【作者】 武俊超；

【导师】 高群玉；

【作者基本信息】 华南理工大学 ， 制糖工程， 2012， 硕士

【摘要】 通过采用酶法（脱支酶解处理）、物理法（湿热处理）、化学法（交联处理）及复合变性法（湿热协同交联处理）对豌豆淀粉进行处理后制备出系列抗性淀粉样品。采用偏光显微镜、扫描电镜（SEM）、差示扫描量热仪（DSC）、X-射线衍射仪、红外光谱仪、Brabender粘度仪和In vitro体外消化模型对抗性淀粉的颗粒形貌、热力学性质、结晶结构、粘度性质和体外消化性质进行了深入研究并分析对比了不同处理方法制备豌豆抗性淀粉的优劣。（1）采用脱支酶解处理制备豌豆抗性淀粉，结果表明，豌豆淀粉在普鲁兰酶添加量为300ASPU/g，脱支时间12h，凝沉时间24h后抗性淀粉含量最高为52.66%，脱支酶解处理后豌豆淀粉变成了不规则的碎片；溶解度和膨胀度均随着抗性淀粉含量的增加而逐渐降低；处理后豌豆淀粉的晶型由原来的C型变为B+V型，相对结晶度先升高后降低；糊化温度和糊化焓高于原淀粉，糊化温度先升高后降低；脱支酶解后的豌豆淀粉的Brabender粘度值急剧降低，高度酶解样品的粘度值几乎为零，崩解值和回升值均低于原淀粉；In vitro体外消化测定表明处理后样品消化产物量随着抗性淀粉含量升高而降低，3h后其消化产物量趋于稳定。（2）采用湿热处理制备豌豆抗性淀粉，主要研究了湿热水分、反应温度、反应时间对抗性淀粉含量的影响。当湿热水分为35%，130℃处理12h时其抗性淀粉含量达到最大值26.36%。扫描电镜结果表明湿热处理后豌豆淀粉的仍保持颗粒形状，但是在高温下表面水汽侵蚀，产生裂痕，部分颗粒表面受到破坏，偏光显微镜研究表明湿热处理后淀粉的偏光十字中心强度减弱；湿热处理后豌豆淀粉的晶型均由原来的C型变为A型，其相对结晶度增加5.26%～16.16%；随温度的升高豌豆淀粉的溶解度和膨胀度均增加，随着抗性淀粉含量的升高，其溶胀度均出现先增加再降低的趋势；湿热处理后豌豆淀粉的糊化温度均有所升高，糊化焓降低。（3）采用交联处理制备豌豆抗性淀粉，主要研究了交联剂用量、交联时间、交联温度对抗性淀粉含量的影响。当交联剂用量为12%，交联温度为45℃，交联时间为4h时其抗性淀粉含量最高为63.63%。控制合适的交联pH、交联温度和交联时间能够在交联剂用量为12%（占淀粉干基量）时的磷含量为0.38%；偏光显微镜显示交联处理后的淀粉的颗粒形貌并未发生显著变化，少许淀粉颗粒发生聚集，颗粒中心十字强度减弱；交联处理之后的豌豆淀粉的溶解度和膨胀度均显著降低，且随着抗性淀粉含量的升高其溶胀度均逐渐降低；交联处理之后的淀粉的晶型未发生变化，仍然为C型，但其结晶度增加；交联处理之后豌豆淀粉的Brabender粘度值急剧降低，且随抗性淀粉含量的升高其粘度值逐渐降低，高度交联淀粉样品的Brabender粘度值几乎为零；交联淀粉的糊化温度高于原淀粉，糊化焓值略有降低；交联淀粉在3456cm^-1处的特征峰消失，2948cm^-1处的特征峰增强，1392cm^-1处的特征峰强度明显减弱。（4）采用湿热协同交联制备抗性淀粉，并比较了四种不同处理方式制备抗性淀粉的优劣。湿热协同交联处理后制备抗性淀粉含量最高为68.96%；SEM结果表明湿热协同交联处理之后，豌豆淀粉的颗粒结构被破坏，出现部分碎片，部分颗粒之间粘连、堆积，其颗粒表面在高温下出现凹坑等；湿热协同交联淀粉的糊化温度有所升高，糊化焓值略有降低；湿热协同交联处理后的淀粉的晶型未发生改变，仍为C型，但其晶型有朝A型转变的趋势，结晶度提高。四种处理方式对豌豆淀粉的影响不一致，但是均能在一定程度上提高豌豆抗性淀粉的含量。更多还原

