Electroneutral Quaternization/Sulfosuccination for Alleviating the Adverse Effect of Paste Aging on the Properties of Corn Starch Film

For the purpose of alleviating the adverse effect of paste aging on the properties of corn starch film, a series of electroneutrally quaternized/sulfosuccinylated starches（EQSS） with different degrees of substitution（DS） were synthesized via the quaternization/sulfosuccination of acid-thinned corn starch（ATS） by varying the amounts of N-（3-chloro-2-hydroxypropl） trimethylammonium chloride, maleic anhydride, and sodium hydrogen sulfite. The influence of paste aging on the properties of starch film cast from heat-induced starch paste was investigated and the properties were explored in terms of tensile strength, elongation, work at break, degree of crystallinity, and flex-fatigue resistance. The experimental results showed that the paste ageing generated adverse influence on the elongation, work at break, and flex-fatigue resistance of starch film. Further experiments showed that electroneutral quaternization/sulfosuccination of starch were able to alleviate the negative effect of paste ageing on the elongation, work at break, and flex-fatigue resistance, thereby obviously enhancing the elongation, work at break and flex-fatigue resistance, and thus reducing the drawback of brittleness. The enhancement depended on the amounts of the substituents introduced. With the increase in DS value, the elongation and work at break as well as flex-fatigue resistance continuously rose, whereas the tensile strength gradually reduced.

Anaerobic biodegradation,physical and structural properties of normal and high-amylose maize starch films

Biodegradable plastics have attracted considerable attention in recent years due to their biodegradability,biocompatibility and non-toxicity.In this study,normal maize starch(containing 25%amylose)and high-amylose maize starch(containing 80%amylose)were served as model materials to prepare starch/polyvinyl alcohol(PVA)blends.To comprehensively study the effects of amylose contents on the film performances,the mechanical properties,water resistance and anaerobic biodegradability of the two films were examined.Moreover,the processes of anaerobic degradation were investigated by evolutions of biogas production,pH in reactors and the changes of film structures and compositions.The results indicated that amylose content played an important role in the microstructures of starch film as well as mechanical properties and water resistance,whereas it had no significant influence on anaerobic biodegradability of the films.Nonetheless,the structure of high-amylose maize starch/PVA film was more suitable and beneficial to the anaerobic biodegradation than that of the normal maize starch/PVA film,because it could effectively avoid accumulation of volatile fatty acids,which contributed to the stable biogas production,short fermentation period and non-souring in the reactor.

Effect of Starch Dodecenylsuccinylation on the Adhesion and Film Properties of Dodecenylsuccinylated Starch for Polyester Warp Sizing

A series of dodecenylsuccinylated starches( DSSs) with different degree of substitution( DS) were prepared via the esterification of dodencenylsuccinic anhydride with hydrolyzed cornstarch in aqueous dispersion for investigating the influences of starch dodecenylsuccinylation upon the performances such as apparent viscosity and surface tension of starch paste, film behaviors,and adhesion to fibers for warp sizing. It was found that the dodecenylsuccinylation was able to reduce the surface tension of cooked starch paste and enhance the adhesion of starch to polyester fibers. It was also capable of depressing the brittleness of native starch and improving the mechanical behaviours such as breaking elongation and work-to-break of starch film. Initial increase in DS level of dodecenylsuccinylation enhanced these positive effects,while excessively increasing the level resulted in marked reduction in tensile strength of starch film and significant decrement in reaction efficiency. X-ray diffraction patterns of starch films showed the dodecenylsuccinates derivatized onto the backbones of starch depressed the degree of crystallinity of starch film. Based on the paste behaviors, adhesion, and film properties, the dodecenylsuccinylation level is recommended in a range of 0. 015-0. 025 for sizing polyester warps.

