阳离子对SPI膜性能的影响

本论文采用湿法工艺制备可食性大豆分离蛋白膜(SPI),通过添加Na 、Zn2 、Fe3 ,考察了阳离子价态对SPI膜性能的影响。结果显示,阳离子价态对SPI膜的透光率(TP)没有影响;使SPI膜的水蒸气透过系数(WVP)增加;添加有0.5%(w/w SPI)的Fe3 的SPI膜的整体性能比较好。     

阴离子对SPI膜性能的影响

本论文采用湿法工艺制备可食性大豆分离蛋白膜(SPI),通过添加氟离子.硫代硫酸根离子、碳酸根离子.焦磷酸根离子,磷酸根离子,考察了阴离子价态对SPI膜性能的影响.结果显示,阴离子价态对SPI膜的透光率没有影响;使SPI膜的WVP增加;添加有2.0%(w/wSPI)的CO32-的SPI膜的整体性比较好.     

大豆分离蛋白膜最佳成膜条件研究

本论文采用湿法工艺制备可食性大豆分离蛋白膜(SPI膜),通过L9(34)正交实验,考察了SPI浓度,甘油浓度,pH和温度四个因素对SPI膜性能的影响.结果显示,在SPI浓度为5.0 %(m/m),甘油浓度为2.0 %(m/m),pH为10,温度为90 ℃时得到的膜综合性能最佳.     

还原剂影响可食性大豆分离蛋白膜性能的研究

研究了还原剂对可食性大豆分离蛋白 (SPI)膜性能的影响。结果表明 ,还原剂可明显提高SPI膜的抗拉强度 (TS) ,降低水蒸气迁移系数 (WVP) ,但伸长率 (E)有所下降。添加还原剂的SPI膜在 pH 7时机械强度和阻隔性最好 ,其中添加半胱氨酸的SPI膜 TS最大 ,为14.4 8MPa ,WVP最小 ,为 4 .6 1g·mm/m2 ·d·kPa     

成膜介质和还原剂对大豆分离蛋白膜性能的影响

研究了成膜介质和还原剂对大豆分离蛋白膜(SPI)性能的影响。结果表明,大豆分离蛋白在自制玻璃板上成膜效果最好;亚硫酸钠可明显提高SPI膜的抗拉强度,对透气度和透光率影响不显著;添加0.1%亚硫酸钠的SPI膜抗拉强度最大,超过0.1%,抗拉强度下降明显。     

大豆分离蛋白膜工艺参数的设计

以大豆分离蛋白(SPI)为主要原料,添加甘油(GLY)制成可食性膜,研究了成膜介质和成膜方法对膜性能的影响;并比较酸性和碱性条件下可食性膜的性能,选择出最佳的成膜工艺参数.酸性条件:蛋白质与甘油的比例2:1、pH为3、温度80℃、底物浓度8%;碱性条件:蛋白质与甘油的比例3:1、pH为10、温度90℃、底物浓度10%.     

工艺条件对酶法改性大豆蛋白膜性能的影响（Ⅰ）

研究了酶浓度、成膜溶液的pH值、干燥温度等工艺参数对谷氨酰胺转移酶(TGase)改性大豆分离蛋白(SPI)膜性能的影响.SPI膜制好后裁切成所需要的样品形状,放在相对湿度为50%的环境中平衡48 h,测定抗拉强度(TS)、断裂伸长率(EB)、水分含量(MC)、总可溶性物质量(TSM)、表面疏水性(S0)及透光率等各项指标.研究表明低浓度的酶浓度改性可显著(P≤0.05)增加SPI膜的TS值和S0值,而降低TSM值.TGase改性使EB值下降,酶浓度越高,EB值下降得越多.TGase改性膜的S0值和TSM值随着酶浓度的增加而增加.成膜溶液的PH值显著影响TGase改性SPI膜的TS值和S0值.TGase改性SPI膜的TS值、EB值和S0值随着干燥温度从18℃增加到50℃而逐渐下降.     

谷朊粉-大豆分离蛋白复合膜成膜条件研究

以谷朊粉为主要原料并添加适量的大豆分离蛋白(SPI)制备复合蛋白膜,研究了不同成膜条件(如SPI、甘油、亚硫酸钠和硫酸钙添加量等)对膜性能的影响,并考查了亚硫酸钠的作用。结果表明,在成膜过程中,增加SPI的比例可提高膜的抗张强度,但降低膜的延伸性能;增加甘油添加量时膜的延伸性提高,但膜的抗张强度下降且透水率增加;添加亚硫酸钠可以明显改善复合膜的抗张强度,但导致透水性增大。在单因素试验的基础上,以膜的透水性、抗张强度和延伸性加权分析结果为指标,用正交试验优化的成膜条件为:大豆蛋白占总蛋白比例为25%、亚硫酸钠添加量为0.25%、甘油为25%、硫酸钙为0.75%时所得复合蛋白膜的性能最佳。     

