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1.
谷氨酰胺转移酶对大豆分离蛋白成膜性能的影响   总被引:9,自引:0,他引:9       下载免费PDF全文
研究了谷氨酰胺转移酶(TGase)对大豆蛋白膜特性的影响。研究表明:在成膜溶液中加入TGase(4U/g)可以使膜的抗拉强度增加16.79,6,表面疏水性增加39.2%,同时也明显降低了膜的断裂伸长率、水分含量、总可溶性物质量及透光率,但是对水蒸气转移速率几无影响。扫描电镜(SEM)显示,酶法交联膜的表面比对照膜略为粗糙,断面却更为均匀致密。SDS-PAGE分析表明,TGase催化SPI产生了共价交联。  相似文献   

2.
SPI/MC关混可食膜的性能研究   总被引:1,自引:1,他引:0  
研究了甲基纤维素(MC)对以甘油为增塑剂的大豆分离蛋白(SPI)膜物理性质的影响.结果表明:SPI膜的抗拉强度和表面疏水性随着MC添加量的增加而显著提高(P≤0.05),在添加量为20.0%(w/w,SPI)时相对于对照样分别提高了66.32%和25.39%;断裂伸长率随着MC添加量的增加而先增大后降低,在添加量为10.0%时最大;膜的透光率、水分含量、可溶性干物质总量和水蒸气透过系数随着MC添加量的增加而降低(P≤0.05),在添加量为20.0%时相对于对照样分别降低了41.58%、14.02%、26.55%和20.86%.  相似文献   

3.
研究了底物蛋白的浓度、增塑剂的浓度、蛋白溶液预热处理的温度和时间及变性剂(2-巯基乙醇)处理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.随着底物蛋白质量浓度(3~9 g/dL)的增加,TGase改性SPI膜的TS值和EB值明显增加,而接触角和透光率明显下降.随着甘油含量增加,TGase改性SPI膜的TS值和接触角明显降低,透光率略有降低,而EB值和MC值明显增加.随着蛋白溶液预热处理温度(70~90 ℃)和时间(0.5~1.0 h)的增加,SPI膜的TS值明显增加,接触角和透光率稍有增加,TSM值略有下降.变性剂2-巯基乙醇(2-ME)的加入,使TGase改性SPI膜的TS值、接触角明显增加,MC值明显下降,TSM值和透光率变化不大.  相似文献   

4.
工艺条件对酶法改性大豆蛋白膜性能的影响(Ⅰ)   总被引:1,自引:1,他引:0       下载免费PDF全文
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.  相似文献   

5.
本文研究了以甘油为增塑剂时,十二烷基磺酸钠(SDS)对大豆分离蛋白(SPI)膜功能特性的影响。结果表明:SDS可改善SPI膜的功能特性.显著提高了膜的延展性和阻水能力。当膜液中SDS的添加量为SPI的20%时,膜的断裂伸长率最大,为221%,比对照提高了301%;透光率最大,为43.6%,比对照提高了98%;膜的水分含量为22.2%,比对照降低了7.5%;膜的水蒸气透过率为7.8gmm//m^2 hkPa,比对照降低了23%。但添加SDS也使膜的抗拉强度有所降低,膜的厚度、膨胀率、总可溶性物含量增加。  相似文献   

6.
张春红  王翀  赵前程 《粮油加工》2008,8(3):112-114
本文研究了以甘油为增塑剂时,十二烷基磺酸钠(SDS)对大豆分离蛋白(SPI)膜功能特性的影响。结果表明:SDS可改善SPI膜的功能特性.显著提高了膜的延展性和阻水能力。当膜液中SDS的添加量为SPI的20%时,膜的断裂伸长率最大,为221%,比对照提高了301%;透光率最大,为43.6%,比对照提高了98%;膜的水分含量为22.2%,比对照降低了7.5%;膜的水蒸气透过率为7.8gmm//m^2 hkPa,比对照降低了23%。但添加SDS也使膜的抗拉强度有所降低,膜的厚度、膨胀率、总可溶性物含量增加。  相似文献   

7.
研究了菜豆属类分离蛋白(芸豆、红豆、绿豆)成膜性与大豆分离蛋白成膜性的比较.结果表明,菜豆属类的三种分离蛋白质膜在机械性和透光率方面不如大豆分离蛋白质膜;而表面疏水性上却相反.另外,水分含量和水分吸附特性上表现出一致性,菜豆属类蛋白(芸豆和红豆)有较强的吸附水能力.在水蒸气透过率方面,菜豆属蛋白膜和大豆蛋白膜之间有显著性差异,并发现这与膜的厚度有相关性.但在总可容性物质量上,菜豆属蛋白膜和大豆蛋白膜之间却没有显著性差异.  相似文献   

