油炸食品中可食性膜的应用现状及研究进展

油炸食品因含油量高、易氧化变质、油炸过程中易产生有害物质等,对人体健康造成潜在危害。可食性膜因具有阻隔性、抗氧化性等特性可以有效降低油炸食品含油量,在提高油炸食品品质中具有很好的应用前景。该文主要综述近年来国内外油炸食品中可食性膜的应用及研究进展,对利用可食性膜技术生产出安全、健康、低脂的油炸食品进行展望。     

可食性膜的研究进展

本文从可食性膜的分类及其特点、应用以及发展趋势等几个方面对可食性膜近几年来国内外研究进展进行了综述。     

可食性膜研究进展

可食性膜是一类由脂质，蛋白质和多糖等天然大分子构成的复合膜，它具有阻湿，阻氧，阻油，阻溶质等特性，与化学食品包装薄膜相比，可食性膜安全，无污染，操作性好，国内外纷纷展开专题研究，本文综述了可食性膜研究的最新进展。     

可食性蛋白膜研究进展

传统塑料包装材料引起环境污染问题越来越受到人们关注,其安全性也受到人们质疑,发展新型包装材料,将会是未来方向;蛋白膜以其可生物降解性、可食性、隔油、阻气等性能,正成为国内外研究热点。该文阐述蛋白膜成膜机理、膜的特性及分类,并介绍大豆分离蛋白膜、小麦面筋蛋白膜等可食性蛋白膜国内外研究现状。     

可食性膜制备及改性研究

可食性膜是当前包装材料研究中较为热门课题,并已应用到商品流通许多领域,特别是在食品包装和保鲜领域;该文主要对各类可食性膜制备及膜改性工艺进行综述。     

可食性膜的研究进展

从可食性膜的分类及其特性、影响其特性的因素、安全及健康性论证、在食品中的应用等几方面对可食性膜近年来国内外的研究进行了综述。     

可食性蛋白膜研究进展

可食性蛋白膜以其可生物降解、营养可食、隔油阻气等性能,正在成为国内外研究的热点.越来越多的可食性蛋白膜新技术被应用到食品包装领域.综述可食性蛋白膜的成膜机理、方法、种类、功能特性及其影响因素.     

可食性膜的研究进展

从可食性膜的分类及其特性、影响其特性的因素、安全及健康性论证、在食品中的应用等几方面对可食性膜近年来国内外的研究进行了综述。     

十种可食性食品包装膜

随着科学技术的发展，人民生活水平的提高 ，以及对环境保护日益重视，用可食性包装代替传统塑料包装已成为当前包装行业的一大热门技术。由于可食性包装技术能有效地解决保鲜与环保的问题，因此，目前世界各国都在争相投入资金，加紧开展这方面的研究工作。     

Microencapsulation of Fish Oil by Spray Granulation and Fluid Bed Film Coating

Abstract: The stability of microencapsulated fish oil prepared with 2 production processes, spray granulation (SG) and SG followed by film coating (SG-FC) using a fluid bed equipment, was investigated. In the 1st process, 3 types of fish oil used were based on the ratios of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (10/50, 33/22, and 18/12). Each type was emulsified with soluble soybean polysaccharide (SSPS) and maltodextrin to produce 25% oil powders. In the 2nd process, 15% film coating of hydroxypropyl betacyclodextrin (HPBCD) was applied to the granules from the 1st process. The powder stability against oxidation was examined by measurement of peroxide values (PV) and headspace propanal after storage at room temperature and at 3 to 4 °C for 6 wk. Uncoated powder containing the lowest concentration of PUFA (18/12) was found to be stable during storage at room temperature with maximum PV of 3.98 ± 0.001 meq/kg oil. The PV increased sharply for uncoated powder with higher concentration of omega-3 (in 33/22 and 10/50 fish oils) after 3 wk storage. The PVs were in agreement with the concentration of propanal, and these 2 parameters remained constant for most of the uncoated powders stored at low temperature. Unexpectedly, the outcomes showed that the coated powders had lower stability than uncoated powders as indicated by higher initial PVs; more hydroperoxides were detected as well as increasing propanal concentration. The investigation suggests that the film-coating by HPBCD ineffectively protected fish oil as the coating process might have induced further oxidation; however, SG is a good method for producing fish oil powder and to protect it from oxidation because of the “onion skin” structure of granules produced in this process.     

深度油炸对食用油中反式亚油酸含量的影响

选用我国消费最普遍的压榨大豆油和三级浸提大豆油为试验材料,研究不同大豆油经反复油炸对反式亚油酸含量的影响及其含量随油炸次数增加的变化规律。试验分为2组,反复油炸40次,每炸5次采集1次油样,每组测定3个重复。薯条油炸温度为180～185℃,油炸时间为32 h。试验结果表明,压榨大豆油和三级浸提大豆油中总反式亚油酸含量分别为0.18 g/100 g和0.08 g/100 g,前者极显著高于后者(P=0.001),9-cis,12-trans C18:2和9-trans,12-cis C18:2是2种大豆油中主要的反式亚油酸。深度油炸极显著提高大豆油中反式亚油酸含量(P=0.000),在反复油炸40次后,压榨大豆油和三级浸提大豆油中总反式亚油酸含量分别为1.11 g/100 g和0.68 g/100 g,且前者极显著高于后者(P=0.008)。压榨油反式亚油酸经油炸增加幅度高于三级浸提大豆油。     