大豆分离蛋白-水溶性大豆多糖可食性复合膜的制备与性质

以大豆分离蛋白(soy protein isolates,SPI)和水溶性大豆多糖(soluble soybean polysaccharides,SSPS)为主要原料进行了可食性复合膜的制备与性质研究。综合考虑SPI与SSPS的比例、甘油、海藻酸钠添加量及钙离子浓度等影响因素,通过单因素与正交实验对成膜配方进行研究,得到了复合膜的最佳配比,并从水溶性、水蒸气透过性、抗拉伸强度、断裂延伸率等方面对膜的性质进行了综合评价。结果显示:在SPI∶SSPS质量比为1∶7,甘油添加量2%,海藻酸钠添加量4%,Ca2+浓度为1.0mol/L的条件下,复合膜的综合性能评分最高,为67.8。     

冷冻保藏对大豆分离蛋白膜机械性能的影响

用大豆分离蛋白(SPI)制备可食性包装膜时,在成膜溶液中分别添加单甘酯、葡萄糖制成大豆分离蛋白膜,将其分别在室温下(RH65%)保存2d以上和在冷冻保藏7d后测定机械性能,发现添加这些物质后制得的膜的机械性能均受到影响:含单甘酯的膜的抗拉强度(TS)增加超过25%,断裂伸长率(E)变化不大;而含葡萄糖的膜TS增加了35%以上,E增加了55%以上。冷冻对各种SPI膜的机械性能有不同影响,对含葡萄糖的SPI膜的抗拉强度影响很大,TS下降达50%,对其他SPI膜的影响不太大,这意味着不含葡萄糖的SPI膜可用于冷冻食品包装。     

微波处理对植物蛋白基可食膜特性改善效果的研究

通过微波处理以谷朊粉（WG）、大豆分离蛋白（SPI）为主要成膜原料的可食保鲜膜，研究其对可食膜特性的改善作用，结果表明微波处理能有效改良三种膜的机械性能、感官性能及通透性，特别是对WG／SPI膜的改良效果最好。利用扫描电子显微镜对微波处理前后蛋白膜的微结构进行研究，微波处理对膜的微结构有明显的改善作用，可使膜表面更光滑平整，使膜的横截面更均匀、规则、致密，其中对WG／SPI膜的改善效果最明显。经微波处理后WG膜、SPI膜、WG／SPI膜的横截面微结构接近。微波处理后膜的结构改善效果与膜的外观、机械性能、通透性的改善效果一致。     

The effects of ultrasonic/microwave assisted treatment on the properties of soy protein isolate/microcrystalline wheat-bran cellulose film

Wheat-bran cellulose (WC) and microcrystalline wheat-bran cellulose (MWC) were prepared, and edible films containing different ratios of soy protein isolate (SPI) with WC, MWC, and ultrasonic/microwave modified MWC (MMWC) were made by casting. The different proportions and particle size of the fillers (WC, MWC, and MMWC) affected the properties of each of the films. The SPI/MMWC film demonstrated the best properties: MMWC had a smaller particle size and more free hydroxyls on the surface, enabling the formation of stronger intra-molecular hydrogen bonds with SPI that yielded a blend film with a homogeneous, compact structure. The different thermal properties of the films were also mainly attributed to their structures. In addition, FT-IR showed the association between SPI and the fillers, while SEM showed that the surface morphology of the SPI/MMWC film was smoother and more homogeneous.     

几种多糖和交联剂对可食性大豆分离蛋白膜性能的影响

为了提高可食性大豆分离蛋白膜的性能,研究了多糖和交联剂对可食性膜性能的影响。结果表明,在大豆分离蛋白成膜液中添加0.5%(W/V)的果胶能有效增加膜的机械强度,添加0.1%(W/V)的葡萄糖能有效降低膜对水蒸气、氧气的透性。因此,果胶和葡萄糖对其性能的改善效果较佳,果胶和葡萄糖能改善大豆分离蛋白成膜特性的可能机理是因为它们增加了蛋白分子之间的交联。     

改善大豆分离蛋白膜性能的研究进展

大豆分离蛋白膜可用于水果和肉制品的涂膜保鲜及可食性包装等,是一种很有发展前途的可食性膜,但与其他可食性膜相比,其阻湿性能和机械性能较差,需采用适当的处理方法来改善。常用的处理方法有：热、碱处理、还原剂处理、交联剂处理,添加脂类处理,超声波处理,紫外辐射处理,超高压处理,复合膜处理等。其中,复合膜具有复合的几种材料各自所成膜的优点,是可食性膜今后的发展方向。     

乳酸链球菌素与植酸大豆蛋白复合膜的功能特性

为了开发新型大豆蛋白可食膜,将天然减菌剂乳酸链球菌素（Nisin）和植酸加入到大豆蛋白膜中,研究它们对膜的遮光、隔氧、阻湿功能及蛋白质交联度和膜结构的影响。结果表明：添加Nisin会引起大豆分离蛋白膜阻湿性和蛋白质交联度下降,但遮光性和隔氧性增强。植酸对膜的遮光性、阻湿性、隔氧性和蛋白质的交联度的影响与其添加量有关。电镜扫描分析结果表明,大豆分离蛋白膜表面平整光滑,添加了Nisin后,膜中出现复杂纹路,但仍然呈大理石状;继续加入植酸,膜的大理石状结构遭到了破坏。     