8.
不同pH下阿魏酸对大豆分离蛋白膜性能的影响   总被引:7,自引:2,他引:5  
本文报道了阿魏酸、pH及碱液等对大豆分离膜的的影响。以大豆分离蛋白为主要基质的成膜溶液调pH、热处理后铺板干燥,揭膜,在相对湿度为52%的室温环境下平衡48h后测定膜的抗拉强度、断裂伸长率、水蒸气透性、颜色等。结果表明,大豆蛋白膜的断裂伸长率随pH的升高而增加,抗拉强度在中性pH以上时也是随pH升高而增加;阿魏酸的添加可显著增加膜的拉伸张力和断裂伸长率,但也使膜的颜色变深;阿魏酸还使我们可以在成膜溶液pH为中性时制备具有较强抗拉强度的膜:加阿魏酸100、200、300mg(此用量分别相当于大豆分离蛋白的2%、4%、6%)将成膜溶液pH调为7.0,与对照相比,可使断裂伸长率提高24.2%~54.4%,抗拉强度提高62.5%~94.3%。  相似文献   

9.
以胶原蛋白与大豆分离蛋白为原料制备复合膜,综合考虑复合膜的拉伸性能(抗拉强度与断裂伸长率),并与市场上的胶原蛋白肠衣的拉伸性能及专利数据进行比较,确定所制膜的拉伸性能目标,利用完全析因设计试验进行制膜工艺优化。在单因素试验的基础上选取试验因素和水平,试验研究了胶原蛋白与大豆分离蛋白质量比、甘油用量(占复合物质量的百分比)、成膜液pH值及处理温度对复合膜抗拉强度与断裂伸长率的影响。发现质量比、甘油质量分数、成膜液pH值及处理温度对复合膜抗拉强度的影响较大,影响程度依次是处理温度质量比pH值甘油质量分数;甘油质量分数和处理温度对复合膜断裂伸长率的影响较大,影响程度依次是处理温度甘油质量分数。最终得到最佳工艺参数:胶原蛋白与大豆分离蛋白质量比2∶1,甘油质量分数30%,成膜液pH值10.0,处理温度40℃时,复合膜的综合拉伸性能最佳,即抗拉强度和断裂伸长率分别为21.15MPa和21.05%。该复合膜的拉伸强度基本达到了胶原蛋白肠衣应用的要求,具有一定的应用价值。  相似文献   

10.
本研究以脱脂南极磷虾粉为原料,采用碱溶酸沉法提取分离蛋白,以磷虾分离蛋白、甘油和水构建成膜体系,以乳清分离蛋白和大豆分离蛋白为对照样品,在相同的成膜条件下,评估磷虾分离蛋白的成膜能力。结果表明,在该膜体系中,磷虾分离蛋白膜的厚度(0.070±0.002)mm、水分含量(15.53%±0.70%)和不透明指数(1.22±0.06)与大豆分离蛋白膜无显著差别。扫描电镜结果表明:热处理后磷虾蛋白膜的表面和截面均表现为细密、平滑、无空隙的结构,具有良好的成膜能力。热处理后磷虾蛋白膜的断裂伸长率为21.09%±0.39%,显著高于未加热的磷虾分离蛋白膜(8.13%±0.41%),小于大豆分离蛋白膜;但三者的拉伸强度无明显差异。实验证明磷虾分离蛋白具有成膜能力,可以在食品加工中用于构建成膜体系。  相似文献   

11.
Jang Woo Park  Seung Yong Cho 《LWT》2008,41(4):692-700
Gelatin-based edible films were produced by extruding hot melt of gelatin-based resins through a die with slot orifice and followed by heat-pressed method. The resins were plasticized with glycerol, sorbitol and the mixture of glycerol and sorbitol (MGS). The effect of type of plasticizer on extruded and heat-pressed (EHP) film-forming capacity was studied, and the mechanical and water barrier properties of resulting EHP gelatin films were compared with those of gelatin films prepared by solution casting method. Stretchable films were formed when glycerol or MGS were used as plasticizer, whereas resins plasticized with sorbitol were extruded in non-stretchable sheets. Glycerol plasticized gelatin film showed the highest flexibility and transparency among the EHP films tested. Tensile strength (TS), elongation (E) and water vapor permeability (WVP) of glycerol plasticized EHP gelatin films were 17.3 MPa, 215.9% and 2.46 ng m/m2 s Pa, respectively, and EHP gelatin films had higher E values, lower TS values and higher WVP values compared to the glycerol plasticized cast gelatin films.  相似文献   

