淀粉多层级结构对面条煮后硬度品质形成机理的研究

Hardness is important for the eating qualities of cooked noodles, which will significantly affect the consumer acceptance. Starch, as the main component of wheat flour, can affect the hardness of cooked noodles through its interaction with water, gelatinization and retrogradation. Its interaction with water, gelatinization and retrogradation are controlled by the multi-level starch structure, which are the molecular, crystalline, and granular structure. This study aims to establish a starch structure-hardness relationship. Starches with different molecular, crystalline and granular structure are obtained through the separation of starch from different wheat varieties, adding pregelatinized/damaged starch, sieving through settlement with adding potato starch. Starch noodles with different structures processed using low-temperature extrusion, are treated as references to investigate the structure-cooked noodle hardness relationship. Reconstituted noodles are also made through low-temperature extrusion and noodle sheeting, to confirm the above established structure-cooked noodle hardness relationship. The molecular, crystalline and granular structure of cooked noodles, starch gelatinization, and retrogradation behavior are characterized using gel permeation chromatography, differential scanning calorimetry, Fourier Transform Infrared Spectrometer, X ray diffraction, mastersizer, and scanning electron microscopy. Water status of raw noodles with different structures is analyzed by low-field NMR. Those results are combined to understand the noodle hardness formation mechanism for cooked noodles with different starch structures. This understanding will provide theoretical and technical guidance for precisely controlling of the wheat processing in the view of starch structure and built a theoretical basis to obtain high-quality noodle wheat varieties through wheat breeding.

硬度是熟面条的重要质量要素，影响消费者对面条的接受程度。淀粉作为小麦面粉的主要组分，其与水的相互作用、糊化和老化都会影响面条硬度。而淀粉与水的作用、糊化和老化受淀粉分子、结晶和颗粒结构等多层级结构的影响。分离不同小麦品种中淀粉、添加小麦预糊化/破损淀粉、沉降法筛分小麦淀粉结合添加马铃薯淀粉的方法可获得具有不同分子、结晶、颗粒结构的淀粉，本项目以低温挤压的纯淀粉面条为对照研究淀粉分子、结晶、颗粒结构和煮后面条硬度的关系，以挤压（轧面）制作淀粉与谷朊粉重组面条，验证淀粉多层级结构和面条煮后硬度的关系。采用凝胶渗透色谱、差示扫描量热仪、傅里叶变换红外光谱仪、X射线衍射仪、粒度分析仪和扫描电镜等分析淀粉及面条煮后不同层级结构的变化，确证淀粉糊化和老化的程度。结合低场核磁共振技术分析不同结构淀粉和水分的结合状态，阐明面条煮后硬度的形成机理，为小麦面条质量的精准调控和面条用小麦育种提供理论参考。

硬度是熟面条的重要质量要素，影响消费者对面条的接受程度。通过分离不同小麦品种中淀粉、添加小麦预糊化淀粉、风选法筛分小麦淀粉的方法可获得具有不同分子、结晶、颗粒结构的淀粉，进而与谷朊粉进行复配研究淀粉分子、结晶、颗粒结构和煮后面条硬度的关系。研究发现小麦淀粉直链淀粉含量与面条硬度呈显著正相关，而精细结构也会影响面条硬度；淀粉结晶含量显著影响面条贮存硬度，且淀粉老化形成的结晶含量与面条硬度上升值呈显著正相关；淀粉颗粒粒度和小颗粒淀粉含量对面条硬度影响显著。结合低场核磁共振技术和红外显微镜分析不同结构淀粉和水分的结合状态以及淀粉和蛋白在面条中的分布，阐明面条煮后硬度的形成机理。本项目通过从淀粉结构角度揭示淀粉对面制品品质形成的重要性，是蛋白质对面制品品质影响研究的重要补充。为从淀粉角度进行面条用小麦育种的设计提供重要参考，也为从配粉角度生产高品质面条或稳定品质面条提供技术支持。发表SCI论文7篇，中文科技核心1篇，申请专利1项，参加国际会议3次、国内会议5次均做口头报告，达到项目申请时的预期目标。