食物油炸过程中挥发性成分研究进展

油炸食品的特有风味与食物油炸过程中产生的挥发性成分有关。由于具有较强的挥发性和复杂性,这类物质的鉴定需要有效的气体收集方式和检测分析手段。本文介绍了挥发性成分的常用收集方法、检测技术和安全性分析等,论述了煎炸油直接加热、食物油炸模拟过程和实际食物油炸过程挥发性成分生成情况的研究进展,旨在为食物油炸安全性的提高、煎炸油脂使用期限的评价、油炸食品品质和安全性的改善提供新的研究思路。     

不同油脂对油炸食品中苯并(a)芘含量的影响

以薯条、油条和鸡块为研究对象,探究花生油、大豆油、菜籽油、24°棕榈油、42°棕榈油5种煎炸油对油炸食品中苯并(a)芘含量的影响,以期在今后的油炸烹饪过程中控制油炸食品中苯并(a)芘的含量。采用5种煎炸油176℃油炸薯条(165 s)、油条(150 s)和鸡块(210 s),并用液相色谱法分析不同油脂对油炸食品中苯并(a)芘含量的影响。结果表明:随煎炸批次的增加,不同油脂煎炸食品中苯并(a)芘含量也逐渐增加。花生油煎炸的食品中苯并(a)芘含量最高,薯条为1.64μg/kg,油条为1.73μg/kg,鸡块为1.15μg/kg;42°棕榈油煎炸的食品中苯并(a)芘含量最低,薯条为0.04μg/kg,油条为0.10μg/kg,鸡块为0.05μg/kg。综上所述,42°棕榈油煎炸的食品中苯并(a)芘含量较低,煎炸稳定性较好。     

植物油脂在深度煎炸过程的品质控制

煎炸油在煎炸过程中的变化,即煎炸食发生脱水过程,油脂在深度煎炸过程中发生氧化反应、聚合反应和水解反应。掌握煎炸油周转期、煎炸油重要特性指标如极性物质总值(TPM值)。控制煎炸油和煎炸食物的质量。     

煎炸过程中油脂劣变的影响因素研究

分别对煎炸时间、煎炸方式、煎炸温度、煎炸食材及煎炸油种类对煎炸油极性组分含量和酸值的影响进行研究,分析控制煎炸过程中油脂劣变的有效措施。结果表明：煎炸油的极性组分含量、酸值随煎炸时间的延长而升高,且连续性煎炸优于间歇性煎炸;煎炸温度越高,油脂劣变速度越快,油脂的极性组分含量、酸值升高越快,为保证煎炸食品的卫生质量,延长煎炸油的使用寿命,控制煎炸温度低于200 ℃;不同煎炸食材对煎炸油品质劣变速度的影响大小依次为鱼饼>鸡腿排>薯条;不同煎炸油在煎炸过程中极性组分含量、酸值的变化均不同,多不饱和脂肪酸含量高的大豆油比稻米油、棕榈油更容易发生水解和氧化,稻米油的煎炸周期接近棕榈油。     

基于介电常数的煎炸油废弃指标检测技术

以大豆油和棉籽油为煎炸油,以鸡柳与馕饼为煎炸食品,通过介电常数法测定介电常数、食用油品质检测仪测定极性组分,并利用国标方法测定酸价,通过测定煎炸油样品中介电常数、极性组分和酸价的数据,判断煎炸油中的介电常数与极性组分和酸价是否具有显著相关性。结果表明:在不同煎炸温度和不同煎炸食品的油炸过程中,大豆油和棉籽油介电常数与酸价具有良好的线性相关性,且R2均在0.9以上,证实基于介电常数测定煎炸油极性组分方法的可行性;在不同煎炸温度和不同煎炸食品的油炸过程中,大豆油和棉籽油介电常数与极性组分具有良好的线性相关性,且R2均在0.9以上,证实基于介电常数测定煎炸油酸价方法的可行性。     