Influence of Phase Behavior and Miscibility on Mechanical, Thermal and Micro-Structure of Soluble Starch-Gelatin Thermoplastic Biodegradable Blend Films

Polymer blends of cold water soluble starches (amylose or amylopectin soluble starch) with gelatin were prepared using solvent casting method. The solid state miscibility and polymer-polymer interactions between the constituent polymers were studied by fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorirmetry (DSC), light optical microscopy (OP) and scanning electron microscopy (SEM), whereas the thermal stability of the blends was studied by thermogravimetric analysis (TGA). Furthermore, tensile and water vapor barrier properties of the blends were assessed. The obtained results exhibited that gelatin was more miscible with amylose soluble starch than with amylopectin soluble starch. Moreover, enhancing mechanical and water barrier properties of amylose soluble starch/gelatin blends were more pronounced than those of amylopectin soluble starch/gelatin blends. Generally, tensile strength (TS) and Elongation percentage (E) of the blend films were found to be gradually increased with increasing the proportion of gelatin. Nevertheless, increasing starch proportion was in favor of decreasing water vapor permeability (WVP). At equal proportions of starch and gelatin (1:1), TS was raised up to 8.69 MPa for amylose soluble starch/gelatin blend films while it raised up to 4.96 MPa for amylopectin soluble starch/gelatin blend films, and so on E was increased to its maximum by ~179.6% for soluble amylose starch/gelatin blends while it was increased to ~114.5% for amylopectin soluble starch/gelatin blends. On the other hand, WVP was significantly decreased to be 6.46 and 12.09 g·mm/m2·day·kPa for blends of amylose and amylopectin soluble?starches, respectively.

Structural and Thermomechanical Study of Plastic Films Made from Cassava-Starch Reinforced with Kaolin and Metakaolin

The structural and thermomechanical properties of starch-based plastic films reinforced with kaolin and metakaolin have been studied by various techniques (X-ray diffraction, IR-TF spectroscopy, scanning electron microscopy, tensile tests, and thermal resistance). The results obtained showed that kaolin, an inert material, prevents the starch from losing its granular structure and to solubilize during the heating, generating plastic films of low Young’s modulus (7 MPa). On the other hand, metakaolin, an amorphous and dehydroxylated material obtained after heating of kaolin at 700°C for 1 hour, substantially improves the thermomechanical properties of the plastic films. The Young’s modulus increases from 19 MPa to 25 MPa while the thermal resistance increases from 90°C to 120°C. This was attributed to good dispersion of the metakaolin in the polymer matrix after the loss of the granular structure of the starch during heating.

State of Knowledge on Starch as an Alternative Solution to Petrochemical Resources—A Review

The use of plastics from petrochemical resources poses environmental impacts, and one of the alternative solutions is the use of starch. The objective of this present work has been to present the literature on starch, and to highlight the debate in the development of composite films. The approach adopted was to present the state of the art on starch and thermoplastic starch matrix composites. The work shows that starch is available worldwide and can be used in the manufacture of biodegradable plastics;the debate remains on the reinforcement of thermoplastic starch to improve its physical and mechanical properties poor;then researchers must diversify the reinforcements to see the impact on the properties of thermoplastic starch.

科教融汇及思政育人新路径——食品包装技术课程创新实验设计

在前期研究基础上,为食品包装技术实验课开设了明胶-淀粉复合膜制备和性能评估实验,引入绿色包装材料最新科研成果,紧贴社会热点环境保护,结合食品专业多学科知识,涵盖产品研发全过程,全方位渗透思想政治教育。实验包括学生自行筛选复合膜配方、进行质量评估和数据分析、撰写论文模式实验报告。3年的教学实践表明,该课程设计创新性强、综合性高、学生认可度高且教学成果丰富,能极大激发学生实验兴趣和培养正确思想价值。

基于纤维素纳米晶乳化陈皮精油的淀粉基抗菌膜的制备与性能

以玉米淀粉(corn starch,CS)为基质、柠檬酸为交联剂、纤维素纳米晶(cellulose nanocrystals,CNC)乳化陈皮精油(orangepeelessentialoil,OPO)制备的Pickering乳液为抗菌剂,采用流延法成功制备了CS/CNC-OPO抗菌复合膜;探讨了CNC和OPO的添加量对CS/CNC-OPO抗菌复合膜的机械强度、水蒸气透过率、水接触角、抗菌性能等的影响,并采用傅里叶变换光谱、X射线衍射光谱和扫描电子显微镜对CS/CNC-OPO抗菌复合膜进行表征。结果表明,当OPO添加量为11%,CNC和OPO比例为1∶11(g/mL)时,CS/CNC-OPO膜的性能最好,水蒸气透过率为1.03×10^(-3)g/(m·h·kPa),水接触角为74.53°,拉伸强度达6.01 MPa,对大肠杆菌和金黄色葡萄球菌的抑菌面积高达88.4 mm2和96.45 mm^(2)。该淀粉基膜强度好,且具有较好的疏水和抗菌性,在食品包装领域具有广阔的应用前景。