共干燥技术在蛋白质/多糖膜制备中的应用

为了改善蛋白基可食性膜的阻水性和机械性，选择大豆分离蛋白作为基料，多糖藻酸丙二醇酯（PGA）、果胶、卡拉胶、芦荟多糖作为增强剂，甘油作为增塑剂，考察共干燥技术在形成蛋白质／多糖复合型可食性膜中的应用，及对膜阻水性和机械性的影响。研究结果表明，蛋白质和多糖通过共干燥法比多糖直接加入法所形成的膜的机械性、阻水性均有一定程度的改善。而且，在两种多糖的加入方式下，形成的SPI／多糖膜的WVP由低到高都可依次排为：SPI／藻酸丙二醇酯〈SPI／果胶〈SPI／卡拉胶〈SPI／芦荟多糖。     

十二烷基磺酸钠(SDS)在大豆分离蛋白基可食性膜中应用

该文报道研究十二烷基磺酸钠应用于以甘油作为增塑剂的大豆蛋白基可食性膜后对其物理性质影响。研究结果表明:当SDS添加量为40%(十二烷基磺酸钠质量/大豆分离蛋白质量)时,薄膜抗拉强度(TS)值显著(p<0.05)减少43%,最大断裂伸长率(E)值显著(p<0.05)增加至少5%,水分含量(MC)值显著减少(p<0.05),总可溶性物质含量(TSM)值显著增加(p<0.05);当SDS添加量>10%时,WVP值下降50%;SDS添加量为20%、30%、40%时,膜颜色值为显著+b (p<0.05),即黄色值增加。     

Edible oxygen barrier bilayer film pouches from corn zein and soy protein isolate for olive oil packaging

An edible oxygen barrier film pouch was fabricated from a heat sealable corn zein (CZ) layer laminated on soy protein isolate (SPI) film and used to package olive oil condiments for use with instant noodles. The mechanical, barrier, and physical properties of the CZ/SPI bilayer films were then investigated and the oxidative stability of olive oil in the pouches was measured during storage under dry and intermediate relative humidity conditions. When compared to the SPI film, lamination with an additional layer of CZ film led to increased tensile strength and water barrier properties, while it had a lower elongation at break and decreased oxygen barrier properties. Nevertheless, the oxygen permeability of the CZ/SPI film (0.81 × 10⁻¹⁸ m³ m/m² s Pa) was lower than that of nylon-metalocene catalyzed linear low-density polyethylene (NY/mLLDPE) film (3.51 × 10⁻¹⁸ m³ m/m² s Pa) which is the material usually used for such condiments. The CZ/SPI bilayer films generated here were heat sealable at 120-130 °C and produced a seal strength greater than 300 N/m. The higher oxygen barrier property of the CZ/SPI bilayer films resulted in reduced oxidative rancidity of olive oil packaged in the CZ/SPI film when compared to olive oil packaged in NY/mLLDPE films.     

The impact of anthocyanin-rich red raspberry extract (ARRE) on the properties of edible soy protein isolate (SPI) films

To modify the properties of edible soy protein isolate (SPI) films, 0.5% anthocyanin-rich red raspberry (Rubus strigosus) extract (ARRE) (0.5 g raspberry powder in 95% ethyl alcohol/water/85% lactic acid [80:19:1. v/v/v]) was incorporated into film-forming solutions. ARRE resulted in an SPI film having significantly enhanced tensile strength (P < 0.05) and % elongation at break (P < 0.05), as well as increased water swelling ratio (P < 0.05) and in vitro pepsin digestibility (P < 0.05). The resultant films also showed significantly decreased water solubility and water vapor permeability (P < 0.05). In addition, ARRE increased darkness, redness, and yellowness film appearance as evidenced by a lower L* (P < 0.05), greater positive a* (P < 0.05), and a higher b* (P < 0.05) than the control film. Scanning electron microscopy images revealed that extract-added films had denser and more compact cross-section microstructure. Fourier transform infrared spectra illustrated that ARRE-created hydrogen bonding involved conformational changes of soy protein without destroying its backbone structure. SDS-PAGE electrophoretograms revealed that the extract induced intermolecular interaction of the soy protein monomers. Natural plant extracts would be a promising ingredient to make SPI films with different physicochemical properties and applications. PRACTICAL APPLICATION: This study characterizes the potential physicochemical changes of SPI film with incorporated raspberry extract. Upon the above modification, the resultant film was found to enhance the applications of pure SPI film in food packaging. For example, SPI-ARRE film could prolong the usage life of SPI film due to increased strength, or could be useful as a desiccant (drying agent) such as a water-absorbing sheet for preserving dried foods due to its increased hydrophilic surface and water-swelling ratio. SPI-ARRE film could also be alternately used as a food wrap with unique color.