姜精油对明胶-CaCO_3 可食膜理化及抑菌特性影响的研究

为开发出一种具有抑菌活性的明胶-碳酸钙可食膜,测定添加0%、1%、3%姜精油的明胶-碳酸钙可食膜的厚度、机械性能、水溶性、水蒸气透过系数、色泽、透明度和透光率、抑菌活性、表面形态微观结构及可食膜在冷藏温度为4℃时对冷鲜肉的保鲜效果等特性。结果表明:加入姜精油后,姜精油与明胶相互作用导致可食膜的外观颜色变暗,抗拉强度、水溶性和水蒸气透过系数均有所降低,而可食膜的厚度、断裂伸长率、抑菌活性均有所提高;原子力显微镜表征可食膜的微观结构及粗糙度结果表明随着姜精油浓度的增加,可食膜表面更粗糙。此外,对冷鲜肉的保鲜实验表明随着姜精油添加量的增加,可食膜对冷鲜肉的保鲜效果越好。综上所述,姜精油添加到明胶-碳酸钙可食膜中开发出的姜精油可食膜在食品包装方面具有潜在的开发价值。     

食用油高温煎炸后的指纹标记研究

利用红外光谱和电子鼻建立快速检测食用油高温煎炸后功能基团变化的方法。结果表明:红外吸收检测发现,油脂加热氧化形成了醛类、酮类吸收峰部分谱区面积发生变化。利用电子鼻检测发现:食用油品加热温度低于150℃成分没有发生明显的变化,超过150℃时,同对照组相比有明显的差异。连续加热超过3h也出现同样的效果。因此,利用红外光谱和电子鼻技术均能鉴别出食用油在高温油炸过程的变化。     

L-阿拉伯糖、增塑剂复合改性鱼皮明胶可食用膜制备工艺研究

以鱼皮明胶为成膜基质,L-阿拉伯糖、甘油和山梨醇为改性剂,采用浇铸法制备可食用膜,以拉伸强度和断裂伸长率为目标优化指标,通过单因素试验及正交试验确定薄膜最佳制备工艺.结果表明:在L-阿拉伯糖和鱼皮明胶质量比2:8、增塑剂(甘油:山梨醇)质量比为2:1、增塑剂浓度20％、水浴温度60℃、水浴时间40 min条件下,可食用...     

Oil Uptake in Deep Fat Frying as Affected by Porosity

The porosity of a restructured potato product ranged from 0.089 to 0.168 after fluctuating subfreezing storage temperatures. A linear relation was found between oil uptake during frying and porosity prior to frying. Bulk and particle density, and porosity were monitored for up to 5 min during deep-fat frying. Particle density increased gradually, bulk density decreased and porosity increased noticeably. After an initial short period, oil uptake correlated linearly with porosity of the fried product. A new term, “net porosity” which excluded the void volume occupied by oil was developed for describing the oil uptake mechanism.     

食用涂膜对油饼含油量和油脂渗透的影响及机理分析

降低含油量是油炸食品健康发展的保证。本研究探讨了甲基纤维素(MC)和大豆分离蛋白(SPI)两种不同种类涂膜物质对油饼含油量和抑油率的影响;通过扫描电镜(SEM)和苏丹红染色后光学显微镜(OM)观察研究MC涂膜对油脂渗透和迁移的影响,并探究MC涂膜降低含油量的机理;通过色差仪和TPA研究了涂膜对油饼感官品质的影响。结果表明:与对照组相比,两种涂膜均能显著降低油饼含油量(p0.05),MC涂膜抑油效果优于SPI,当MC浓度为1%时抑油效果最佳,抑油率为53.77%;表面油和内部油分别降低58.66%和45.43%;通过微观结构分析发现涂膜能够使得油饼表面光滑,减少孔洞,同时能显著降低其渗透深度。这表明,涂膜可以有效降低油饼含油量,使得油饼表面结构致密,抑制油脂的渗透和迁移;且研究表明MC涂膜对样品油炸后色泽及质构影响较小,为进一步生产低油高品质油饼奠定理论基础和技术指导。     

Development and Characterization of an Edible Composite Film Based on Chitosan and Virgin Coconut Oil with Improved Moisture Sorption Properties

An edible composite film was prepared from an emulsion system based on chitosan and virgin coconut oil (VCO). The effect of incorporation of VCO was evaluated at various concentrations and the optimum concentration was chosen based on resultant changes in the properties of the film. Addition of VCO in film forming solution resulted in increase in film thickness and marginal reduction in film transparency. Compatibility of VCO with chitosan was better at lower concentration of VCO as indicated by the microstructure of composite film in scanning electron micrographs. Phase separation was evident at higher level of oil incorporation and the optimal oil/chitosan ratio was determined to be at 0.5 to 1 mL/g chitosan. Furthermore, chemical interaction took place between VCO and chitosan as revealed by Fourier transform infrared spectroscopy data. Even though control chitosan films exhibited superior gas barrier properties, composite film with optimum VCO concentration revealed better mechanical and moisture sorption properties.