木薯氧化淀粉-壳聚糖复合膜的成膜特性研究

利用木薯氧化淀粉为成膜主要材料,添加增塑剂甘油和增强剂壳聚糖,制备了一种新型可食性淀粉膜.通过研究膜组分和成膜工艺参数对抗拉强度、断裂伸长率、水溶性和透明度等膜性能的影响,确定了制膜最佳工艺条件.正交实验结果表明,氧化淀粉的用量对膜的力学性能起主要影响作用,当m(木薯氧化淀粉):m(壳聚糖):V(甘油)=6:2:3时,在60℃下烘干4h,可制得较为理想的淀粉膜,抗拉强度为4.86MPa,断裂伸长率为130.88%,水溶性和透明度分别为50.31%和87%.     

干热变性莲子淀粉制备工艺对其成膜特性影响的研究

通过将莲子淀粉与海藻酸钠混合均匀后干热反应制得干热变性莲子淀粉,并以其为主要原料制备可食膜,研究不同离子胶用量、反应pH、干热处理的温度和时间对干热变性莲子淀粉成膜特性的影响,确定干热变性莲子淀粉的制备工艺.结果显示:添加海藻酸钠对莲子淀粉进行干热变性处理能改善莲子淀粉的成膜特性,pH和干热温度对干热变性莲子淀粉的成膜性影响最显著.经正交试验优化,当海藻酸钠质量分数为1.0％、pH 7、130℃条件下干热反应3h时制备的干热变性莲子淀粉成膜特性最优,为海藻酸钠与莲子淀粉干热反应的最佳工艺参数.     

柠檬果渣果胶提取工艺研究

研究以柠檬果渣为主要原料提取果胶的最佳工艺条件,采用微波辅助酸法提取柠檬果胶。通过单因素试验研究萃取剂、微波加热时间、加热功率、pH及料液比对果胶提取率的影响。再通过正交试验进一步优化提取条件,得出影响果胶提取率的因素的主次顺序为微波加热时间＞pH＞微波加热功率＞料液比。最终确定了提取果胶的最佳工艺为选用盐酸溶液作为萃取剂,微波加热时间2 min,pH值为2.0,微波加热功率480 W,料液比1∶30（g∶mL）,其提取率为27.96%。     

微波萃取山楂果胶的试验研究

本试验研究了利用微波技术萃取山楂中果胶的新方法,考察了不同溶剂、不同微波功率,以及萃取时间及溶剂用量对果胶萃取率的影响.确定HCl为本试验的最佳萃取溶剂.通过单因素试验正交试验,确定了最佳工艺条件.     

紫甘蓝蔬菜纸的研制

对紫甘蓝蔬菜纸加工过程中的色泽、口味、营养成分进行了研究。先对不同支撑材料、不同黏合剂用量做了单因素研究,在确定了最佳用量范围的基础上,通过正交试验确定黏合剂的最佳添加浓度。结果显示:卡拉胶对蔬菜纸的弹性效果最好,果胶次之,淀粉最差。通过对比试验证明:麻油作为成膜支撑材料,在65℃下热风干燥,菜纸成型效果较好。通过感官指标做正交试验,制备菜纸的最佳配方为:紫甘蓝料浆17 g~18 g,大豆分离蛋白0.5%、卡拉胶0.5%、淀粉0.5%、果胶0.6%。     

羧甲基淀粉/玉米秸秆纤维素复合可食膜的研究

以羧甲基淀粉(CMS)为主要成膜基材,添加羧甲基纤维素钠(CMC)、山梨糖醇(Sorbitol, Sor)和玉米秸秆纤维素(CSC)制备复合可食膜。研究各成膜材料质量浓度对膜的抗拉强度和断裂伸长率的影响,通过响应面试验优化羧甲基淀粉基复合可食膜的最佳制备工艺。结果表明:当CMS质量浓度为3.95 g/100 mL, CMC质量浓度为0.92 g/100 mL, Sor质量浓度为1.64 g/100 mL, CSC质量浓度为0.79 g/100 mL时,膜的抗拉强度和断裂伸长率分别达到19.43 MPa和26.87%。扫描电子显微镜和傅里叶红外光谱分析表明各成膜材料各组分之间的相容性较好,分子间的氢键作用加强。     

高取代度阳离子淀粉的制备与应用

讨论了半干法制备高取代度阳离子淀粉的影响因素,优化出制备高取代度(DS为0.45)阳离子淀粉的最佳工艺条件,并将其作为助留剂应用于漂白麦草浆.研究结果表明,此淀粉对漂白麦草浆有很好的助留效果,当其用量为0.2%时,填料留着率可达87.6%.     