12.
Effects of plasticizers (glycerol, sorbitol, and 1:1 mixture of glycerol and sorbitol) on moisture sorption characteristics of hydrophilic soy protein isolate (SPI) films were investigated at three levels of plasticizer concentration (0.3, 0.5, and 0.7 g plasticizer/g SPI). The combined effects of relative humidity and plasticizer on mechanical properties of soy protein films were also examined. Moisture affinities of soy protein films were affected by hydrophilicity of plasticizer and its concentration. Under given RH conditions, films with higher glycerol ratio absorbed more moisture with higher initial adsorption rate, and films with higher plasticizer contents exhibited higher equilibrium moisture contents. Monolayer moisture contents of SPI films increased as glycerol ratio in a plasticizer mixture and plasticizer concentration increased. Plasticizer and absorbed water loosened the film synergistically, resulting in higher elongation but lower tensile strength. RH effects on mechanical properties of SPI films were varied with plasticizers and their concentration. Films of lower glycerol contents were more sensitive to RH variation as compared to the higher glycerol samples, whereas sorbitol concentration affected the RH region where a sharp decrease in TS value occurred.  相似文献   

13.
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。  相似文献   

14.
The effects of processing parameters, including the applied amount of microbial transglutaminase (MTGase), the pH of film-forming solution, air-drying temperature, as well as the additional pre-incubation, on the properties of MTGase-treated soy protein isolate (SPI) films were investigated. The treatment with low concentration of MTGase (4–10 units per gram of SPI, U g 1) significantly increased the tensile strength (TS) values of SPI films, while high concentration of MTGase (over 20 U g 1) resulted in significant decrease in the TS values (P  0.05). The elongation at break (EB) values of corresponding films gradually decreased, and the contact angle values persistently increased with the enzyme concentration. At alkaline pH range, the TS and EB values of MTGase-treated SPI films were significantly higher than that at pH 7.0 (P  0.05). Meanwhile, the contact angle values significantly decreased with increasing pH from 7.0 to 10.0 (P  0.05). The TS, EB and contact angle values of MTGase-treated films gradually but insignificantly decreased with increasing the air-drying temperature from 18 to 50 °C (P > 0.05). The properties of MTGase-treated films were also affected by the additional pre-incubation of film-forming solutions with MTGase before casting. Furthermore, the aggregation of SPI or its components induced by MTGase has been proved to mainly account for the influence of processing parameters on the properties of SPI films (MTGase-treated). Thus, low concentration of enzyme, alkaline pH range and low air-drying temperature, at which conditions the MTGase-induced aggregation of SPI in film-forming solutions could be in some extent inhibited or delayed, might facilitate the improvement of the properties of SPI films by MTGase, especially the mechanical and surface hydrophobic properties.Industrial relevanceThe development of biodegradable protein film has attracted a lot of attention worldwide. The enzymatic cross-linking induced by transglutaminase has been confirmed to improve mechanical and surface hydrophobic properties of cast films from most of food proteins, including soy proteins. Results of this study show that, the improvement of properties of cast films of soy proteins by transglutaminase treatment is largely dependent upon many processing parameters, e.g., enzyme concentration, the pH of film-forming solution and temperature.  相似文献   

15.
Pea starch films were produced with various plasticizers (glucose, fructose, mannose, sorbitol, and glycerol). Effects of plasticizer content (4.34 to 10.87 mmol/g of dry starch) and storage relative humidity (RH) (11.3% to 75.4%) on moisture content (MC), tensile strength (TS), elongation (E), modulus of elasticity (EM), and water vapor permeability (WVP) were evaluated using response surface methodology. MC was influenced strongly by RH. Glycerol-plasticized films had the highest MC, indicating that water molecules played a more important role in plasticizing starch films. Monosaccharide-plasticized films and polyol-plasticized films had similar TS values. However, monosaccharide-plasticized films had higher E values and lower EM values than polyol-plasticized films, meaning monosaccharides had better efficiency in plasticizing starch films. Recrystallization happened in glucose- and sorbitol-plasticized films when they were stored in high RH. Sorption isotherm studies showed the similar adsorption and desorption profiles for all 3 monosaccharide-plasticized films and a hysteresis. The Flory-Huggius model fitted experimental data best for starch films, while the BET model fitted the data marginally.  相似文献   

