亲水胶体对牛皮胶原蛋白肠衣膜性能的影响

为了研究亲水胶体对牛皮胶原蛋白肠衣膜性能的影响,首先以软木纤维素为代表,研究其添加量对胶原蛋白肠衣膜机械性能、溶胀率、水接触角、变性温度等方面的影响;并进一步考察分别添加7种亲水胶体(软木纤维素、微晶纤维素、竹纤维素、魔芋胶、瓜尔胶、羟丙基甲基纤维素和海藻酸丙二醇酯)对肠衣膜性能的影响。结果表明,软木纤维素的添加可使肠衣膜的湿抗拉强度明显增加,溶胀率下降,热收缩率略微降低,热稳定性提升;但当纤维素加入量过高时,肠衣膜的透明度较差,故综合得到软木纤维素的最佳添加量为0.5%(g/g牛皮干基重)。加入海藻酸丙二醇酯肠衣膜的干断裂延伸率最小,约为9%;加入魔芋胶肠衣膜的透明度达到最大值,为35;加入瓜尔胶和魔芋胶的肠衣膜具有最低的热收缩率,约30%。加入微晶纤维素肠衣膜的机械性能、溶胀率、热收缩率及透明度均优于软木纤维素和竹纤维素;FTIR光谱结果表明,7种亲水胶体不会对肠衣膜的化学键产生显著影响。通过添加相应的亲水胶体可获得对牛皮胶原蛋白肠衣膜特定性能的改善。     

壳聚糖/微晶甾醇可食性复合膜的制备、性能及结构表征

以壳聚糖为成膜基质,添加具有抗氧化和抑菌作用的植物甾醇,采用流延法制备壳聚糖/微晶甾醇可食性复合膜,旨在赋予壳聚糖膜抗氧化活性及提高其抑菌性。当甾醇添加量分别为壳聚糖质量的0%~12%时,随着添加比例的增加,复合膜的拉伸强度和断裂伸长率逐渐下降,溶解度和溶胀度逐渐增加,水蒸气透过系数显著降低,对超氧阴离子自由基(O_2~-·)及羟自由基(·OH)的清除率显著提高,对金黄色葡萄球菌和大肠杆菌的抑菌性能明显增强;采用红外光谱、扫描电子显微镜、X射线衍射和热重分析表征了复合膜的相容性。结果表明:甾醇添加量为9%的壳聚糖/微晶甾醇可食性复合膜各项性能指标良好,且壳聚糖与甾醇分子之间形成了分子间氢键,有较强的相互作用,整个共混体系的相容性良好。     

壳寡糖对壳聚糖-明胶-壳寡糖三元复合膜的性能影响研究

以壳聚糖、明胶和壳寡糖进行了复合膜的制备,通过红外光谱表征了其结构,考察壳寡糖添加量对复合膜物理、机械、抗氧化和抑菌性能的影响。结果表明,壳聚糖、明胶、壳寡糖三者之间发生氢键相互作用。适量壳寡糖的加入,可增强复合膜的亲水性,改善力学性能及水蒸气阻隔性能,显著提高复合膜的抗氧化性能和抑菌活性(p0.05)。壳聚糖与明胶的质量比为2∶3,甘油含量为1%(v/v),添加30%的壳寡糖,复合膜的DPPH自由基清除率提高了7.03倍,对大肠杆菌和金黄色葡萄球菌的抑菌圈直径分别增大了32%和30%。     

戊二醛添加顺序对胶原蛋白肠衣膜品质的影响

为了缩减胶原蛋白肠衣膜的制备工序，提高食品行业包装材料的质量，考察了戊二醛的添加顺序对胶原蛋白肠衣膜品质的影响。分别通过制胶时、成胶后以及成膜后3种添加方式，以抗拉强度、断裂延伸率、热收缩率、溶胀率、色泽及变性温度等为指标进行了研究。结果表明：在任一添加方式下，戊二醛都可促进胶原蛋白肠衣膜机械性能和表面疏水性的提高，导致溶胀率和热收缩率的下降；其中，通过FTIR和DSC分析表明，采用成膜后浸入戊二醛方式交联获得的肠衣膜交联效率最高，热稳定性最高，且对肠衣膜性能的提升最为显著；进一步，随着戊二醛添加量的提高，肠衣膜的色泽逐渐变黄，而当添加量超过100 mg/L时，戊二醛交联对肠衣膜品质并无进一步显著提升作用。     

