食品胶对甘薯淀粉膜机械及渗透性能的影响

本实验以抗张强度、断裂拉伸应变、透湿性和透氧性为指标,研究食品胶对甘薯淀粉膜性能的影响。结果表明,添加食品胶能够显著增加甘薯淀粉膜的抗张强度,当甘薯淀粉膜中羟丙基羧甲基纤维素(HPCMC)含量为5g/100g 淀粉时,其抗张强度达36.22MPa,是对照膜(25.93MPa)的1.4 倍。添加羧甲基纤维素钠(CMC-Na)和魔芋葡甘露聚糖(KGM)可显著增加甘薯淀粉膜的透湿性,其他食品胶对甘薯淀粉膜的透湿性影响不显著,同时不同浓度的HPCMC 对甘薯淀粉膜的透湿性的影响也不显著。添加HPCMC、黄原胶和壳聚糖(5g 胶体/100g 淀粉)能够显著增加甘薯淀粉膜的透氧性,添加KGM 能够显著降低淀粉膜的透氧性,CMC-Na 和甲基纤维素(MC)对透氧性影响不显著。高浓度HPCMC(＞ 7g/100g 淀粉)能够降低甘薯淀粉膜的透氧性。当HPCMC 含量为10g/100g 淀粉时,淀粉膜的透氧性降低至0.749 × 10-6cm3·m/(m2·d·kPa),比对照膜降低了67%。     

增塑剂对甘薯淀粉膜机械及渗透性能的影响

鉴于塑料食品包装带来的严重环境问题,研究可食、可降解的包装薄膜非常必要.本文以抗张强度、断裂伸长率、透湿性和透氧性为指标,研究增塑剂对甘薯淀粉膜性能的影响.结果表明,甘油和山梨醇的增塑效果优于聚乙二醇和蔗糖,使膜的断裂伸长率和透湿性更大,透氧性更小.甘油(浓度>5g/100g淀粉)可以显著降低甘薯淀粉膜的抗张强度,较高浓度甘油(浓度>10g/100g淀粉)可以显著改善甘薯淀粉膜的断裂伸长率.甘油的添加使甘薯淀粉膜的透湿性增加.较低浓度甘油(浓度≤7g/100g淀粉)的添加降低甘薯淀粉膜的透氧性,高浓度甘油(浓度>10g/100g淀粉)又使透氧性有所增加,但总体上用甘油增塑的淀粉膜的透氧性均比未增塑的对照膜的透氧性小.     

可食用萝卜渣包装膜的制备与性能研究

以白萝卜渣纤维为基材,通过加入成膜剂、增塑剂制得可食用包装膜,然后研究不同萝卜渣浓度、不同成膜剂添加量、不同增塑剂添加量,对膜的感官性状影响。同时对膜厚度、耐折、耐破、抗冲击、透气性、透湿性、拉伸强度等性能进行测试,分析测试数据后,结果表明:制备可食用萝卜渣包装膜的技术条件为去离子水400mL、白萝卜渣20g、卡拉胶添加量2.0%、甘油3.0mL、硬脂酸添加量0.5%时,膜的感官性状和机械性能为最佳。     

响应面法优化阿魏酸淀粉酯膜制备工艺

采用单因素试验和响应面法考察阿魏酸淀粉酯取代度、干燥温度和甘油添加量对阿魏酸淀粉酯膜抗张强度（tensile strength,TS）和断裂伸长率的影响。结果表明：随着取代度的增大,阿魏酸淀粉酯膜的TS逐渐增大,断裂伸长率逐渐减小;当干燥温度不大于60 ℃时,阿魏酸淀粉酯膜的TS随着温度的升高略微增大,当温度升高到60 ℃以上时,TS显著降低（P＜0.05）,阿魏酸淀粉酯膜的断裂伸长率随着温度的升高显著降低（P＜0.05）;随着甘油添加量的增大,阿魏酸淀粉酯膜的TS逐渐减小,断裂伸长率逐渐增大。综合考虑各因素对阿魏酸淀粉酯膜机械性能的影响,在取代度0.068、干燥温度40 ℃、甘油添加量1.20 g/4.0 g条件下制备阿魏酸淀粉酯膜,膜的TS较高,为10.23 MPa;在取代度0.023、干燥温度41 ℃、甘油添加量1.30 g/4.0 g条件下制膜,膜的断裂伸长率较高,为321.65%。     

