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目的 将真菌Pseudofusicoccum violaceum(P. violaceum) F10产的天然蓝色素添加到明胶基膜中制备成可降解抗氧化性膜, 并探究该膜的抗氧化性能。方法 将天然蓝色素按一定比例添加到明胶、羧甲基纤维素钠(sodium carboxymethylcellulose, CMC)、甘油制备的基础膜液中, 制备成蓝色素膜; 采用响应面优化成膜工艺; 对膜的色素保留率、机械性能、透水性、抗氧化活性及抗油脂光氧化性等进行测定。结果 色素添加浓度在0.02%~0.04%时色素在膜中分布均匀, 浓度增加到0.08%时, 色素分布不均匀、有聚集现象; 单因素试验表明随着蓝色素添加膜的抗拉力强度增强, 伸长率有所下降; 响应面试验结果显示最佳的成膜工艺是明胶2.474 g、羧甲基纤维素钠1.125 g、甘油1.158 g、蓝色素0.03%, 与单因素试验结果基本吻合; 正常光照下膜的色素保留率可达90%以上, 加速光照下膜的色素保留率可维持在80%以上; 蓝色膜的自由基的清除率随色素添加量的增加而增强, 当添加量为0.06%时, DPPH自由基和ABST阳离子自由基的清除率分别为42.3%和32.4%; 与无色素膜相比, 蓝色素膜能使橄榄油的过氧化值(peroxide value, POV)降低45.7%。结论 该蓝色膜有较好色素保留率、机械性能, 同时具备抗氧化活性和抗光氧化性, 本研究可为开发同时具备减缓油脂自动氧化和光氧化的可降解包装膜奠定了理论基础。 相似文献
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绿色包装材料魔芋葡甘聚糖可降解膜的制备研究 总被引:2,自引:0,他引:2
以魔芋精粉为主要原料,利用魔芋葡甘聚糖溶胶在适当条件下的成膜性制备可降解绿色包装膜材料。通过单因素实验和正交实验,探讨了精粉浓度、增塑剂和补强剂的添加量、干燥温度、pH等因素对膜的制备及膜性能的影响,确定了膜制备的最佳工艺条件:即精粉浓度1%(g/mL),增塑剂6%,补强剂6%,干燥温度60℃,pH9~10。 相似文献
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鸡骨明胶具有良好成膜性,明胶浓度为8%,明胶与甘油质量比为6∶1时,明胶膜具有透明光泽、机械强度高。鸡骨明胶与茁霉多糖混合体属热力学不相容体系,共混膜的性质强烈依赖于二者的比例,当m(明胶)∶m(茁霉多糖)=4∶1时,共混膜的阻氧能力提高。制得的胶囊壳的贮藏稳定性好,贮藏过程胶囊的崩解延时现象得到改善。 相似文献
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为延长鸡蛋货架期,以普鲁兰多糖为原料,通过添加甘油、阿拉伯树胶、溶菌酶和几丁质酶,并结合超声工艺制备成可食性复合涂膜保鲜剂。通过水蒸气透过系数和过氧化值的测定,研究各成膜剂质量比、膜液质量浓度、干燥时间、干燥温度和超声时间等因素对普鲁兰多糖复合膜性能的影响。结果表明:普鲁兰多糖、甘油、阿拉伯树胶质量比为3∶1∶2,成膜剂质量浓度为3.0~3.3 g/100 mL、干燥温度60 ℃、干燥时间90 min、150 W超声处理15 min、添加0.75 g/100 mL溶菌酶与几丁质酶(质量比1∶3),此时普鲁兰多糖复合涂膜剂的性能表现最佳,且能有效抑制大肠杆菌、金黄色葡萄球菌、沙门氏菌毛霉和曲霉的生长。在鸡蛋保鲜实验中,25 ℃存放28 d后涂膜组的鸡蛋质量损失率为6.16%,蛋黄指数为0.31,哈夫值下降至67.18,蛋清pH值由7.61上升至8.47,涂膜组鸡蛋品质仍维持在A级水平。综上,普鲁兰多糖复合抑菌涂膜剂具有良好的保鲜效果,能有效抑制腐败细菌和真菌生长。 相似文献
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研究了魔芋葡甘聚糖(KGM)和乙基纤维素(EC)复合膜最优配方,并探究KGM/EC膜在蜂蜜包装中的应用。以KGM、EC和癸二酸二丁酯(DBS)为基材,以水和乙酸乙酯作为溶剂制备KGM/EC膜,在单因素实验的基础上,采用Miscellaneous试验设计结合响应面分析法优化KGM/EC复合膜配方,结果表明,复合膜最佳配方为KGM含量为70%,EC含量为30%,DBS含量为8%时,制备的KGM/EC复合膜拉伸强度最大为64.56 MPa。在此基础上,探究了KGM/EC膜的热封条件,并将膜应用于蜂蜜包装,结果表明,利用2% KGM溶胶作为胶粘剂对KGM/EC膜热封14 s,膜封口强度达最大值4.4 N/15 mm,蜂蜜包装袋在25℃和RH 50%±5%条件下存放22 d,达到水蒸气解吸平衡,失重率为9.3%,蜂蜜中未检出微生物菌落。综上,KGM/EC复合膜可应用于蜂蜜包装。 相似文献
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水相中溶致魔芋葡甘聚糖(KGM)流延干燥成膜,分析膜的力学特性。筛选并确定KGM 质量浓度、制备温度、制备时间、静置时间、干燥温度5 个因素的中心组合试验设计,以拉伸强度为考察指标,采用响应面优化KGM 膜的制备工艺。结果表明:5 个因素对膜的拉伸强度均有显著影响,依次为KGM 质量浓度>制备温度>静置时间>干燥温度>制备时间,且最优条件为2.19g/100mL KGM、60.0℃搅拌190min、静置156min、51.1℃干燥。制备的膜表面平整光滑,拉伸强度最佳,耐水性较好。 相似文献
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采用浸泡热干法制备细菌纤维素-茶多酚复合膜,通过测定复合膜的抑菌性能、力学性能、透光率、吸水 率以及水蒸气透过率和结构的变化,确定茶多酚的最适添加质量分数和浸泡时间,探究细菌纤维素-茶多酚复合膜 的特性及结构,以期得到具有抑菌性强、柔韧性好等特点的复合膜。结果表明:茶多酚质量分数同复合膜的抑菌能 力呈正相关,茶多酚质量分数大于0.2%时。抑菌圈直径开始产生明显变化(P<0.05),表现出对受试菌种较强的 抑菌能力。随着茶多酚质量分数的增加,复合膜的拉伸强度、透光率、吸水率以及水蒸气透过率有所下降,断裂伸 长率和厚度逐渐增加,复合膜变得更加柔韧。从降低生产成本以及对复合膜品质影响较低的角度考虑,确定最适茶 多酚质量分数为0.2%。随着浸泡时间的延长,复合膜各项指标的变化均同茶多酚质量分数对复合膜的影响趋势相 同,但当浸泡时间超过4 h后,各项指标趋于平缓,变化不再明显(P>0.05);因此选择4 h为最佳浸泡时间。细菌 纤维素-茶多酚复合膜具有典型细菌纤维素的特征吸收峰,茶多酚分子存留在细菌纤维素膜内部的同时紧密地连接 在细菌纤维素上,且质地均匀。 相似文献