香豆素对鱼鳞明胶可食性膜结构及性能的影响

为开发天然的可食性包装材料,以罗非鱼鱼鳞明胶为原料制备可食性膜,将不同添加量（0、0.03、0.06、0.09、0.12、0.15?g/100?mL）香豆素添加到鱼鳞明胶膜中,研究其对鱼鳞明胶膜物理性质及微观结构的影响。结果表明,香豆素的加入对明胶膜的厚度和含水量无显著影响,但明显降低明胶膜的水蒸气透过率（water vapor permeability,WVP）,且香豆素添加量为0.09?g/100?mL时WVP最小。随着香豆素添加量的增加,明胶膜的拉伸强度和断裂伸长率呈现先上升后下降的趋势,在添加量为0.09?g/100?mL时达到最大值。差示扫描量热分析结果表明香豆素与明胶膜有较好的相容性,且明显提高明胶膜的玻璃化转变温度。扫描电子显微镜、傅里叶红外光谱结果表明香豆素与明胶发生交联作用,在香豆素添加量0～0.09?g/100?mL范围内,随着添加量的增加,二者作用增强,明胶膜表面更均一紧致;继续增加香豆素添加量,复合明胶膜性能和结构发生劣变。添加香豆素能有效降低明胶膜的紫外和可见光透光度。结果表明：0.09?g/100?mL添加量的香豆素更有利于开发阻湿性能好、机械性能高和表面均一的包装材料,具有良好应用前景。     

绿豆改性淀粉可食性复合薄膜的拉伸性能研究

正研究绿豆改性淀粉可食性复合薄膜的拉伸性能,以抗拉强度和断裂伸长率为评价指标,研究改性淀粉用量、壳聚糖-改性淀粉共混液比例、甘油添加量、淀粉糊化温度、干燥温度和干燥时间六个因素对薄膜拉伸性能的影响,得出改性淀粉含量2.0%,壳聚糖-改性淀粉共混液比例6:4,甘油含量2.5%,糊化温度70℃,干燥温度80℃,干燥时间4 h,薄膜的拉伸性能最佳。复合型可食膜是指将多糖、蛋白     

可食性抗菌肽-明胶复合膜的制备及性能表征

为了研究新型的可食性抗菌包装材料,以明胶、甘油、不同浓度的抗菌肽为抗菌剂制备了抗菌肽-明胶复合膜。以光学性能等指标以及傅里叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)和差示扫描量热仪(DSC)对复合膜的性能进行表征。结果表明:添加了抗菌肽的明胶复合膜在250～300 nm波长范围内吸收显著提高,抗菌肽的添加使膜的颜色偏黄,机械性能得到一定的改善,如50 mg/mL的抗菌肽添加量使水蒸气透过率具有一定程度降低(与纯明胶相比降低了17.30%),膜的抗拉强度(TS)和断裂伸长率(EAB)与纯明胶膜相比,分别增加了11.40%和42.90%)。当抗菌肽的添加量为50 mg/mL时,薄膜抗菌能力最为显著(对大肠杆菌和金黄色葡萄球菌的抑菌圈直径分别为14.60 mm和12.30 mm)。FT-IR和SEM显示复合膜有良好的相容性。DSC数据显示抗菌肽对复合膜的热稳定性有一定程度的降低作用。     

壳聚糖对碱性面条品质特性的影响

以玉米淀粉溶液质量为基准,将不同量的壳聚糖(0、0.8%、1.2%、1.6%)加入玉米淀粉溶液中,评价其对碱性面条蒸煮品质、色度、机械性能以及感官品质的影响.结果表明:壳聚糖能够缩短最佳蒸煮时间,减少蒸煮损失,提高蒸煮得率.但是,随着壳聚糖添加量的增加,碱性面条的机械和质地参数、硬度、弹性和整体感官可接受性都有所下降.当壳聚糖添加量为1.2%时,碱性面条具有最高的蒸煮品质、机械性能和感官品质.在壳聚糖添加量超过1.2%后,碱性面条的品质逐渐降低.     