Ag/TiO_(2)/Ag_(3)PO_(4)-LNCF/淀粉复合膜的制备与保鲜性能研究

为改善果蔬保鲜中的微生物侵染和乙烯催熟问题,采用原位沉淀和辐照法合成Ag/TiO_(2)/Ag_(3)PO_(4)(ATAP)三元异质结光催化剂,利用流延法制备ATAP-木质纳米纤维素(LCNF)/淀粉复合膜。探究ATAP负载条件、光催化剂类型对乙烯的吸附、分解性能,以及抑菌效果的影响。利用SEM观察复合薄膜的微观形貌,评估不同光催化薄膜对南瓜的保鲜效果。结果表明,适宜的ATAP掺杂量能使光催化剂均匀分散在淀粉膜基质中,从而提升其光催化性能;当ATAP外掺杂量为3%、内掺杂量为2%时,复合膜具有最佳的乙烯分解性能和抑菌效果,其分解率为7.73%,抑菌圈直径为11.46 mm。复合膜具有较好的南瓜保鲜作用,保鲜7 d后的南瓜表面与内部的霉菌覆盖面积显著降低,失重率减小至28.27%;复合膜对金黄色葡萄球菌和霉菌均具有显著的抑制效果,其菌落总数、金黄色葡萄球菌数和霉菌数分别为5.55×10~4,4.95×10~4,3.00×10~4 CFU/g,均优于其他材料及对照组。研究为果蔬保鲜新材料的开发提供理论参考。

含紫薯花青素的槟榔芋淀粉薄膜性能及其应用

开发含紫薯花青素(PSPA)并可生物降解的槟榔芋淀粉薄膜(TSF),并研究其光学性能、厚度、含水率、水溶性、颜色、总酚含量、抗氧化活性、红外光谱和微观结构等性能,初步探讨TSF对鲜切莴笋、鱼肉和猪肉储存过程中新鲜度的指示作用。研究表明TSF的紫外-可见光谱和PSPA溶液的光谱变化规律是一致的,表明PSPA与槟榔芋淀粉具有良好的成膜机制。TSF厚度适中,含水率为39.17%,水溶性为36.93%;TSF的DPPH清除率达到94%,表明TSF的抗氧化活性高。将TSF应用于鲜切莴笋、鱼肉和猪肉的新鲜度监测,TSF先呈现淡紫色,随着时间推移,鲜切莴笋、鱼肉和猪肉逐渐腐败变质,48 h后,TSF在莴笋中呈现蓝紫色、猪肉中呈现浅绿色、鱼肉中呈现淡黄色。

甲酸木质素纳米颗粒的制备及疏水性能研究

本研究以玉米秸秆、杨木及松木为原料,利用不同液比的甲酸与原料(1∶10,1∶9,1∶8和1∶7)制浆,从制浆黑液中分离得到甲酸木质素,进一步制得甲酸木质素纳米颗粒,探究了不同甲酸木质素的酚羟基含量差异。结果表明,3种原料甲酸木质素具有木质素的基本结构特征,液比1∶9时制得3种原料甲酸木质素酚羟基含量分别为2.69、2.82、3.09 mmol/g。水接触角实验结果表明,3种原料甲酸木质素压片具有较强的亲水性。将甲酸木质素纳米颗粒用于制备甲酸木质素纳米颗粒/淀粉复合膜,复合膜的水接触角显著增加,其疏水性能与甲酸木质素的原料种类和制浆液比有关。经4个月老化后,复合膜的疏水性能进一步增强,3种原料甲酸木质素纳米颗粒/淀粉复合膜的水接触角最高分别可达127.2°、125.1°和123.5°。研究结果对增强木质素的疏水性能及扩展疏水性膜材料的应用具有积极意义。