煎炸过程的科学管理及煎炸油品质控制

本文论述了煎炸油相关的法律法规及操作规范,比较了现有煎炸油品质现场控制的快速检测技术,分析煎炸过程对煎炸油品质的影响,为餐饮业煎炸过程的科学管理提供指导。     

煎炸不同食物对煎炸油品质的影响

为了探究不同食物对煎炸油劣变程度的影响,将大豆油在180℃条件下煎炸鸡胸肉和土豆,连续煎炸7 d,每天煎炸6 h;分别检测煎炸油的酸值、羰基值、总极性成分含量和脂肪酸组成及含量,分析不同食物对煎炸油品质影响的差异性和相关性,并讨论不同食物成分对煎炸油理化指标影响的原因。结果显示:煎炸鸡胸肉的煎炸油的酸值(KOH)、羰基值、总极性成分含量分别上升到3.14 mg/g、66.69 meq/kg、40.02%,各指标之间呈极显著相关性(P0.01),相关系数大于0.95;煎炸土豆的煎炸油的酸值(KOH)、羰基值、总极性成分含量分别上升到1.48 mg/g、192 meq/kg、47.16%,各指标之间呈极显著相关性(P0.01),相关系数大于0.86;煎炸鸡胸肉的煎炸油饱和脂肪酸、不饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸呈极显著相关性(P0.01),煎炸土豆的煎炸油上述脂肪酸呈显著相关性(P0.05)。煎炸不同食物对煎炸油品质产生不同的影响。     

低场核磁共振技术检测大豆煎炸油品质的研究

煎炸食品一直受到消费者的喜爱,煎炸食品的质量与煎炸油的品质息息相关。传统评价煎炸油品质的理化方法检验费时、操作繁琐、易接触有毒试剂,不能实现在线检测。低场核磁共振技术(LF-NMR)是一种快速、准确、无损的检测方法。以大豆油和添加抗氧化剂大豆油为原料、薯条为煎炸食品,对大豆煎炸油进行理化指标及低场核磁检测。通过研究LF-NMR检测参数S_(21)及t_(2w)与煎炸时间、酸价、羰基价、极性组分含量的相关性,发现S_(21)与2种大豆煎炸油的上述指标均呈正相关、t_(2w)与之均呈负相关,且相关性良好,相关系数在0.905 8~0.994之间。说明利用低场核磁共振技术检测的S_(21)和t_(2w)可以有效地反映大豆煎炸油品质的变化,且不受抗氧化剂的影响。     

油脂饱和度对油炸马铃薯片品质的影响

以玉米油、花生油、大豆油、大豆棕榈调和油、棕榈油5种不同饱和度油脂作为煎炸用油,以马铃薯片为煎炸内容物,于140℃循环煎炸。考察马铃薯片的油脂含量、水分含量、色泽、酥脆性以及感官评分的变化,综合分析油脂饱和度对油炸马铃薯片品质的影响。结果表明:煎炸油脂的饱和度显著影响油炸马铃薯片的品质(p 0.05),随着煎炸油脂饱和度的增加,油炸马铃薯片的油脂含量呈降低的趋势,水分含量呈增加的趋势,L值呈增大的趋势,表明马铃薯片颜色随着煎炸油脂饱和度的增加而越发鲜亮;油炸马铃薯片的酥脆性、感官评分亦随煎炸油脂饱和度的增加呈显著增加的趋势(p 0.05)。由此可知,相对于不饱和度较高的玉米油、花生油、大豆油,饱和度较高的棕榈油更加适合马铃薯片的煎炸。     

油炸食品及其煎炸油卫生质量检测指标关系探讨

该实验在郑州市区53个煎炸点,取油炸食品及其相应煎炸油,按国家标准方法分别对不同煎炸时间油炸食品及其煎炸油的酸价、过氧化值、羰基价三个指标进行检测,调查油炸食品及其煎炸油卫生质量,探讨两者间卫生指标关系。     

Reduction of oil uptake of fried food by coatings: A review

Fried food is popular because of its attractive aroma, colour and taste. However, its high oil content may cause cardiovascular diseases, such as high cholesterol and high blood pressure. Therefore, it is of great significance to reduce the oil uptake of fried food. It is found that water-oil replacement, surfactant theory and the cooling-phase effect are the main mechanisms of oil uptake in fried food. According to these mechanisms, improving the frying technology, changing the frying medium and coating treatment can reduce the amount of oil in fried foods. Among these methods, coating treatment is the most common method to reduce the oil content. Protein coatings usually have better performance than polysaccharide coatings. The performance of protein coatings depends on the type of food and protein. In addition, oil resistance of protein coatings can be improved by adding the plasticiser, combination with other components and cross-linking treatment.     