明胶/普鲁兰酶改性淀粉膜的制备与性能研究

研究了普鲁兰酶对淀粉膜性能的影响及明胶对普鲁兰酶改性淀粉膜性能的影响。结果表明:与原淀粉膜相比,普鲁兰酶改性淀粉膜的表面更平滑;膜的热稳定性增大,热封性能增强;抗拉强度、水蒸气透过率和透光率分别增加了75%、18%和35%,断裂伸长率降低了53%。与未添加明胶的酶改性淀粉膜相比,添加明胶后,膜的表面变粗糙;膜的阻水性能与阻光性能增强,热封性能变差。当明胶添加量为10%时,膜的抗拉强度增加了17.6%;当明胶添加量为25%时,膜的断裂伸长率增加了54.3%;在明胶添加量为15%时,膜的热稳定性最大。     

流苏花黄酮类化学成分的分离鉴定

为了提高可食性膜的透明度和阻隔性,制备一种速溶的普鲁兰多糖-明胶可食性膜。将普鲁兰多糖添加到明胶膜中,普鲁兰多糖和明胶的添加质量比为2∶5（PG2）。在此配比下,普鲁兰多糖-明胶可食性膜的抗拉强度是明胶可食性膜的120%,氧气透过率是明胶可食性膜的1/13。可食性膜PG2中普鲁兰多糖和明胶分子间具有较强的氢键作用,并且此时可食性膜具有较好的相容性,因此使可食性膜PG2抗拉强度增强和氧气透过率降低。可食性膜PG2具有较低的氧气透过率（0.15 mL/（m2•d））、较高的抗拉强度（97.21 MPa）和溶水时间（29.5 s）,而且具有不透油和低水蒸气透过率（109.08 g/（m2•d））的性质,因此,可食性膜PG2是适合应用于可食性内包装的材料。     

Combined effects of lemon essential oil and surfactants on physical and structural properties of chitosan films

The aim of this research was to evaluate the effects of lemon essential oil (LO, at 0.5%, 1%, 2% v/v film‐forming solutions) and surfactants (Tween 80 and Span 80 at 0.1% v/v film‐forming solutions) on physical, optical and structural properties of chitosan (CH) films. The films were formed by casting method. Results showed that the incorporation of LO provoked a decrease in water content, water vapour permeability (WVP) and mechanical properties. Less transparency and higher total colour difference were observed in CH–LO composite films. The addition of surfactants significantly increased WVP and solubility in water of CH–LO films. The film containing Tween 80 showed lower mechanical strength and higher transparency. The morphology was different depending on the LO contents and surfactant types used. Tween 80 improved the stability of LO in the film, whereas Span 80 promoted the movement of oil droplets to the film surface.     

蛋清蛋白/苹果多酚提高多糖基可食性包装薄膜性能及在腰果贮藏保鲜中的应用

海藻酸钠（sodium alginate,SA）、κ-卡拉胶（κ-carrageenan,κ-C）具有天然无毒、成膜性好的特点,常被用于制备可食用多糖基包装膜。但多糖薄膜具有亲水性强、机械性能差、抗氧化活性低等缺陷。本实验以SA、κ-C为复合多糖成膜基质,以乳酸钙为交联剂,并添加蛋清蛋白粉（egg white powder,EWP）增强多糖薄膜综合包装性能,添加苹果多酚（apple polyphenol,AP）作为抗氧化剂赋予薄膜抗氧化功能。通过傅里叶变换红外光谱、X射线衍射、扫描电子显微镜、紫外吸收光谱等方法分析各组分基团间相互作用,并对腰果仁进行包装贮藏保鲜实验。结果表明：本研究制备的多糖基可食用包装薄膜具有较好的综合包装性能和突出的抗氧化性能。与SA/κ-C薄膜相比,Ca2＋的交联使可食性薄膜的机械性能、阻隔性能显著提升。在最优添加量下,添加EWP使薄膜断裂延伸率由7.99%提高至20.81%,水蒸气渗透率降低了28.84%,氧气渗透率降低了27.07%;加入AP后,可食性薄膜抗张强度由18.58 MPa提升到30.23 MPa,水蒸气渗透率降低了42.35%,氧气渗透率降低了34.13%,同时薄膜阻光性能显著提升。此外,AP/EWP/SA/κ-C可食性薄膜包装降低了腰果仁贮藏期间的水分活度、水分质量分数、过氧化值和酸价,能有效抑制腰果仁的氧化酸败。结论：研究可为多糖/蛋白质基可食性复合包装薄膜的制备及应用提供参考。     