【Abstract】 In this study, pea starch was used as raw material, and subjected to enzymaticdebranching, heat-moisture treatment, cross-linking and cross-linking combined withheat-moisture treatment to obtain a resistant starch-rich powder with functional characteristics.Furthermore, the morphology, thermal property, crystallinity, viscosity and digestion ofresistant starch were characterized by polarizing microscope, SEM, DSC, XRD, Viscographand In vitro digestion techniques, respectively.Resistant starch was prepared by enzymatic debranching. The samples were cooled downand stored for12h after debranching treatment using300ASPU/g pullulanase for12h, theyield of RS reached52.66%. The granular structure of the resultant pea starch was completelydestroyed. The solubility and swelling power of samples decreased with the increase of RS.The native C-type starch was converted into typical B+V type pattern. The relativecrystallinity of samples increased initially, then decreased. Gelatinization temperatures andenthalpy of gelatinization of RS products increased compared to native starch. The viscosityof RS samples declined dramatically. And viscosity of highly debranched samples dropped toaround zero. Moreover, the breakdown and setback values of all samples decreased comparedwith native starch. The In vitro digestion result indicated that the amount of digested productsdecreased with the increase of RS.Pea starch was subjected to heat-moisture treatments （HMT） to evaluate the influence ofmoisture content, treated temperature and time on RS formation. The result indicated that RScontent reached the peak at26.36%when the starch treated with the moisture content of35%at130℃for12h. Scanning electron microscopy （SEM） showed that the starch granulestructure did not substantially change, but some pores or cracks were detected. The polarizedlight microscopy of RS suggested that the apparent intensity of birefringence was lower thannative starch. The native C-type starch was converted into type A. The relative crystallinity ofsamples increased by5.26%-16.16%. The solubility and swelling power of samples increasedwith the increase of reaction temperature. And the swelling power rose at first, then droppedgradually with the increase of RS content. Gelatinization temperatures increased but enthalpyof gelatinization decreased in HMT starches. Using garden pea starch as the raw material, cross-linking technique was applied toobtain resistant starch. The experimental factors include the usage of cross-linking, reactiontime and temperature were investigated. The highest RS content （63.63%） was reached whenthe starch treated with12%at45℃for4h. When12%of cross-linking agent was used,products containing0.38%of phosphorus could be obtained by optimizingcross-linking pH, retraction temperature and time. The polarized light microscopy of RSsuggested that the apparent intensity of birefringence was lower than that of native starch. Thesolubility and swelling power of RS samples declined significantly with the increase of RS.Both the native and resistant starches showed C-type X-ray diffraction pattern. Relativecrystallinity increased after modification. The viscosity of RS samples declined dramatically.And viscosity of highly cross-linked samples dropped to around zero. The gelatinizationtemperatures of cross-linked starch increased, while enthalpy of gelatinization decreasedslightly compared to native starch. The FTIR spectra of cross-linked starch showed that theabsorption peak at3456cm^-1disappeared, the absorption band at2948cm^-1enhanced, whilethe absorption band at1392cm^-1declined.Cross-linking combined with heat-moisture treatment of garden pea starch was carried outfor obtaining resistant starch. In the optimum reaction condition, the achieved highest RScontent was68.96%. Scanning electron microscopy （SEM） showed that the starch granulestructure was disrupted, some starch granules adhered and piled up together, and there weresome pores or cracks exist. The gelatinization temperatures of RS samples increased, whileenthalpy of gelatinization decreased slightly compared to native starch. The X-ray diffractionpattern of resistant starches still exhibited C-type. However, there were some differences thatmight indicate the presence of A-type crystals. And Relative crystallinity increased aftermodification. Furthermore, the advantages and disadvantages of the four methods werestudied. The four techniques mentioned above were turned out to be effective in preparingresistant starch and different aspects of garden pea starch were affected to some extent aftermodification process.更多还原