16.
Effects of glycerol (3-7% w/w) and sorbitol (4-8% w/w) concentration, pH (7.0, 9.0, 11.0) and heating (90 °C, 20 min) of film-forming solution (FFS) on the water vapor permeability (WVP), moisture content (MC), solubility, light transmission and transparency of pea protein isolate (PPI) films were investigated. Films plasticized with sorbitol exhibited significantly lower WVP, lower MC and higher solubility, in comparison with glycerol-plasticized films. Increasing glycerol content of the films led to increases in WVP and MC but did not affect film solubility. In contrast, increase in sorbitol content had no effect on permeability and MC but resulted in increased film solubility. Moisture sorption isotherms of PPI films suggested that the difference in WVP observed among films plasticized with glycerol and sorbitol might be due to the different hygroscopicity of these plasticizers. The pH of FFS did not have a significant effect on WVP and MC. Solubility of PPI films formed from non-heated FFS was not affected by pH, whereas solubility of films formed from heat-treated FFS generally increased when pH was increased from 7.0 to 11.0. Heating of FFS resulted in improved film transparency. All tested films were characterized by excellent ability to absorb UV radiation. Microstructural observation by scanning electron microscopy did not show differences between sorbitol- and glycerol-plasticized films.  相似文献   

17.
The mechanical, hydrophobic and thermal properties of cast films of vicilin-rich protein isolates from three Phaseolus legumes were investigated and compared to that of soy protein isolate (SPI). The influence of heat curing at 85 °C on the properties of these films was characterized. The films of vicilin-rich protein isolates exhibited much less mechanical strength (TS) and elongation at break (EB) and similar film surface hydrophobicity, as compared with those of the SPI film. The heating remarkably improved the TS of these films, and the extent of the improvement much higher than that of the SPI film, while the EB was only slightly affected. The thermal properties of these protein isolate films were variable, and much distinctly affected by the heating of the films, to a various extent, depending on the type of protein isolates. Protein solubility analyses indicated strengthened hydrogen and hydrophobic bondings of these films by the heating. The results suggest that those vicilin-rich protein isolates have good potential to form cast films with mechanical strength comparable to that of SPI film.  相似文献   

18.
The mechanical properties, opacity, and water vapor permeability of 5.0 % (w/w) canola protein isolate (CPI) films were investigated in the presence and absence of 1 % (w/w of CPI) genipin, and as a function of plasticizer-type [50 % (w/w of CPI); glycerol, sorbitol, and polyethylene glycol 400]. Findings indicated that tensile strength (TS), puncture strength (PS), and elastic modulus (E) values for CPI films prepared with sorbitol were the highest, followed by PEG-400 and then glycerol, whereas tensile elongation (TE) and puncture deformation (PD) values were greater for films prepared with glycerol, followed by PEG-400 and then sorbitol. In all cases, films prepared with genipin were stronger (greater TS, PS, and E) and less flexible (lower TE and PD) than uncross-linked films. Films also showed greater water vapor permeability when prepared with glycerol, followed by PEG-400 and then sorbitol; however, no differences were observed in the presence and absence of genipin. Opacity was least with glycerol present, followed by sorbitol and PEG-400, and increased in the presence of genipin.  相似文献   

19.
Glycerol-plasticized gelatin edible films with a new kind of dialdehyde polysaccharide, dialdehyde carboxymethyl cellulose (DCMC) as crosslinking agent are successful prepared using casting techniques. The mechanical properties, thermal stability, light barrier properties, swelling behavior as well as water vapor permeability (WVP) of the gelatin-DCMC films are investigated. The results indicate that the addition of DCMC causes tensile strength (TS) and thermal stability to increase and elongation at break (EB) to decrease, suggesting the occurrence of crosslinking between gelatin and DCMC. The light barrier measurements present high values of transparency at 280 nm and low values of transparency at 600 nm of the gelatin-DCMC films, indicating that gelatin-DCMC films are very transparent (lower in transparency value) while they have excellent barrier properties against UV light. Moreover, the values of transparency at 280 nm increase with the increased DCMC and glycerol content, suggesting the potential preventive effect of gelatin-DCMC films on the retardation of product oxidation induced by UV light. Furthermore, the addition of DCMC can greatly decrease the water vapor permeability (WVP) and equilibrium swelling ratio (ESR) down to values about 1.5 × 10−10 g m/m2 s Pa and 150%, revealing the potential of DCMC in reducing the water sensitivity of gelatin-based films. In common for hygroscopic plasticizer in edible films, the addition of glycerol gives increase of EB and WVP and decrease of thermal stabilities and ESR of the gelatin-DCMC films.  相似文献   

20.
大豆分离蛋白成膜工艺优化   总被引:2,自引:1,他引:1  
本文以大豆分离蛋白(SPI)为成膜基质,研究了单宁、可溶性淀粉、微波、超声及干热处理对SPI膜性能的影响,并优化了SPI成膜工艺,结果表明:单宁与可溶性淀粉可极显著(P<0.01)降低膜的透光率、水溶性、氧气及水蒸气透过性,可溶性淀粉可极显著(P<0.01)提高膜的抗拉伸强度;微波与超声处理可极显著(P<0.01)降低...  相似文献   

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