添加单宁对明胶可食膜性质的影响

如何提高明胶膜的机械性能和阻隔性能,一直以来是可食膜研究领域的重要内容。本文以不同剂量(0 mg/g、10 mg/g、20 mg/g、30 mg/g和40 mg/g)单宁添加于明胶液并以浇注法成膜,然后对膜的理化性质进行分析。研究结果发现单宁有效提高了明胶膜的拉伸强度,但降低了其断裂伸长率;当单宁添加量为30 mg/g(明胶干基)时,其拉伸强度最大(22.10 MPa),断裂延伸率最小(40.12%)。与对照膜相比,单宁的添加降低了复合膜水溶性,水蒸气透过率和氧气透过率。在单宁含量添加范围内,水蒸气透过性最低为1.49×10-11 g/(Pa·s·m);水溶性最低为27.76%,氧气透过率最低为21.63 meg/kg。同时,DSC分析表明单宁提高了明胶膜的热稳定性。FT-IR图谱表明单宁与明胶之间发生了以氢键和疏水键为主的物理交联作用。所以,单宁-明胶复合膜在食品包装方面具有潜在的开发价值。     

羧甲基纤维素强化胶原纤维膜的制备及其性能分析

基于静电相互作用（离子键、范德华力）的蛋白质-多糖聚合现象成为改良可食膜的重要手段。本实验以酸溶胀胶原纤维（正电性）为基料,研究带负电性的羧甲基纤维素（carboxymethyl cellulose,CMC）对胶原纤维膜性能的影响。结果表明：当CMC添加量（以胶原纤维质量计,下同）过多（大于10%）,成膜液发生絮凝甚至分层现象而不能成膜;随着CMC添加量（范围为0%～5.0%）的增加,成膜液ζ-电势显著下降,pH值无明显变化,复合膜表面越来越粗糙,膜厚度增加,透光率显著降低（P＜0.05）;复合膜拉伸强度和杨氏模量随CMC添加量增加而显著增加（P＜0.05）,而断裂延伸率显著降低（P＜0.05）;当CMC添加量达5.0%时,复合膜的水蒸气透过率达到（32.41±0.86）g/（m·s·Pa）,阻氧性与膜溶胀动力学性能显著提高（P＜0.05）;此外,热稳定性分析表明添加CMC能够提高复合膜热稳定性。由此可知,CMC能够通过静电相互作用促进与胶原纤维的结合,提高胶原纤维膜相关机械强度和阻隔性能,从而为可食膜性能提升提供了一种可行手段。     

高直链玉米淀粉-壳聚糖复合膜透气透水性能研究

本文以高直链玉米淀粉(HACS)和壳聚糖(CS)为基本材料,甘油为增塑剂,甲基纤维素(MC)为增强剂制备可食性复合膜,研究了高直链玉米淀粉与壳聚糖的配比、甘油的添加量以及甲基纤维素的添加量对复合膜的透气透水性能的影响.结果表明,HACS:CS为2:1时,膜的CO2透过量和O2透过量最低,水蒸气透过量(WVT)也处于较低...     

Physical properties and antimicrobial activities of a persimmon peel/red algae composite film containing grapefruit seed extract

As a by-product of dried persimmon production, persimmon peel (PP) can be utilized as an edible film base material. In this study, PP/red algae (RA) composite films were prepared, and their physical properties were determined. Among the PP composite films, the 4% PP/1% RA composite film had the best physical properties (7.31 MPa, 8.16%, and 4.99 ng m/m²s Pa for tensile strength, elongation at break, and water vapor permeability, respectively). The optical property of the PP composite film was desirable because the color of the film had an intrinsic persimmon color. In addition, the 4% PP/1% RA composite film containing 1% grapefruit seed extract was prepared as an antimicrobial film. These results suggest that this PP composite film can be applied to food packaging.     

