本文主要研究内容
作者李丹丹（2019）在《感应电场辅助多糖酸解及其作用机制探究》一文中研究指出：酸解可提高多糖利用率并改善其理化性质,通常用作酶法和化学改性的前处理手段。但多糖结构的复杂性和部分多糖水溶性差等问题,导致其酸解存在效率低、反应时间长和产品降解程度低等现象。电场处理可缩短有机化学反应时间、提高产品得率。目前电场技术在多糖加工中的应用集中于辅助不导电介质中多糖的自组装,并有研究证明电场可辅助多糖在导电介质中的改性,但电场辅助多糖改性的作用机制尚不明确。且现有电加工技术包括脉冲电场和欧姆加热均需使用金属电极,存在电极电化学反应污染产品的隐患。感应电场是由本研究中心根据磁电诱导原理构建的无电极电加工技术,在食品加工领域有着较大的应用潜力。因此,本文首先从电场中多糖运动方向角度探索感应电场对多糖酸解的影响,其次从提高带电粒子运动速率出发改善多糖酸解效率,最后通过分析感应电场中粒子的运动模式,解析感应电场辅助多糖酸解的作用机制。具体研究内容和结果如下:感应电场产生热效应和非热效应以促进多糖的酸解,热效应占主导作用,而非热效应与多糖带电性相关。利用高效尺寸排阻色谱联合多角度激光和示差双检测器系统（HPSEC-MALLS-RI）测定加感应电场和不加电场酸解过程中不同带电性多糖分子量的变化,并监控酸解液温度的变化。结果表明,电场可产生热效应以促进酸解,与多糖带电性无关。电场辅助酸解过程中,酸解液温度先上升后维持稳定。相应地,多糖分子量先迅速降低后缓慢下降。如,感应电场辅助酸解过程中,瓜尔胶酸解液温度从24.5℃快速上升至42℃后（4 h）缓慢升高至43℃（24 h）,其分子量在前4 h迅速从17.23×105g/mol降低到4.728×105g/mol后缓慢下降至1.357×105 g/mol（24 h）;与不加电场相比,75 V感应电场辅助酸解24 h后,瓜尔胶分子量降低了15.423×105 g/mol。非热效应可促进带负电多糖和不带电多糖的酸解,但对带正电多糖的酸解有轻微抑制作用。控制温度一致时（消除热效应的影响）,与水浴加热相比,75 V感应电场辅助酸解24 h后,带负电多糖马铃薯淀粉酸解液中还原糖含量增加了20.8%,不带电多糖瓜尔胶分子量降低了25.89%,而带正电多糖壳聚糖分子量却增加了6%。介质导电性是决定感应电场辅助多糖酸解效率的关键因素。电场对不导电介质中的酸解反应无辅助作用,但对导电介质中的酸解反应有促进作用,且电导率越高,酸解速率越快。以不导电的甲醇、乙醇、异丙醇和正丁醇为酸解反应介质,利用HPSEC-MALLS-RI测定加电场和不加电场处理过程中瓜尔胶分子量的变化发现,加感应电场时瓜尔胶的醇酸降解速率常数与不加电场时接近。当以导电介质水为媒介时,随加盐量的增加,热效应增强,电导率显著增加,而阻抗(ZS和Zload)明显降低,从而系统输出功率Pouti=（?）,n=1,2,3…增加。随KCl添加量从0增加到6 wt%,电场辅助瓜尔胶酸解反应速率常数从2.739×10-91/（h·g·mol）增加到3.417×10-9 1/（h·g·mol）。采用红外光谱、核磁氢谱、扫描电镜、X-射线衍射分析感应电场辅助酸解对瓜尔胶结构的影响发现,瓜尔胶甘露糖和半乳糖的比例未发生明显变化,没有新的官能团形成;颗粒结构被完全破坏成小的片段;结晶结构未发生显著变化。热重分析结果说明其热稳定性略有下降。流变分析表明瓜尔胶溶液的剪切黏度显著降低（P<0.05）。感应电参数显著改变电场辅助多糖酸解效率（P<0.05）。激励电压和反应器串联个数增加,系统输入功率Pin i=（?）,n=1,2,3…增加,从而电场辅助多糖酸解速率显著增加（P<0.05）。随反应器个数从1增加到4,马铃薯淀粉酸解液中还原糖含量从0.46 g/L增加到5.28 g/L;当激励电压从15 V增加到75 V时,还原糖含量从0.59 g/L增加到5.28g/L（60 h）。另外,加盐量增加,感应电场辅助马铃薯淀粉酸解的效率也增加,进一步证明介质电导率与感应电场辅助多糖酸解效率相关。利用扫描电镜、X-射线衍射仪、激光粒度分析仪和HPSEC-MALLS-RI研究感应电场辅助酸解过程中淀粉颗粒结构、结晶结构和链结构的变化发现,感应电场辅助淀粉酸解的过程包括三个步骤:首先,淀粉颗粒表面变粗糙,外部结晶硬层被破坏,分子量降低;然后,淀粉内部的无定形区和结晶区被同时水解,但无定形区水解速率更快;最后,颗粒内部由支链淀粉紧密排列形成的结晶区被继续水解,颗粒尺寸和分子量缓慢下降。与原淀粉相比,酸解淀粉的溶解度增加,而膨胀力和淀粉糊黏度显著降低。多糖带电量对感应电场辅助酸解效率的影响不显著。本论文以乙酰化修饰制备的不同带电量（脱乙酰度）壳聚糖为研究对象,通过HPSEC-MALLS-RI测定溶解态（0.15mol/L HCl）和不溶态（1.5 mol/L HCl）壳聚糖在感应电场辅助酸解过程中的分子量变化。结果表明,脱乙酰度的增加虽然提高了感应电加工系统输出功率,但影响不明显,从而电场作用下溶解态壳聚糖酸解效率随脱乙酰度变化不显著。X-射线衍射仪和扫描电镜分析表明乙酰化过程破坏了壳聚糖的颗粒结构和结晶结构,使其更容易被氢离子攻击,从而有利于酸解。因此,不溶态壳聚糖在电场中的酸解效率随脱乙酰度的增加反而略有降低。由于壳聚糖和盐竞争水分,通过加盐来研究介质电导率对感应电场辅助溶解态壳聚糖酸解难以实现,但其酸解效率随激励电压和反应器个数的增加而增加。酸解后壳聚糖结构和理化性质的变化采用红外光谱、核磁氢谱、扫描电镜、X-射线衍射、流变和热重进行分析,结果表明壳聚糖脱乙酰度略有变化,结晶结构和颗粒结构被部分破坏,结构致密性降低,其乙酸溶液的黏度显著降低,热稳定性略有下降。感应电场辅助多糖酸解的作用机制是改变带电粒子运动方向和运动速率,产生热效应和非热效应以改变多糖酸解效率。运动方向取决于电场方向和粒子带电性。感应电场是呈周期性变化的交变电场,带电粒子在其中做变速往复运动。多糖带电性不同,在电场中运动方向不同,其与氢离子的碰撞几率存在差异,产生的非热效应不同:带负电多糖运动方向与氢离子相反,碰撞几率增加,非热效应促进该类多糖酸解;电场对中性多糖的影响可忽略,但带正电的氢离子做快速往复运动,碰撞几率增加;带正电多糖和氢离子均沿电场方向运动,碰撞几率降低,非热效应抑制此类多糖酸解。运动速率与感应电压和粒子带电量相关。感应电压和多糖带电量越大,单位时间内粒子运动路径更长,产生的热效应越强,但多糖带电量的影响不显著。反应器个数、激励电压值和介质电导率的增加均可显著提高感应电压值。热效应在感应电场加工过程中起主导作用,非热效应的影响次之,因此感应电场对带正电、不带电和带负电多糖的酸解均有促进作用。