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建立高效液相色谱法同时测定改性聚乳酸(polylactic acid,PLA)薄膜中香芹酚及百里香酚含量的方法。色谱条件:Sunfire C18色谱柱(4.6?mm×150?mm,3.5?μm),流动相为乙腈-水(3∶2,V/V),色谱柱温(30±5)?℃,流速1?mL/min,等梯度洗脱,进样量10?μL,分析时间10?min,紫外检测器,检测波长274?nm,外标法定量。结果表明:香芹酚和百里香酚在5~100?mg/L范围内线性良好,R2均大于0.996。加标回收率分别为71.6%~93.7%和73.1%~103.6%;相对标准偏差分别为5.2%~8.3%和5.0%~8.8%。香芹酚和百里香酚的检出限均为200?μg/kg,定量限均为500?μg/kg。本方法简便、快速、精确,可为进一步研究食品包装薄膜中香芹酚和百里香酚的迁移机理及薄膜在食品包装中的应用提供依据。 相似文献
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利用溶液共混法将柞蚕丝素添加到聚乳酸基体中,制备柞蚕丝素/ 聚乳酸复合膜,研究柞蚕丝素对聚乳酸塑料性能的改善。结果表明:柞蚕丝素/ 聚乳酸复合膜的成膜特性受制备柞蚕丝素所需磷酸水解时间、柞蚕丝素水溶液质量分数、干燥温度、增塑剂聚乙二醇(400)添加质量分数等因素的影响;在添加磷酸水解3h 的柞蚕丝素水溶液的质量分数2% 时制备的柞蚕丝素/ 聚乳酸复合膜表现出的综合性能指标较好,其拉伸强度19.75~23.89MPa、断裂拉伸应变37.42%~48.20%,具有优异的防水阻油性能;在添加磷酸水解1h 的柞蚕丝素水溶液(质量分数4%)时制备的复合膜对UV-B 区间的紫外遮蔽效果最好,紫外线透过率仅为9.4%~12.7%。经红外光谱测试,柞蚕丝素与聚乳酸基体复合效果良好。 相似文献
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贮前热处理对2℃贮藏黄瓜抗冷性和自由基生物学的影响 总被引:6,自引:0,他引:6
为减轻黄瓜低温贮藏时的冷害,研究了薄膜包装和贮藏前热处理对2℃条件下冷藏3周后黄瓜的冷害指数、失重、腐烂率和活性氧代谢的影响。薄膜包装极显著抑制了黄瓜的严重失水,但对冷害无显著影响,并加重了黄瓜的腐烂。在薄膜包装条件下,42℃热水处理和48℃热水处理防止了黄瓜腐烂的发生,极显著减轻了冷害,提高了活性氧清除酶SOD、CAT和POD活性,从而降低活性氧Q_2·~-和H_2O_2含量,抑制膜脂过氧化。贮前热水处理结合薄膜包装能有效防止黄瓜低温贮藏时的大量失水和腐烂,抑制活性氧代谢失调,极显著降低冷害。 相似文献
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《Food Hydrocolloids》2007,21(5-6):879-888
Synthetic food packaging is classically used to prevent mass transfer of various small molecules (water, gases, flavour compounds or solutes) between a food and its surrounding medium. In the case of composite foods, the development of edible films and coatings, applied between the different phases of this food is rising up. The increase of such food products shelf-life is indeed related to the barrier efficiency of these edible packaging against small molecules transfers. This is especially true for water transfer between compartments of different water activities in the same food, that leads to important physico-chemical changes and therefore to food quality deterioration. Film-forming substances used for this study associated an iota-carrageenan hydrocolloid matrix, that ensures good mechanical properties, in which a high melting point fat was dispersed to enhance moisture barrier properties. After the film drying in standardised conditions of temperature (30 °C) and relative humidity (40%), the emulsified films containing various contents of fat (30%, 60% or 90% dry basis) were also submitted to heat treatment (100, 150, 200 °C) and for different durations (1, 2, 4, 8 min) corresponding to those classically encountered in baking processes. The aim was to tend to a