Physico-mechanical and microstructural properties of semolina flour films as influenced by different sorbitol/glycerol concentrations

This study aimed at investigating the physico-mechanical and microstructural properties of a novel edible film based on plasticized semolina flour with different plasticizer (sorbitol/glycerol, 3:1) contents (30, 40, and 50%, w/w). As plasticizer content increased, water vapor and oxygen permeability, tensile strength, and the elastic modulus of the semolina films decreased, while their water solubility, moisture content, and elongation-at-break increased significantly (p < 0.05). Semolina-based films exhibited excellent absorption of ultraviolet light, and the addition of plasticizers improved the optical properties of the resultant films. Fourier-transform infrared spectroscopy showed no significant effect on the structure of the protein. Thermogravimetric analysis also revealed that increasing plasticizer concentration has no remarkable influence on the magnitude of weight loss. Atomic force microscopy images showed that the surface roughness of the films was influenced by plasticizer concentrations. This study demonstrated that semolina flour protein has the potential to prepare edible films.     

Development and characterisation of composite films made of kefiran and starch

In this study, new edible composite films were prepared by blending kefiran with corn starch. Film-forming solutions of different ratios of kefiran to corn starch (100/0, 70/30, 50/50, 30/70) were cast at room temperature. The effects of starch addition on the resulting films’ physical, mechanical and water–vapor permeability (WVP) properties were investigated. Increasing starch content from 0% to 50% (v/v) decreased the WVP of films; however, with further starch addition the WVP increased. Also, this increase in starch content increased the tensile strength and extensibility of the composite films. However, these mechanical properties decreased at higher starch contents. Dynamic mechanical thermal analysis (DMTA) curves showed that addition of starch at all levels increased the glass transition temperature of films. The electron scanning micrograph for the composite film was homogeneous, without signs of phase separation between the components. Thus, it was observed that these two film-forming components were compatible, and that an interaction existed between them.     

Development and Characterization of Soy Protein Isolate Emulsion-Based Edible Films with Added Coconut Oil for Olive Oil Packaging: Barrier,Mechanical, and Thermal Properties

Emulsion-based edible films made of soy protein isolate (SPI), virgin coconut oil (VCO), and soy lecithin (SL) and plasticized with glycerol were prepared using the casting method. The effect of VCO and SL concentrations in SPI films and their in-between interaction were studied through the evaluation of physical (moisture and opacity), mechanical (elongation and tensile strength), water vapor permeability, and thermal properties. The response surface methodology was used to identify the most significant factors in the properties studied. The applicability of SPI emulsion-based films was evaluated as a package for olive oil to be used in small portions. The oxidative stability of the packaged olive oil was monitored by peroxide analyses during 28 days. The incorporation of VCO and SL decreased the moisture content and increased the elongation of the SPI emulsion-based films when compared to the SPI film without these components (control). The opacity of the films increased with the addition of VCO into the protein-based films, but not with the addition of SL or a combination of both constituents. By the other hand, the water vapor permeability was not improved by the incorporation of VCO, SL, or a combination of both. The peroxide value of the olive oil stored in SPI emulsion-based film sachets increased rapidly during the seven first days of storage. After this period, the peroxides increased relatively slow up to 28 days of storage. The peroxide values of the packaged olive oil did not reach the maximum limit recommended by the Codex Alimentarius. Based on these results, this work may be useful for the technological enhancement of emulsion-based films or for food packaging applications.     

Preparation and characterization of kafirin‐quercetin film for packaging cod during cold storage

This study mainly evaluated the physical properties of kafirin‐quercetin (KQ) edible films and their application on the quality of cod fillets during cold storage. The results showed that the addition of quercetin significantly increased mechanical properties of KQ films, while decreased water vapor permeability, water solubility, and transparency. As quercetin was 0.4% (wt/vol), the film had the highest tensile strength (4.96 ± 1.23 MPa), the lowest water vapor permeability (1.08 ± 0.09 g·mm·m^?2·h·KPa^?1) and water solubility (22.02 ± 0.45%). Moreover, compared with the pure kafirin and polythylene films, KQ films could effectively inhibit the cod meat deterioration by restraining the growth of microorganisms and decreasing TVB‐N and TBARs. The KQ_0.4% film was the best to prolong the shelf life of cod fillets during cold storage. Therefore, KQ edible films could be used as a potential food packaging material to protect and retain the quality of aquatic products.