纤维素纳米纤丝/普鲁兰酶体系对淀粉膜性能的影响研究

本研究分析了纤维素纳米纤丝(CNF)/普鲁兰酶(Pul)体系对淀粉膜性能的影响。结果表明,CNF/Pul体系处理后的淀粉具有更高的短程有序性及更多的双螺旋结构,且淀粉晶型中出现了B型特征峰。CNF/Pul体系处理后得到的淀粉膜具有良好的表面均匀性和机械性能,该膜的拉伸强度从2.44 MPa(Nature-StF)增至7.32 MPa(CNF/Pul-StF),增加了2倍。光/水蒸气透过率测试结果表明,CNF/Pul体系处理后的淀粉膜具有更好的光学透过性,且对水蒸气阻隔性能有一定的增强作用。CNF/Pul体系处理后淀粉膜的光学透过率从49.3%~51.2%(Nature-StF)增至56.1%~60.1%(CNF/Pul-StF),且水蒸气透过系数从9.26×10^(−12)g·cm/(Pa·s·cm^(2))(Nature-StF)减至6.33×10^(−12)g·cm/(Pa·s·cm^(2))(CNF/Pul-StF)。

OSA改性高直链玉米淀粉复合疏水膜的制备及性能研究

选用辛烯基琥珀酸酐(OSA)对高直链玉米淀粉(HACS)进行酯化处理,制备了3种不同改性程度的OSA淀粉(OS⁃3、OS⁃6、OS⁃9)。以3种OSA淀粉为原料,明胶为复配大分子,制备了3种OSA改性高直链玉米淀粉复合膜(OS⁃3/GEL、OS⁃6/GEL、OS⁃9/GEL),考察了复合膜的透光性、水溶性、吸湿性、水蒸气透过率及表面疏水性。结果表明,相比原淀粉复合膜,OSA改性高直链玉米淀粉复合膜各项性能均得到改善。其中OS⁃6/GEL的性能表现最佳,透光率达到87.72%,水溶性下降了24.5%,吸湿性下降了29.6%,水蒸气透过率下降了30.35%,表面最大静态接触角达到124.6°,动态接触角在3 min后仍达到100°以上;OSA改性降低了原淀粉的结晶度,提高了成膜组分间的相容性;OSA基团的引入使得淀粉与明胶分子中羟基作用减弱,二者间产生更为强烈的氢键作用。OSA改性改善了原淀粉复合膜的疏水性能,适量OSA基团引入制备得到的OS⁃6/GEL性能最佳,成膜表现出优异的疏水性能。

ε-聚赖氨酸盐酸盐接枝淀粉薄膜的制备及性质研究

目的对淀粉接枝抑菌肽,得到抑菌淀粉,并挤出成膜,表征其性质,为淀粉的应用提供参考。方法借助偶联剂,将ε-聚赖氨酸盐酸盐(ε-polylysine-HCl,ε-PLH)接枝到玉米淀粉上,分析其化学结构、微观结构、热性能及抑菌性。通过熔融挤出法将接枝淀粉与聚乳酸(Polylactic acid,PLA)、聚己二酸/对苯二甲酸丁二酯(Poly butyleneadipate-co-terephthalate,PBAT)共混改性成膜,表征其力学性能、抑菌性能。结果FTIR显示,ε-PLH被成功接枝到淀粉分子上;热重分析(TGA)结果显示,接枝淀粉的起始分解温度有所下降;含有30%接枝淀粉的PBAT/PLA薄膜具有更高的拉伸强度。此外,接枝淀粉添加量为30%的薄膜对大肠杆菌、金黄色葡萄球菌的抑制率分别达到了46.53%、68.81%。结论接枝ε-聚赖氨酸盐酸盐是一种有效的淀粉改性途径,接枝淀粉/PBAT/PLA薄膜具有良好的应用前景。

淀粉醛强化大豆分离蛋白/槲皮素复合膜制备及性能研究

目的探究淀粉醛(dialdehyde starch,DAS)对大豆分离蛋白(soy protein isolate,SPI)/槲皮素(quercetin,QR)复合膜特性的影响。方法以青稞淀粉为原料,通过高碘酸钠氧化制备了DAS,以SPI为基质,以DAS和QR为添加物,以拉伸强度、水分阻隔性能、抗氧化性能为指标进行单因素试验,通过响应面优化试验筛选出DAS强化的SPI/QR复合膜最佳制备条件后,对复合膜的微观结构进行表征,并对其物理学性能进行测试。结果DAS强化的SPI/QR复合膜最佳制备条件为每100 mL蒸馏水中添加SPI 6.00 g、pH为8、DAS 5%、QR 4%、DES 25%(DAS、QR、DES以SPI质量计)。在此条件下,薄膜的拉伸强度为(7.37±0.39)MPa、水蒸气透过系数为(3.54±0.29)×10^(-11)g/(m·s·Pa)、抗氧化活性为(70.88±0.40)%。结构表征结果表明,DAS的添加使得该复合膜分子间形成了共价亚胺键,表面结构及横断面结构更加致密。此外,该复合膜具有较好的热稳定性、紫外阻隔性、疏水性。结论DAS处理改善了SPI/DAS/QR复合膜的内部结构,提高了复合膜的拉伸、耐水、抗氧化性能、热稳定、紫外阻隔、疏水性能。本研究可为基于SPI可生物降解薄膜的开发及应用提供参考。