无纺布-纳米纤维素PU合成革的制备与研究

以无纺布为基材,研究了Na OH溶液在80℃对基布的处理时间、醇性聚氨酯涂布量、纳米纤维素纤维的用量对基布透湿性的影响以及水性聚氨酯膜定量、甘油用量对合成革物理、机械性能的影响。结果表明Na OH溶液在80℃下处理基布1h、纳米纤维素纤维的用量为3%、醇性聚氨酯涂布量为130g/m2时基布的透湿性能最好;当水性聚氨酯膜涂布量为100g/m2、甘油用量为15%时合成革的透湿性能最佳,此时合成革的表观密度、抗张强度、断裂伸长率、崩裂强度较接近天然皮革。通过扫描电镜对基材和合成革表面皮纹的形貌进行表征并对合成革的透湿性能等性能进行检测。     

硫酸盐对玉米淀粉糊化性与成膜性影响

玉米淀粉糊化过程中,硫酸盐能够影响玉米淀粉糊化与成膜性能。分别添加亚硫酸钠、硫代硫酸钠0,0.05,0.1,0.2,0.4和0.8 g至5 g/100 mL淀粉悬液中,90℃糊化40 min,测定糊化性指标;添加同水平硫酸盐制备玉米淀粉-甘油-海藻酸钠复合膜,测定膜机械性能、透明度、水溶性,并用DSC,SEM检测膜热稳定性与形貌表征。结果表明:亚硫酸钠的添加使淀粉膨胀度由9.56(g/g)增加至15.53(g/g),溶解度由0.07(g/g)增加至0.45(g/g),凝沉性减弱,无水析出。硫代硫酸钠的添加未改变淀粉膨胀度,溶解度由0.07(g/g)增加至0.34(g/g),凝沉率由7%增加至12%。DSC分析表明:两种膜热稳定性好;SEM显示膜较粗糙,表面结晶减少。两种硫酸盐的添加使淀粉溶解性、透光率、吸水性及膜水溶性、断裂伸长率增加,膜透明度降低。     

增塑剂对玉米醇溶蛋白膜阻隔性能影响北大核心

玉米醇溶蛋白具有较好成膜性,但其形成膜较脆,需通过添加不同增塑剂加以改善;但添加增塑剂会使膜阻隔性能受到影响。该实验以甘油、聚乙二醇(PEG)400、单甘油酯为增塑剂,研究在不同乙醇浓度时制备玉米醇溶蛋白(zein)膜阻湿性及阻油性;结果表明,当乙醇浓度为80%、甘油添加量为0.3 g/g zein,PEG–400添加量为0.2 g/g zein,单甘油酯添加量为0.3 g/g zein时,膜的水蒸汽透过率最小,透油率最大。     

可食性绿豆淀粉膜制作工艺的研究

以绿豆淀粉为主要材料,甘油作为增塑剂,羧甲基纤维素(CMC)作为增强剂,以可食性膜厚度、抗拉强度、断裂延伸率、阻水性为指标,研究了甘油添加量、CMC添加量、干燥温度、干燥时间等因素对可食性淀粉膜性能的影响。结果表明以绿豆淀粉为成膜主体,配以0.4 g/g淀粉的甘油和0.06 g/g淀粉的CMC,在80℃烘干4 h,得到淀粉膜的抗拉强度为9.51 MPa,延伸率为114.55%,水滴渗透时间(Ts)为240.98 min/mm。     