bilayer film structure from a single film manufacturing. Size and repartition of fat globules in the carrageenan matrix was characterised by laser light granulometry and film microstructure was observed by ESEM. Barrier efficiency to water was evaluated from water vapour permeability measurements. Contrary to previous observations on film drying, neither fat globule size nor film water permeability was significantly modified by such heat treatment. Moreover, no phase separation was noticed by microscopic observations of the film cross section. Therefore, carrageenan matrix represents a very powerful material for its structural properties to a system and is a good candidate for application such as encapsulation of active substances incorporated in biopolymer coatings or films for food packaging applications. 相似文献
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Sabina Kokoszka Frederic Debeaufort Andrzej Lenart Andree Voilley 《Journal of the science of food and agriculture》2010,90(10):1673-1680
BACKGROUND: Edible films and coatings based on protein/lipid combinations are among the new products being developed in order to reduce the use of plastic packaging polymers for food applications. This study was conducted to determine the effect of rapeseed oil on selected physicochemical properties of cast whey protein films. RESULTS: Films were cast from heated (80 °C for 30 min) aqueous solutions of whey protein isolate (WPI, 100 g kg?1 of water) containing glycerol (50 g kg?1 of WPI) as a plasticiser and different levels of added rapeseed oil (0, 1, 2, 3 and 4% w/w of WPI). Measurements of film microstructure, laser light‐scattering granulometry, differential scanning calorimetry, wetting properties and water vapour permeability (WVP) were made. The emulsion structure in the film suspension changed significantly during drying, with oil creaming and coalescence occurring. Increasing oil concentration led to a 2.5‐fold increase in surface hydrophobicity and decreases in WVP and denaturation temperature (Tmax). CONCLUSION: Film structure and surface properties explain the moisture absorption and film swelling as a function of moisture level and time and consequently the WVP behaviour. Small amounts of rapeseed oil favourably affect the WVP of WPI films, particularly at higher humidities. Copyright © 2010 Society of Chemical Industry 相似文献
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为优化恩七叶甜绞股蓝龙须茶生产工艺,对该产品杀青温度、时间、料液比、杀青后冷却时间等关键参数进行研究,得出杀青最优组合为A3B1C3D2,即100℃杀青2min,用直径1mm 不锈钢丝做成孔径0.3cm 的透气摊凉床,用风扇床下床面对流吹凉,吹冷时间5min。最优烘干组合为E2F3G1,即杀青温度100℃、烘干4h、在烘干前摊放15min;用本工艺参数生产的产品有效成分含量最高,营养成分损失较少,色香味上乘,产品质量稳定。最优冲泡组合为H2I3J1K2,即在料液比为1:50(g/mL)的80℃开水中浸泡2 次,每次45min,此条件下有效成分和营养成分基本都溶出,并泡出汤清叶绿、色香味保健功能俱佳茶水,对生产品质稳定的龙须茶和对消费者冲泡本产品有较高参考意义。 相似文献