酰胺化果胶最佳胶凝条件的探讨

以商品高酯果胶为原料,制备酰胺化果胶,以胶凝破碎强度为检测指标,得到酰胺化果胶的最佳胶凝条件.以pH值、酰胺化果胶浓度、蔗糖浓度、Ca2+浓度4因素为因素,以去离子水配制溶液,保存温度5℃、保存时间48h进行正交试验得到的最佳胶凝条件为:pH值3.6、酰胺化果胶浓度1.4%、蔗糖浓度30%、Ca2+浓度50 mgCa2+/g酰胺化果胶.     

玉米淀粉与小麦淀粉复合可食用膜工艺研究

以玉米淀粉和小麦淀粉为成膜基质,采用流延法制备可食用膜,以膜的力学性能作为考查指标,通过单因素实验研究质量比、山梨醇含量、柠檬酸含量、增强剂含量、糊化温度、糊化时间对力学性能的影响,在单因素基础上,以四因素三水平的正交实验优化的最佳制膜工艺条件。结果表明,在淀粉溶液浓度60 g/L,玉米淀粉和小麦淀粉质量比40∶60,山梨醇含量0.6%,柠檬酸含量2.5%,增强剂含量1.4%,糊化温度85℃,糊化时间40 min,干燥4~6 h的最佳制膜工艺条件下,复合膜的拉伸强度为14~15 MPa,断裂伸长率为30%~33%。     

菠萝皮渣提取果胶的研究

以热烫后烘干的菠萝皮为研究材料,采用酸解法对菠萝皮渣中果胶的提取工艺进行研究,结果表明:经过热烫处理后的果胶的提取率是3.2%,未经热烫处理的果胶的提取率是2.5%。选用柠檬酸-盐酸作为萃取剂,提取率、色泽优于其它酸萃取剂。酸解法提取果胶的最佳工艺参数为:温度90℃、pH 2.0、时间110min、固液比1:14;在此条件下测得粗果胶的提取率为6.11%。     

橙皮果胶可食性保鲜膜的应用

利用橙皮提取果胶,检测果胶样品的质量,分析得出该果胶产品符合作为食品添加剂的国家标准。利用橙皮果胶为主要原材料制备的薄膜各项指标为:透光率为87.8%,厚度为0.127 mm,抗拉强度为3.983 MPa,断裂伸长率为24.883%。文中还将果胶标准品膜、提取的果胶样品膜和购买的PE膜进行物理特性的分析对比,并应用于猪肉的保鲜,通过分析汁液渗出量、pH值、挥发性盐基氮和细菌总数4个指标的变化,证明橙皮果胶可食性保鲜膜对冷鲜猪肉的保鲜效果明显优于PE塑料保鲜膜,具有良好的实用价值。     

柚皮果胶的提取方法比较及其粘流性能研究

比较了从江永柚皮中提取果胶的不同方法。研究了柚皮果胶溶液的粘流性能,测定了果胶的特性粘度并由此计算出果胶的分子量。结果表明:盐酸逆流萃取法为从柚皮中提取果胶的较好方法,果胶溶液的粘流活化能约为17.14kJ/mol(依赖于果胶浓度大小),采用逆流萃取法提取的果胶特性粘度为4.492ml/g,果胶分子量为7.17×104。     