Abstract
suan jie ke di gao duo tang li yong lv bing gai shan ji li hua xing zhi ,tong chang yong zuo mei fa he hua xue gai xing de qian chu li shou duan 。dan duo tang jie gou de fu za xing he bu fen duo tang shui rong xing cha deng wen ti ,dao zhi ji suan jie cun zai xiao lv di 、fan ying shi jian chang he chan pin jiang jie cheng du di deng xian xiang 。dian chang chu li ke su duan you ji hua xue fan ying shi jian 、di gao chan pin de lv 。mu qian dian chang ji shu zai duo tang jia gong zhong de ying yong ji zhong yu fu zhu bu dao dian jie zhi zhong duo tang de zi zu zhuang ,bing you yan jiu zheng ming dian chang ke fu zhu duo tang zai dao dian jie zhi zhong de gai xing ,dan dian chang fu zhu duo tang gai xing de zuo yong ji zhi shang bu ming que 。ju xian you dian jia gong ji shu bao gua mai chong dian chang he ou mu jia re jun xu shi yong jin shu dian ji ,cun zai dian ji dian hua xue fan ying wu ran chan pin de yin huan 。gan ying dian chang shi you ben yan jiu zhong xin gen ju ci dian you dao yuan li gou jian de mo dian ji dian jia gong ji shu ,zai shi pin jia gong ling yu you zhao jiao da de ying yong qian li 。yin ci ,ben wen shou xian cong dian chang zhong duo tang yun dong fang xiang jiao du tan suo gan ying dian chang dui duo tang suan jie de ying xiang ,ji ci cong di gao dai dian li zi yun dong su lv chu fa gai shan duo tang suan jie xiao lv ,zui hou tong guo fen xi gan ying dian chang zhong li zi de yun dong mo shi ,jie xi gan ying dian chang fu zhu duo tang suan jie de zuo yong ji zhi 。ju ti yan jiu nei rong he jie guo ru xia :gan ying dian chang chan sheng re xiao ying he fei re xiao ying yi cu jin duo tang de suan jie ,re xiao ying zhan zhu dao zuo yong ,er fei re xiao ying yu duo tang dai dian xing xiang guan 。li yong gao xiao che cun pai zu se pu lian ge duo jiao du ji guang he shi cha shuang jian ce qi ji tong （HPSEC-MALLS-RI）ce ding jia gan ying dian chang he bu jia dian chang suan jie guo cheng zhong bu tong dai dian xing duo tang fen zi liang de bian hua ,bing jian kong suan jie ye wen du de bian hua 。jie guo biao ming ,dian chang ke chan sheng re xiao ying yi cu jin suan jie ,yu duo tang dai dian xing mo guan 。dian chang fu zhu suan jie guo cheng zhong ,suan jie ye wen du xian shang sheng hou wei chi wen ding 。xiang ying de ,duo tang fen zi liang xian xun su jiang di hou huan man xia jiang 。