studied systematically, which supplied plenty theory method for further process of the starches. However, three topics below should be continued:(1) The temperature will increase with the high pressure treatment, therefore, temperature should be noticed.(2) The carrier of micronization will influence the starch properties, and it should be noticed when further studying the starch process properties.(3) The heat properties of the starch is one of the important process properties, and it should be focused on.更多还原