Characterization of pectin extracted from banana peels of different varieties

Pectins were extracted from banana peels of five different varieties using citric acid solution. The chemical characteristics of banana peel pectins were investigated and compared with citrus peel and apple pomace pectins which were extracted under the same extraction conditions to assess the potential of banana peels as an alternative source of commercial pectin. The yield of banana peel pectins ranged from 15.89 to 24.08%. The extracted banana peel pectins were categorized as high methoxyl pectin with the degree of esterification between 63.15 and 72.03% comparable to those of conventional pectin sources from citrus peel (62.83%) and apple pomace (58.44%). The anhydrouronic acid (AUA) content of banana peel pectins varied from 34.56 to 66.67%. Among various banana varieties being studied, pectin from Kluai Nam Wa variety had the highest AUA content (66.67%) which met the criteria for food additive pectin indicating its commercial significance as an alternative pectin source.     

冻融处理对淀粉膜结构、热稳定性、机械性能及物理性质的影响

本实验分别以天然马铃薯淀粉（potato starch,PS）、改性马铃薯淀粉（包括羟丙基二淀粉磷酸酯（hydroxypropyl distarch phosphate,HDP）、醋酸淀粉（acetate starch,AS）和氧化淀粉（oxidized starch,OS））为基材,通过流延法制备可食用淀粉膜,考察冻融处理对膜物理性质、机械性能、阻隔性能、微观结构和热稳定性的影响。X射线衍射结果表明,马铃薯来源的淀粉颗粒具有典型的B型晶体结构,在成膜过程中淀粉结晶度降低,冻融处理后淀粉膜晶体峰强度明显减弱。扫描电子显微镜观察结果显示,冻融处理破坏了淀粉膜的微观结构,其中PS膜上出现明显裂纹,AS膜上出现蜂窝和层状结构,而HDP和OS淀粉膜具有更完整的形态。热重分析结果表明,随着温度的升高,淀粉膜的热重曲线出现4 个质量损失阶段,分别对应水分散失、甘油挥发、淀粉解聚及淀粉分解,而冻融处理对膜热稳定性影响较小。常温条件下,PS膜具有最佳的机械性能,其拉伸强度为2.29 MPa,断裂伸长率为68.82%。在3 个冻融循环后,淀粉膜的拉伸强度至少增加了2 倍,断裂伸长率普遍降低,而溶解度和水蒸气透过率仅有轻微变化。综合考虑不同淀粉膜微观结构、机械性能、水蒸气透过率及水溶性,HDP膜表现出更好的冻融稳定性,可应用于冷冻低水分食品的保藏。     

Oxygen permeability and mechanical properties of banana films

Banana flour, obtained from banana cv. Kluai Namwa, was used to form banana films. The effect of banana flour, glycerol (Gly) and pectin content on film oxygen permeability (OP) and mechanical properties of banana films were studied. Banana flour content significantly affected film OP; whereas, Gly and pectin contents did not significantly affect film OP. Increasing banana flour and pectin contents enhanced film strength; thus, it showed higher film elastic modulus (EM) and tensile strength (TS) but less film % elongation (% E) (p ⩽ 0.05). In contrast, increasing Gly content reduced the film strength and improved film flexibility; therefore, it decreased film EM and TS but increased film % E (p ⩽ 0.05). Banana films showed good sealability, which can make these films suitable as sachets or pouches for dry foods, thus reducing the need for plastic materials.     

赣州脐橙皮果胶的提取工艺优化及其改性前后理化性质和生物活性的研究

为实现赣州脐橙皮的资源化利用,以超声微波协同萃取法提取赣州脐橙皮果胶（GOP）。采用Box-Behnken试验对工艺参数进行优化,并对获得的果胶进行pH改性,研究改性前后果胶理化性质的变化,进一步研究其体外抗氧化活性,以及对玉米淀粉糊化和体外消化的影响。结果表明,果胶提取的最优工艺条件为:微波功率550 W,微波时间30 min,pH2.4,液料比25.00 mL?g-1,在此条件下,最终GOP得率为18.25%±0.31%。经过改性,其果胶酯化度由74.10%±2.73%下降到33.27%±2.47%、半乳糖醛酸含量由74.65%±1.11%显著（P<0.05）增加至88.19%±2.98%。两种果胶均表现了较良好的抗氧化活性,改性后,果胶的抗氧化能力增强,其浓度为8 mg/mL时,对DPPH、ABTS自由基的清除率分别达到84.35%±0.28%和87.33%±0.43%。果胶的加入显著（P<0.05）提高慢消化淀粉（SDS）和抗性淀粉（RS）的含量,并增加淀粉糊状物中小颗粒的比例,抑制淀粉颗粒的溶胀,从而抑制了淀粉消化。pH改性果胶对淀粉消化的抑制作用优于未改性果胶。本研究为赣州脐橙皮果胶的开发和利用提供理论依据和技术支撑。     