ru ,gan ying dian chang fu zhu suan jie guo cheng zhong ,gua er jiao suan jie ye wen du cong 24.5℃kuai su shang sheng zhi 42℃hou （4 h）huan man sheng gao zhi 43℃（24 h）,ji fen zi liang zai qian 4 hxun su cong 17.23×105g/moljiang di dao 4.728×105g/molhou huan man xia jiang zhi 1.357×105 g/mol（24 h）;yu bu jia dian chang xiang bi ,75 Vgan ying dian chang fu zhu suan jie 24 hhou ,gua er jiao fen zi liang jiang di le 15.423×105 g/mol。fei re xiao ying ke cu jin dai fu dian duo tang he bu dai dian duo tang de suan jie ,dan dui dai zheng dian duo tang de suan jie you qing wei yi zhi zuo yong 。kong zhi wen du yi zhi shi （xiao chu re xiao ying de ying xiang ）,yu shui yu jia re xiang bi ,75 Vgan ying dian chang fu zhu suan jie 24 hhou ,dai fu dian duo tang ma ling shu dian fen suan jie ye zhong hai yuan tang han liang zeng jia le 20.8%,bu dai dian duo tang gua er jiao fen zi liang jiang di le 25.89%,er dai zheng dian duo tang ke ju tang fen zi liang que zeng jia le 6%。jie zhi dao dian xing shi jue ding gan ying dian chang fu zhu duo tang suan jie xiao lv de guan jian yin su 。dian chang dui bu dao dian jie zhi zhong de suan jie fan ying mo fu zhu zuo yong ,dan dui dao dian jie zhi zhong de suan jie fan ying you cu jin zuo yong ,ju dian dao lv yue gao ,suan jie su lv yue kuai 。yi bu dao dian de jia chun 、yi chun 、yi bing chun he zheng ding chun wei suan jie fan ying jie zhi ,li yong HPSEC-MALLS-RIce ding jia dian chang he bu jia dian chang chu li guo cheng zhong gua er jiao fen zi liang de bian hua fa xian ,jia gan ying dian chang shi gua er jiao de chun suan jiang jie su lv chang shu yu bu jia dian chang shi jie jin 。dang yi dao dian jie zhi shui wei mei jie shi ,sui jia yan liang de zeng jia ,re xiao ying zeng jiang ,dian dao lv xian zhe zeng jia ,er zu kang (ZShe Zload)ming xian jiang di ,cong er ji tong shu chu gong lv Pouti=（?）,n=1,2,3…zeng jia 。sui KCltian jia liang cong 0zeng jia dao 6 wt%,dian chang fu zhu gua er jiao suan jie fan ying su lv chang shu cong 2.739×10-91/（h·g·mol）zeng jia dao 3.417×10-9 1/（h·g·mol）。cai yong gong wai guang pu 、he ci qing pu 、sao miao dian jing 、X-she xian yan she fen xi gan ying dian chang fu zhu suan jie dui gua er jiao jie gou de ying xiang fa xian ,gua er jiao gan lou tang he ban ru tang de bi li wei fa sheng ming xian bian hua ,mei you xin de guan neng tuan xing cheng ;ke li jie gou bei wan quan po huai cheng xiao de pian duan ;jie jing jie gou wei fa sheng xian zhe bian hua 。re chong fen xi jie guo shui ming ji re wen ding xing lve you xia jiang 。liu bian fen xi biao ming gua er jiao rong ye de jian qie nian du xian zhe jiang di （P<0.05）。gan ying dian can shu xian zhe gai bian dian chang fu zhu duo tang suan jie xiao lv （P<0.05）。