纳米Fe~(3+)-TiO_2改性聚乙烯醇基紫胶复合涂膜材料工艺优化

以新型纳米Fe3+-TiO2、紫胶、琥珀酸单甘油酯(succinylated monoglycerides,SMG)添加量为影响因素,对乳化紫胶聚乙烯醇(polyvinyl alcohol,PVA)溶液体系改性,以成膜透湿率为指标,通过响应面试验方法优化复合膜制备工艺,并对复合膜抑菌性能进行研究。结果表明:紫胶协同纳米Fe3+-TiO2交联改性PVA能显著降低PVA基膜材料的透湿率(P0.05);复合膜中紫胶添加量与纳米Fe3+-TiO2及SMG添加量对成膜透湿率有显著的交互作用(P0.05);以复合膜透湿率为指标的回归优化结果:纳米Fe3+-TiO2添加量9.18 mg/100 m L、紫胶添加量1.33 g/100 m L、SMG添加量0.92 g/100 m L,此时成膜透湿率为(392.43±8.37)g/(m2·24 h),比PVA单膜降低了60%以上;复合膜在可见光催化反应180 min后,与PVA单膜相比,沙门氏菌和李斯特菌的活菌数量分别降低1.8(lg(CFU/m L))和1.6(lg(CFU/m L)),说明纳米Fe3+-TiO2改性PVA基紫胶复合涂膜材料能赋予其可见光催化靶向抑菌性能。     

壳聚糖木薯淀粉明胶复合可食抗菌保鲜膜性能的研究

研究了壳聚糖/木薯淀粉/明胶/甘油共混膜的机械性能、透湿性能、透气性能及共混涂膜的防腐保鲜效果。结果表明,木薯淀粉、明胶、甘油、木薯淀粉与明胶交互作用对共混膜的抗拉强度影响显著;对断裂伸长率影响显著的因素为木薯淀粉、明胶、甘油及其二次项、明胶与甘油的交互项;对共混膜透湿系数影响显著的主要因素是木薯淀粉、甘油、木薯淀粉与木薯淀粉之间的交互作用;木薯淀粉、明胶、木薯淀粉与木薯淀粉之间的交互作用对共混膜的透气系数影响也是显著的。此外,此共混涂膜具有一定的防腐作用。     

Mechanical properties of pea starch films associated with xanthan gum and glycerol

The aim of this study was to evaluate the effect of the addition of xanthan gum and glycerol to the starch of green pea with high content of AM (cv. Utrillo) in the preparation of films and their physical characteristics. Filmogenic solution (FS) with different levels of pea starch (3, 4, and 5%), xanthan gum (0, 0.05, and 0.1%), and glycerol (glycerol–starch ratio of 1:5 w/w) were studied. The FS was obtained by boiling (5 min), followed by autoclaving for 1 h at 120°C. The films were prepared by casting. Films prepared only with pea starch were mechanically resistant when compared to other films, prepared with corn, cassava, rice, and even other pea cultivars (yellow, commercial). The tensile strength of these films is comparable to synthetic films prepared with high‐density polyethylene and linear low‐density polyethylene. However, they are films of low elasticity when compared to other films, such as rice starch films, and especially when compared to polyethylene films. The increased concentration of starch in the solution increased the puncture force. The increased concentration of glycerol slightly decreased the film crystallinity and interfered in the mechanical properties of the films, causing reduction of the maximum values of tensile strength, strain at break, and puncture force. The plasticizer also caused an increase of elongation at break. Xanthan gum was important to formation of films; however, it did not affect their mechanical properties.     

Development of oxidised and heat-moisture treated potato starch film

This study investigated the effects of sodium hypochlorite oxidation and a heat-moisture treatment of potato starch on the physicochemical, pasting and textural properties of potato starches in addition to the water vapour permeability (WVP) and mechanical properties of potato starch films produced from these starches. The carbonyl contents, carboxyl contents, swelling power, solubility, pasting properties and gel texture of the native, oxidised and heat-moisture treated (HMT) starches were evaluated. The films made of native, oxidised and HMT starches were characterised by thickness, water solubility, colour, opacity, mechanical properties and WVP. The oxidised and HMT starches had lower viscosity and swelling power compared to the native starch. The films produced from oxidised potato starch had decreased solubility, elongation and WVP values in addition to increased tensile strength compared to the native starch films. The HMT starch increased the tensile strength and WVP of the starch films compared to the native starch.     