果胶提取影响因素交互作用对提取效果的影响

应用Design Expert7.0软件技术,采用响应曲面法设计、分析,研究提取液pH值、提取温度、提取时间及盐析温度四个因素中的两个因素交互作用对香蕉皮果胶提取得率的影响。结果表明,这四个因素中任两个因素的交互作用都会对果胶提取得率产生影响。尤以提取温度和提取时间交互作用、提取温度和盐析温度交互作用、提取时间和盐析温度交互作用对果胶提取得率影响最为明显。     

Effect of Chitosan Nanoparticles and Pectin Content on Mechanical Properties and Water Vapor Permeability of Banana Puree Films

Abstract: Puree prepared from over‐ripe peeled bananas was used as raw material for films processing in a laboratory padder. Pectin and glycerol as plasticizer were added in small concentrations and chitosan nanoparticles (88.79 ± 0.42 nm medium size) incorporated at 0.2% (dry weight basis) as reinforcement material. The mechanical properties, water vapor transmission, thermal stability, and scanning electron microscopy of fractured film surfaces were characterized. Both pectin and glycerol demonstrated an important role in promoting elongation and film handability as was expected. The incorporation of nanoparticles promoted noticeable improvement of the mechanical properties and acted in reducing the water vapor permeation rate, by 21% for films processed with pectin and up to 38% for films processed without pectin, when compared to the control (puree films with no pectin and nanoparticles additions). Microscopic observation revealed a denser matrix when nanoparticles are incorporated into the films. Practical Application: The development of films from fruit purees head to a new strategy for plastic processing from natural resources. The over‐ripe or even waste banana can be adequately prepared for batch films processed with reasonable mechanical and barrier properties, suitable for applications in the food segment. The addition of small fractions of chitosan nanoparticles, form nanocomposites enhancing mechanical and thermal stability broadening potential film applications.     

Extraction and Characterization of Pectin from Apple (Malus Pumila. Cv Amri) Peel Waste

Abstract

Apple peel, the major waste in preserves manufacturing, contained 1.21% pectin. Peel waste could be stabilized with 600 ppm sulphur dioxide and 1% citric acid. Pectin extraction was better in citric acid than hydrochloric acid. The pectin powder was prepared by triple extraction with citric acid solution (1%) clarification through sedimentation, concentration (24°B), precipitation using ethyl alcohol, vacuum drying and grinding. Physico-chemical properties of pectin powder revealed moisture (10.0%), total ash (1.4%), equivalent weight (652.48), methoxyl content (3.7%), anhydrouronic acid (62.82%), degree of esterification (33.44%), acetyl value (0.68), and jelly grade (80).     

Mechanical Properties, Water Vapor Permeabilities and Solubilities of Highly Carboxymethylated Starch-Based Edible Films

ABSTRACT: Tensile strength (TS), elongation (E), water vapor permeabilities (WVP) and solubilities were determined for highly carboxymethylated starch (HCMS)-based edible films plasticized with sorbitol (S), xylitol (X), mannitol (M) and glycerol (G). TS and E of HCMS-based film increased as the concentration of plasticizer S, M or × increased. TS of the HCMS-based film containing combined plasticizers were higher than those of films containing single plasticizer. The WVP of HCMS-based films seemed to decreased as the concentration of M, X or G plasticizer increased. Increasing plasticizer concentrations in HCMS-based film resulted in decreasing solubility of the films.