基于甜菜红素的pH指示膜性能研究

以甜菜红素为指示剂,木薯淀粉、花生壳纤维素为成膜基材,采用流延法制备pH指示膜,对指示膜进行性能表征,并分析不同甜菜红色素含量对指示膜热稳定性、机械性能、光学性能、含水量、水溶性以及pH敏感性的影响。通过红外光谱及扫描电镜分析发现甜菜红素与成膜基质相容性良好,各基团交联稳定。结果表明,40%(质量分数)的甜菜红素提高了指示膜的热稳定性能、紫外光阻隔性、断裂伸长率和水润胀率(33.54%至45.94%),降低了指示膜的含水率(15.33%至13.00%)和拉伸强度(7.69 MPa至2.22 MPa),熔点从105℃升至125℃。指示膜表现出良好的pH敏感性,在酸性环境下呈暗红色,中性时呈酒红色,碱性时呈黄色/紫色,色差均大于5,肉眼可视。表明甜菜红素pH指示膜具有广阔的开发前景。

壬酸增塑改性明胶膜的制备及性能研究

可生物降解塑料的研发对于实现“双碳”目标具有重要的意义和价值。以明胶为原材料,通过壬酸增塑、双醛淀粉交联和热压处理相结合的方法制得明胶膜,探究壬酸增塑和热压处理对双醛淀粉交联的明胶膜结构和性能的影响。结果表明,当壬酸添加比例为20%时,改性的明胶膜表面光滑、结构致密,具有最高的抗张强度和较低的断裂伸长率、水蒸气透过率和溶胀性能。经过11 min的热压处理后,明胶膜表现出良好的耐水性和力学性能,且在土壤中被降解22 d后仍然能够维持较完整的薄膜形貌,降解34 d后其质量损失超80%。基于壬酸增塑、双醛淀粉交联和热压处理制备的明胶膜机械强度高、耐水性好且可生物降解,其为环境友好蛋白塑料的研发提供了有益策略。

淀粉-多酚复合膜的研究进展:从功能特性到食品包装应用

塑料包装污染是全球性的环境问题,因此开发生物可降解材料已成为食品包装领域的研究热点。淀粉是自然界中常见的多糖,具有价格低廉、安全无毒和易加工等优势,在环境友好型的食品包装材料开发中表现出较大潜力。然而,纯淀粉膜的阻隔性能较差、功能特性单一,无法满足人们对食品贮存期和新鲜程度逐步升高的要求。多酚是具有多种保健作用的天然抗氧化剂,因此可将不同类型的多酚引入到淀粉基薄膜中制成具有多种功能特性的淀粉-多酚复合膜。本文以挤出成型、静电纺丝和溶剂浇铸3种制备方法为主,综述淀粉-多酚复合膜的制备流程、影响因素和方法的优缺点,阐释淀粉与多酚的相互作用,分析添加多酚对淀粉基复合膜物化性能的影响以及在食品包装领域的应用,并对未来淀粉-多酚复合膜的发展与挑战进行展望。

热塑性淀粉基薄膜研究进展

淀粉是由α-葡萄糖分子聚合而成的天然高分子材料,来源广泛,主要分布在植物的根茎中,具有价格低廉、可再生及可生物降解等优点。利用淀粉制备天然可降解塑料薄膜,对解决和改善环境污染有着重大意义。与淀粉基材料相比,聚乙烯、聚丙烯、聚苯乙烯等合成高分子为原料制成的热塑性产品具有气味刺激性、不可生物降解和污染环境等缺点。基于淀粉的天然优势,以淀粉为原料制成的可生物降解热塑性材料成为国内外研究人员的研究热点。主要综述了淀粉的结构和性质,淀粉的增塑方法,淀粉膜的制备方法,热塑性淀粉基功能性膜材料研究进展,并对热塑性淀粉基功能材料的研究内容进行了总结与展望。