【作者】 王海；

【导师】 屠康；

【作者基本信息】 南京农业大学 ， 农产品加工与贮藏， 2007， 硕士

【摘要】 荸荠是一种具有特殊质构特性、高淀粉含量、药食兼用的果蔬类食物。针对荸荠的特性比较研究了煮制过程中荸荠和马铃薯质构的不同变化、灌制过程中质构的变化及其与淀粉特性的关系，针对荸荠的加工现状，研究了荸荠加工废弃物中抑菌物质的抑菌活性及其应用。1．煮制是最简单，也是最普遍的受热过程。试验比较研究了煮制过程中荸荠和马铃薯质构性质的变化情况，结果表明，荸荠和马铃薯质构中弹性性质(脆度、硬度和黏着性)和塑性性质(凝聚性和回复性)受热后有不同的变化。荸荠的弹性性质总体上都是呈下降趋势，马铃薯除黏着性有个回复的过程，其他的两项指标均成下降趋势。荸荠的塑性性质随受热时间呈单向的变化；凝聚性随受热时间的增加而减小，回复性随受热时间的增加而增加；马铃薯的所有塑性性质都有回复的过程，凝聚性和回复性都是先减小后增加。TPA各参数相关性分析结果表明，荸荠和马铃薯各参数的相关性不同；荸荠的煮制过程是失水的，马铃薯则是吸水的，这一差别可能是荸荠质构热稳定性的一个重要原因。2．罐制是荸荠的一种重要加工方式，试验研究罐制加工中预煮、排气和杀菌三个受热过程荸荠质构的变化，结果表明，荸荠质构中弹性性质(脆度、硬度和粘着性)和塑性性质(凝聚性和回复性)对受热后有不同的变化，弹性性质参数值在排气过程中有所回升，塑性性质参数值则在整个过程中全部呈下降趋势；水分含量与粘着性呈极显著的负相关，与凝聚性和回复性呈显著正相关。同时对荸荠质构变化与淀粉特性的相关性做了分析，探讨通过改变淀粉特性以达到较好质构的可行性。研究发现荸荠淀粉的膨胀力、淀粉凝胶质构和淀粉RVA(快速粘度分析)谱特征值与荸荠的各项质构参数的相关性均达到显著和极显著水平。可根据荸荠质构特性的变化规律来控制不同的受热过程，尤其是预煮，从而得到具有较好质构的产品。另外，改变淀粉特性也可改善产品质构。3．从荸荠加工废弃物中提取抑菌物质，研究其抑菌活性及其应用，结果表明，荸荠英提取物对大肠杆菌、金黄色葡萄球菌、藤黄微球菌、枯草芽孢杆菌四种菌均有抑制作用，其中对金黄色葡萄球菌的抑制作用最强，且具持续性好。荸荠英提取物对大肠杆菌、金黄色葡萄球菌、藤黄微球菌的抑制作用高于1％的山梨酸钾溶液，而对枯草芽孢杆菌的抑制作用与其比较接近；利用荸荠英提取物能有效的防治彩色水果番茄贮藏过程根霉和链格孢引起的腐烂，与根霉相比，莘荠英提取物对链格孢抑制效果更好。更多还原

【Abstract】 Chinese water chestnut (Eleocharis dulcis) is a kind of food which has special texture characteristics, high starch content and medical effects. The texture changes of Chinese water chestnuts during cooking and canning, as well as the antibacterial activity and application of puchiin extracting from the processed wastes of Chinese water chestnuts were investigated in the thesis.1. Cooking is the simplest and most common heating process. The thesis compared the texture changes of Chinese water chestnuts with those of potatoes during the cooking process. The results indicated that elastic nature (Fracturability, Hardness and Adhesiveness) and plastic nature (Cohesiveness and Resilience) of Chinese water chestnuts and potatoes have different responses to thermal processing. The elastic properties of Chinese water chestnuts and potatoes decreased during the cooking process, while the Adhesiveness of potatoes increased at the initial period. The plastic properties of Chinese water chestnuts assumed that the unidirectional change along with the heating time. With the increase of heating time, the cohesiveness decreased, while the resilience increased. The cohesiveness and resilience of potatoes increased after the initial decreasing. The correlation analyses of TPA parameters indicated that the correlation of parameters of Chinese water chestnuts and potatoes are different. The Chinese water chestnuts are dehydrating during the cooking process, however potatoes are absorbent. This difference may be an important reason for the texture thermal stability of Chinese water chestnuts.2. The texture changes of Chinese water chestnuts (Eleocharis dulcis) during canning and the relationship between texture and water content were studied through different processing periods. The texture parameters of Chinese water chestnuts were analyzed during pre-cooking, evaporation and sterilization, respectively. The results showed that elastic nature (Fracturability, Hardness and Adhesiveness) and plastic nature (Cohesiveness and Resilience) of Chinese water chestnuts have different responses to thermal processing. The elastic properties increased during evaporation processing. However, the plastic properties decreased during the whole processing. In the meanwhile, water content showed significant negative correlation with Adhesiveness, and correlated positively with all plastic parameters. The relationship between changes of Chinese water chestnuts texture and starch properties was analyzed to find the feasibility of good product texture by changing starch properties. It was observed that swell power and gel properties were significantly correlated with different texture parameters. The conclusion is that it is possible to obtain good product texture through controlling different thermal processing, especially pre-cooking, or by changing starch properties.3. The antibacterial activity and application of puchiin extracting from the processed wastes of Chinese water chestnut were studied. The results showed that puchiin has inhibition activity to the bacteria Escherichia coli, Staphylococcus aureus, Micrococcus luteus and Bacillus subtilis. Among the four bacteria, the inhibition activity to S. aureus was the highest. The inhibition activity was better than 1% potassium sorbate solution on E. coli, S. aureus and M. luteus except B. subtilis. Puchiin could effectively control the spoilage caused by Rhizopus nigrican and Alternaria alternate on Lycopersic on esculentum var.cevasiforme. However, the inhibition activity to A. alternata is better than that of R. nigrican.更多还原