反复煎炸大豆油的食品安全性及制备O/W乳化剂的研究

目的:开发反复煎炸大豆油的新用途,将其引离食品市场.方法:对大豆油和反复煎炸大豆油的感官性能、酸价、过氧化值、皂化值和羰基价进行理化检验;用气相色谱和红外光谱分析反复煎炸前后大豆油组分及变化情况;皂化反复煎炸大豆油制备O/W乳化剂,通过测定乳化剂的皂化率、表面张力和krafft点评价该乳化剂品质,用制得的乳化剂和反复煎炸大豆油制备O/W乳状液,由乳状液的黏度和稳定性评价乳化效果,结合有关研究判断O/W乳化剂和乳状液的应用价值.结果:反复煎炸大豆油的酸价、过氧化值、皂化值、羰基价和感官性能均不符合大豆油国家标准,不宜继续加工食品,但仍含有大量脂肪酸,具有资源价值.在96℃、反复煎炸大豆油与氢氧化钠的质量比7:1、反应时间130 min的条件下制得的O/W乳化剂具有较高表面活性和较强乳化能力,其乳化反复煎炸大豆油的效果明显好于大豆油在相同条件下制备的乳化剂.用该乳化剂在相同条件下制备O/W乳状液,反复煎炸大豆油乳状液性能优于大豆油乳状液.结论:用反复煎炸大豆油制备O/W乳化剂和乳状液,可消除其食用危害并具应用价值.     

Regulating the use of degraded oil/fat in deep‐fat/oil food frying

During frying, the degradation of oil produces harmful compounds. Improper monitoring of oil‐discard times in restaurants either risks the public health or causes financial losses to industries. Measuring the oil quality is a complex problem and an online sensor is needed. The process of frying reviewed includes moisture, heat and fat/oil transfer, crust formation and various structural, textural and chemical changes in the product, and degradation of frying medium. Some of the European nations and the U.S. have specific regulations against the use of deteriorated frying oils. Due to the absence of a suitable online frying oil quality sensor for restaurant situations, it is difficult to implement any regulation against the use of deteriorated frying oil. Based on various regulations, a model regulation to increase the safety and quality of fried foods is discussed. Background and requirements for developing an online sensor to measure frying oil quality are discussed. Other related areas reviewed in this article are factors affecting oil penetration and absorption by the food, surfactant theory of frying, analytical indices, quick tests and acceptability of frying oil.     

食物油炸过程中丙烯酰胺和杂环胺的形成及控制方法研究进展

食物油炸过程中,来自食物和煎炸油的各种成分会发生强烈的化学反应,产生各种各样的化学产物,最终对油炸食物的食用品质和煎炸油的使用期限产生影响。在这些产物中也存在种类较多且含量不可忽视的有害成分,其中与食品成分相关的主要有丙烯酰胺和杂环胺等伴生危害物。这些有害成分的产生可以通过选择适宜的油炸条件,如煎炸油种类、油炸时间、油炸温度和添加外源抗氧化剂等措施来加以控制。本文综述了近年来研究发现的食物油炸过程中丙烯酰胺和杂环胺的形成途径、危害及控制方法,旨在为寻找抑制食物油炸过程中伴生危害物产生的新方法提供新的思路。     

Application of protein-based edible coatings for fat uptake reduction in deep-fat fried foods with an emphasis on muscle food proteins

BackgroundDeep-fat frying is a common cooking method where fat or oil is used as the heat transfer medium, in direct contact with the food at a temperature above the boiling point of water. During the deep fat frying method, oil not only serves as a heating medium but also absorbs into food, increasing the total fat content. As a result, consumption of deep-fat fried foods has been associated with coronary heart diseases, obesity and type 2 diabetes. Selection of an appropriate food coating before frying may act as a barrier to moisture loss, which is important commercially, and also reduce fat uptake during frying.Scope and approachThis paper succinctly reviews different protein sources for edible coatings and compare them with muscle food proteins which were used in deep-fat fried foods.Key findings and conclusionsProtein-based coatings have been explored as potential coating materials in fat-uptake reduction. Comparatively, proteins are able to form films with better mechanical and barrier properties than polysaccharides. Application of muscle food proteins (myofibrillar proteins) as coatings, which are rich in these proteins, is novel and could be product-friendly for deep-fried muscle foods.     