Modification of the properties of milk protein films by gamma radiation and polysaccharide addition

This study has demonstrated that gamma radiation induced an improvement of barrier properties and tensile strength of films containing calcium caseinate, whey protein isolate and glycerol (1:1:1) through creation of a crosslinked β‐structure. Up to 32 kGy the effect was accompanied by an increase in rigidity and was larger with increasing radiation dose. The irradiation of protein solutions also caused improvement of puncture strength of films prepared with potato starch, soluble potato starch or sodium alginate addition (at a level of 50 g kg^?1 of total proteins). Addition of potato starch did not influence mechanical properties of films but significantly improved barrier properties. Addition of sodium alginate resulted in improvement of both puncture strength and barrier properties. Addition of sodium alginate to irradiated protein solution resulted in films revealing the greatest improvement in properties. Gels prepared using irradiated protein solutions mixed with calcium salt were stronger than gels prepared using non‐irradiated solutions owing to the preferred binding of calcium ions to the crosslinked protein network. Presence of sodium alginate and potato starch weakened the interaction of proteins with calcium ions owing to entrapment of proteins in the polysaccharide network, while addition of soluble potato starch promoted these interactions. Copyright © 2006 Society of Chemical Industry     

四种多糖代替明矾改善红薯粉的品质特性

以阿拉伯胶、海藻酸钠、黄原胶、果胶四种天然多糖代替传统红薯粉生产中的明矾,研究了4种添加剂对红薯粉品质的影响。以添加剂种类为因素,添加剂量为水平,通过单因素和复配实验对红薯粉相关品质进行了测试。实验表明4种多糖对红薯粉品质有着不同的影响,其中阿拉伯胶对样品断条率影响较大,当阿拉伯胶添加量为0.1%时,样品断条率最低,为23.51%;海藻酸钠主要影响红薯淀粉流变性质,当添加水平为0.5%时,相应的应力、黏度和法向应力分别为76.97 Pa、3.85 Pa?s、-12.53 Pa;黄原胶对红薯粉的硬度性影响较大,当添加水平为0.2%时,其硬度达到18.83 N;果胶主要影响样品的内聚性、咀嚼性,当添加水平为0.3%和0.1%时,样品的内聚性和咀嚼性分别达到0.70 Ratio和20.51 mJ;而使用0.1%阿拉伯胶、0.4%海藻酸钠、0.4%黄原胶、0.3%果胶与0.2%阿拉伯胶、0.3%海藻酸钠、0.4%黄原胶、0.1%果胶复配而成的复合添加剂,其样品拉伸力分别达到0.60 N、0.62 N,断条率分别为23.25%、24.66%,能够显著提升红薯粉的各项性质,改善红薯粉的品质。结果表明可以通过天然多糖复配的方法有效替代红薯粉上产中有害的明矾。     

响应面试验优化玉米淀粉-壳聚糖可食膜的制备工艺

通过响应面法优化玉米淀粉、壳聚糖和甘油的质量分数来制备可食膜,以机械性能（伸长率、抗拉强度）和透湿性（water vapor permeability,WVP）为评价指标,得出二次响应预测模型。结果表明：玉米淀粉、壳聚糖和甘油的质量分数分别为3.71%、0.95%和0.64%时,抗拉强度最大;3 种物料质量分数分别为3.82%、0.50%和1.00%时,伸长率最大;3 种物料质量分数分别为3.52%、0.52%和0.50%时,WVP最小。综合考虑,玉米淀粉、壳聚糖和甘油质量分数分别为3.50%、0.50%和0.67%时,可食膜的性能最优。     

Mechanical and water vapor barrier properties of tapioca starch/decolorized hsian-tsao leaf gum films in the presence of plasticizer