ji li dian ya he fan ying qi chuan lian ge shu zeng jia ,ji tong shu ru gong lv Pin i=（?）,n=1,2,3…zeng jia ,cong er dian chang fu zhu duo tang suan jie su lv xian zhe zeng jia （P<0.05）。sui fan ying qi ge shu cong 1zeng jia dao 4,ma ling shu dian fen suan jie ye zhong hai yuan tang han liang cong 0.46 g/Lzeng jia dao 5.28 g/L;dang ji li dian ya cong 15 Vzeng jia dao 75 Vshi ,hai yuan tang han liang cong 0.59 g/Lzeng jia dao 5.28g/L（60 h）。ling wai ,jia yan liang zeng jia ,gan ying dian chang fu zhu ma ling shu dian fen suan jie de xiao lv ye zeng jia ,jin yi bu zheng ming jie zhi dian dao lv yu gan ying dian chang fu zhu duo tang suan jie xiao lv xiang guan 。li yong sao miao dian jing 、X-she xian yan she yi 、ji guang li du fen xi yi he HPSEC-MALLS-RIyan jiu gan ying dian chang fu zhu suan jie guo cheng zhong dian fen ke li jie gou 、jie jing jie gou he lian jie gou de bian hua fa xian ,gan ying dian chang fu zhu dian fen suan jie de guo cheng bao gua san ge bu zhou :shou xian ,dian fen ke li biao mian bian cu cao ,wai bu jie jing ying ceng bei po huai ,fen zi liang jiang di ;ran hou ,dian fen nei bu de mo ding xing ou he jie jing ou bei tong shi shui jie ,dan mo ding xing ou shui jie su lv geng kuai ;zui hou ,ke li nei bu you zhi lian dian fen jin mi pai lie xing cheng de jie jing ou bei ji xu shui jie ,ke li che cun he fen zi liang huan man xia jiang 。yu yuan dian fen xiang bi ,suan jie dian fen de rong jie du zeng jia ,er peng zhang li he dian fen hu nian du xian zhe jiang di 。duo tang dai dian liang dui gan ying dian chang fu zhu suan jie xiao lv de ying xiang bu xian zhe 。ben lun wen yi yi xian hua xiu shi zhi bei de bu tong dai dian liang （tuo yi xian du ）ke ju tang wei yan jiu dui xiang ,tong guo HPSEC-MALLS-RIce ding rong jie tai （0.15mol/L HCl）he bu rong tai （1.5 mol/L HCl）ke ju tang zai gan ying dian chang fu zhu suan jie guo cheng zhong de fen zi liang bian hua 。jie guo biao ming ,tuo yi xian du de zeng jia sui ran di gao le gan ying dian jia gong ji tong shu chu gong lv ,dan ying xiang bu ming xian ,cong er dian chang zuo yong xia rong jie tai ke ju tang suan jie xiao lv sui tuo yi xian du bian hua bu xian zhe 。X-she xian yan she yi he sao miao dian jing fen xi biao ming yi xian hua guo cheng po huai le ke ju tang de ke li jie gou he jie jing jie gou ,shi ji geng rong yi bei qing li zi gong ji ,cong er you li yu suan jie 。yin ci ,bu rong tai ke ju tang zai dian chang zhong de suan jie xiao lv sui tuo yi xian du de zeng jia fan er lve you jiang di 。