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。     

食用植物油煎炸过程中的品质变化北大核心CSCD

利用花生油、大豆油、调和油、棕榈油4种食用植物油作为煎炸油对豆腐、裹粉鸡柳、油条3种食材进行煎炸,研究煎炸时间对煎炸油极性组分含量及羰基值的影响,确定煎炸油时间预警点,同时研究了不同煎炸油品种、不同食材对煎炸油极性组分含量的影响。结果表明:极性组分含量、羰基值均与煎炸时间呈正相关(r_(极性组分)=0.809,r_(羰基值)=0.859,P=0.000);煎炸6~11 h煎炸油极性组分含量均值从初始的11.85%增至20.96%,最大值为34.10%,可作为煎炸油质量不达标的时间预警点;煎炸12 h,极性组分含量从低到高依次为花生油、棕榈油、调和油、大豆油,含量分别为21.1%、24.1%、26.8%、27.8%,豆腐、裹粉鸡柳、油条煎炸油中极性组分含量分别为17.7%、25.0%、32.2%;煎炸18 h,极性组分含量增大程度由低到高为棕榈油/调和油、大豆油、花生油,煎炸食材用油为豆腐煎炸油、裹粉鸡柳煎炸油、油条煎炸油。     

《广东省焙烤食品良好生产规范(GMP)》试行的研究

食品GMP起源于美国和FAO/WHO的药品GMP。根据国内外发展状况及其历史背景,针对我国食品GMP与国际发达国家GMP等效性差的状况,经深入研究制订《广东省焙烤食品良好生产规范(GMP)》(以下简称《规范》)。本文采用情境分析与实验研究方法,阐述了《规范》这一保证食品高度安全的良好生产管理体系的基本概念、制订的主要依据、基本内容、内容的特点、设备设施改造与实施要求。     

高温油茶籽油中苯并芘和反油酸产生规律研究

为了探讨高温条件下油茶籽油中苯并芘和反式脂肪酸的形成规律进行了研究。试验测定了不同温度、时间、煎炸不同食材后2种油茶籽油中苯并芘和反油酸以及烟气中苯并芘的含量。结果表明高温条件下,油茶籽油中苯并芘含量未随加热时间延长而明显提高;但反油酸含量随加热时间和温度上升趋势明显。油茶籽油在180℃下煎炸香蕉、面条、瘦肉、豆腐等食材12 h后苯并芘含量大幅上升,且煎炸豆制品上升速度最快;压榨毛油煎炸香蕉和豆腐24 h后油中反油酸仍低于检出限(0.05%),而煎炸面条和瘦肉后,油中反油酸上升明显,分别达到1.9%和0.6%;浸提精炼油中煎炸4种食材后反油酸含量均有显著上升,上升幅度依次是面条豆腐香蕉瘦肉。     

On the Possibility of Nonfat Frying using Molten Glucose

Fried products impose a health concerns due to considerable amount of oil they contain. Production of snack foods with minimal oil content and good management of oil during frying to minimize the production of toxic compounds continue to be challenging aims. This paper aims to investigate the possibility of producing a fat‐free food snack by replacing frying oil with a nonfat medium. Glucose was melted and its temperature was then brought to 185 °C and used to fry potato strips, to obtain a product referred here as glucose fries. The resulting product was compared with French fries prepared conventionally under conditions that resulted in similar final moisture content. The resulting products were also examined for crust formation, texture parameters, color development and glucose content. Stereo microscope images showed that similar crusts were formed in the glucose fries and French fries. Texture parameters were found to be similar for both products at 5 and 2 mm penetration depth. The maximum hardness at 2 mm penetration depth was also similar for both products, but different from cooked potato. The color development that characterized French fries was also observed in glucose fries. The glucose content in glucose fries was found to be twice the content of French fries, which is to be expected because glucose absorbed or adhered to the surface. In conclusion, glucose fries, with similar texture and color characteristics to that of French fries, can be prepared by using a nonfat frying medium.