The objectives of this research were to examine the mechanical and water vapor barrier properties of the starch/decolorized hsian-tsao leaf gum (dHG) films as a function of dHG and glycerol concentration. Edible film-forming solutions were prepared by mixing tapioca starch with dHG at different starch/dHG ratios to make a total solid content of 2%. In total, 15–40% glycerol was then added based on the dry film matter. Starch/dHG films were obtained by casting. It was found that the puncture strength, tensile strength, and modulus as well as the inverse of relaxation coefficient of starch/dHG films pronouncedly increased with increasing dHG, accompanied with a decreasing tendency in puncture deformation and tensile strain at break. Such results implied that starch interacted with dHG synergistically, resulting in the formation of a new network to improve the mechanical properties of tapioca starch/dHG films. Mechanical strengths of starch/dHG films decreased and water vapor permeability (WVP) at 75% RH increased with increasing glycerol concentration. However, the plasticizing effect of glycerol became less significant at high dHG concentration, particularly for the puncture deformation and tensile strain at break of the films. Water sorption isotherm results indicated that significant water sorption would only occur at high water activity (about 0.75), and generally became more pronounced with increasing glycerol and dHG concentration, but to a lesser extent for the latter. Dynamic mechanical analysis revealed that the major glass transition of starch/dHG films occurred at about −50 °C.     

Utilization of rice starch with gums in Asian starch noodle preparation as substitute for sweet potato starch

Starch noodles were produced using a medium grain rice starch in the presence of various gums, and physical properties of the noodles were compared with sweet potato starch noodle. Pasting viscosity of the rice starch was lower than that of sweet potato starch (830 vs. 1,618 cp as peak viscosity). The peak viscosity, however, was increased by the addition of gums (0.1% based on dispersion), and especially xanthan was the most effective in increasing the peak viscosity (1,478 cp). The cooking loss for the rice starch noodles (1.5 mg/mL), greater than that for the sweet potato starch noodle (0.2 mg/mL), was effectively reduced to 0.8 and 0.9 mg/mL, respectively, by the addition of locust bean gum (LBG) and curdlan. The addition of LBG or gellen gum also increased the hardness of the rice noodles. Aging (extended retrogradation) the noodles was effective in reducing the cooking loss and improving the textural properties of the rice starch noodles. The combination of the gum addition (like LBG) and aging of the rice starch noodle might be useful for utilizing rice starch as a substitute for sweet potato starch in Asian noodle preparation.     

Combined effect of plasticizers and surfactants on the physical properties of starch based edible films

Films made of potato starch were developed and glycerol as plasticizer and Tween 20, Span 80, and soy lecithin as surfactants were included in the formulation. Films were characterized with respect to water vapor permeability (WVP) and mechanical properties. The wettability of the film solutions was quantified by measuring their surface tension.The incorporation of plasticizers resulted in more flexible and manageable films and higher WVP. At low concentration, Tween 20 was the surfactant that reduced surface tension the most, while at high concentration it was lecithin. In the absence of glycerol, surfactants had a significant effect on mechanical properties, but they did not modify significantly WVP of the films. It was observed a synergistic behavior between the plasticizer and the surfactants. Films with glycerol and high level of any of the surfactants behaved as films with larger amount of plasticizer (with lower tensile strength, higher elongation, and higher WVP). Tween 20 was the surfactant that showed the most intense synergistic effect with glycerol.     

甘薯淀粉-魔芋葡甘露聚糖膜性能研究

可食用性包装材料被认为是可以直接被食用的特殊包装材料,可食用性淀粉包装薄膜是其研究和应用最为广泛的一种,而其中的甘薯淀粉薄膜更是具有代表性。本文主要探索和研究不同浓度魔芋葡甘露聚糖的加入对甘薯淀粉薄膜的拉伸强度、吸湿度、透气性、透湿性和色差等指标的影响,希望能为进一步加快可食用性淀粉膜的深层技术开发、相关产品能够早日面市和大规模应用提供一定的数据参考。研究的结果表明:当魔芋葡甘露聚糖浓度(g/100g淀粉)为3%7%时,薄膜的断裂伸长率有上升,将对薄膜的脆性有一定的改善;当淀粉浓度在4%时,薄膜的抗张强度和断裂伸长率均有较好表现。另外魔芋葡甘露聚糖的添加使透湿性和透气性都有显著的降低,但对薄膜色泽的影响不明显。