you yu ke ju tang he yan jing zheng shui fen ,tong guo jia yan lai yan jiu jie zhi dian dao lv dui gan ying dian chang fu zhu rong jie tai ke ju tang suan jie nan yi shi xian ,dan ji suan jie xiao lv sui ji li dian ya he fan ying qi ge shu de zeng jia er zeng jia 。suan jie hou ke ju tang jie gou he li hua xing zhi de bian hua cai yong gong wai guang pu 、he ci qing pu 、sao miao dian jing 、X-she xian yan she 、liu bian he re chong jin hang fen xi ,jie guo biao ming ke ju tang tuo yi xian du lve you bian hua ,jie jing jie gou he ke li jie gou bei bu fen po huai ,jie gou zhi mi xing jiang di ,ji yi suan rong ye de nian du xian zhe jiang di ,re wen ding xing lve you xia jiang 。gan ying dian chang fu zhu duo tang suan jie de zuo yong ji zhi shi gai bian dai dian li zi yun dong fang xiang he yun dong su lv ,chan sheng re xiao ying he fei re xiao ying yi gai bian duo tang suan jie xiao lv 。yun dong fang xiang qu jue yu dian chang fang xiang he li zi dai dian xing 。gan ying dian chang shi cheng zhou ji xing bian hua de jiao bian dian chang ,dai dian li zi zai ji zhong zuo bian su wang fu yun dong 。duo tang dai dian xing bu tong ,zai dian chang zhong yun dong fang xiang bu tong ,ji yu qing li zi de peng zhuang ji lv cun zai cha yi ,chan sheng de fei re xiao ying bu tong :dai fu dian duo tang yun dong fang xiang yu qing li zi xiang fan ,peng zhuang ji lv zeng jia ,fei re xiao ying cu jin gai lei duo tang suan jie ;dian chang dui zhong xing duo tang de ying xiang ke hu lve ,dan dai zheng dian de qing li zi zuo kuai su wang fu yun dong ,peng zhuang ji lv zeng jia ;dai zheng dian duo tang he qing li zi jun yan dian chang fang xiang yun dong ,peng zhuang ji lv jiang di ,fei re xiao ying yi zhi ci lei duo tang suan jie 。yun dong su lv yu gan ying dian ya he li zi dai dian liang xiang guan 。gan ying dian ya he duo tang dai dian liang yue da ,chan wei shi jian nei li zi yun dong lu jing geng chang ,chan sheng de re xiao ying yue jiang ,dan duo tang dai dian liang de ying xiang bu xian zhe 。fan ying qi ge shu 、ji li dian ya zhi he jie zhi dian dao lv de zeng jia jun ke xian zhe di gao gan ying dian ya zhi 。re xiao ying zai gan ying dian chang jia gong guo cheng zhong qi zhu dao zuo yong ,fei re xiao ying de ying xiang ci zhi ,yin ci gan ying dian chang dui dai zheng dian 、bu dai dian he dai fu dian duo tang de suan jie jun you cu jin zuo yong 。
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论文作者分别是来自江南大学的李丹丹，发表于刊物江南大学2019-03-18论文，是一篇关于感应电场论文,多糖酸解论文,运动方向论文,运动速率论文,作用机制论文,江南大学2019-03-18论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自江南大学2019-03-18论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：感应电场论文; 多糖酸解论文; 运动方向论文; 运动速率论文; 作用机制论文; 江南大学2019-03-18论文;