高压电场运用于加速食品解冻的研究

在综合论述常用解冻方法优缺点的基础上,提出一种新型的低温解冻技术——高压静电场解冻,介绍了这种技术的国内外发展现状,并且从水的角度初步探讨了解冻机理。     

甘蔗糖厂煮糖真空系统技术现状

分析了煮糖真空系统技术在糖厂节能、节水、减少废水排放等方面的重要性,详细介绍了目前甘蔗糖厂使用的几种真空技术的设计原理及工艺,并对其应用效果进行了对比。     

Sugar crystallization in food products

A review of the recent literature on crystallization of the commercial sugars (fructose, glucose, lactose, and sucrose) is presented. Topics include: NUCLEATION--The formation of the crystalline phase from supersaturated solutions can occur by either a spontaneous or a forced nucleation mechanism. Recent work on the mechanisms, kinetics, and impact of both heterogeneous and secondary (contact) nucleation is discussed. GROWTH--Recent studies on the mechanisms and kinetics of crystal growth will be reviewed. This discussion includes work on the growth rate dispersion exhibited by these sugars. EFFECTS OF IMPURITIES AND ADDITIVES--The presence of impurities and additives (including mixed sugar systems) affects both the nucleation and growth steps. A discussion of the recent work in this area is included. Emphasis is placed on the relationship between these crystallization phenomena and the solution structure for comparison purposes.     

Sustainable edible packaging systems based on active compounds from food processing byproducts: A review

The global food processing industries represent a challenge and a risk to the environment due to the poor handling of residues, which are often discarded as waste without being used in further sidestreams. Although some part of this biomass is utilized, large quantities are, however, still under- or unutilized despite these byproducts being a rich resource of valuable compounds. These biowastes contain biopolymers and other compounds such as proteins, polysaccharides, lipids, pigments, micronutrients, and minerals with good nutritional values and active biological properties with applications in various fields including the development of sustainable food packaging. This review offers an update on the recent advancement of food byproducts recycling and upgrading toward the production of food packaging materials, which could be edible, (bio)degradable, and act as carriers of biobased active agents such as antimicrobials, antioxidants, flavoring additives, and health-promoting compounds. This should be a global initiative to promote the well-being of humans and achieve sustainability while respecting the ecological boundaries of our planet. Edible films and coatings formulations based on biopolymers and active compounds extracted from biowastes offer great opportunities to decrease the devastating overuse of plastic-based packaging. It has become evident that a transition from a fuel-based to a circular bio-based economy is potentially beneficial. Therefore, the exploitation of food discards within the context of a zero-waste biorefinery approach would improve waste management by minimizing its generation, reduce pollution, and provide value-added compounds. Most importantly, the development of edible packaging materials from food byproducts does not compete with food resources, and it also helps decrease our dependency on petroleum-based products. Practical Application Almost 99% of current plastics are petroleum-based, and their continuous use has been devastating to the planet as plastic-derived components have been detected in all trophic levels. Besides, the increasing amounts of food by-products are a socioeconomic and environmental challenge, and halving food loss and waste and turning it into valuable products has become necessary to achieve sustainability and economic circularity. The development of new packaging systems such as edible materials could be one of the solutions to limit the use of persistent plastics. Edible films and coatings by-products-based could also enhance food packaging performance due to their compounds' bioactivities.     

Partition coefficients in food/packaging systems: a review

Food contamination can result from various interactions between food and packaging materials. Migration of volatiles, additives, monomers and oligomers from packaging materials into food or adsorption of volatile compounds from the food by the polymer are important considerations from safety, hygienic and economic points of view. The term 'migration' includes two phenomena (partition and diffusion) that can be important in determining the concentration of contaminants in a food system at any time. An estimation of the partition coefficient, K, in food/packaging systems has been the major objective of numerous different studies. Various parameters can influence K such as temperature, pH, the chemical structure of the migrant, molecular size and structure, fat content, and degrees of crystallinity. Some theoretical approaches such as the quantitative structure-property relationship method could be of interest in the near future.     

Nutritional constituents of pseudo cereals and their potential use in food systems: A review

Consumers are more focused to adopt healthy life styles and appropriate nutritional habits. From the variety of plants which can be potentially used for human nutrition, today fewer and fewer species are used due to elevated risk of health related problems. Results from a number of recent studies have highlighted the need for an improvement in the nutritional quality of cereal based gluten free products. In order to meet the demands of the growing population new food stuffs are being continuously investigated with the aim to improve the diet and conduce to a better health state. At present attention of researchers is more focused towards the exploitation of alternative crops or underutilized species for multifarious uses. Interest in the pseudo cereals has aroused considerably due to their excellent nutritional, phenolic and phytochemical profile and their use in development of gluten free products. Moreover, the amino acid profile and nutritional properties like essential amino acid index, biological value, protein efficiency ratio and nutritional index of pseudo cereals are higher as compared to conventional cereals like wheat rice and maize. Recent studies have indicated that phenolics present in pseudo cereals have several health benefits like prevention and reduction of oxidative stress, anti-cancer, anti-diabetic, anti-inflammatory, anti-hypertensive and prevention of cardiovascular diseases. Therefore, commercialization of these pseudo cereals would help to combat various health related issues, and also the availability of palatable pseudo cereal containing gluten-free products would represent advance towards ensuring an adequate intake of nutrients in subjects with celiac disease.     

Saponins in food—A review

Saponins are surface active sterol or triterpene glycosides. They occur in a large number and a wide variety of plants but only about 28 of these are regularly used as food by man. The more commonly eaten of these are soybeans, chick peas, peanuts and spinach. Many different saponins occur, even within a single plant species. Although they can be readily isolated from plant materials by solvent extraction, it is difficult to isolate individual saponins from the crude mixture and this has rarely been achieved. The presence of saponins in plant extracts is readily indicated by their haemolytic activity and ability to form stable foams in aqueous solution, but for unambiguous identification, it is essential to use thin layer chromatography, with as wide as possible a range of spray reagents. Quantitative analysis of saponins is also best achieved by thin layer chromatography. Older methods, such as that based on haemolytic activity, are not reliable. Full chemical structures of some of the food saponins are known, but for the most part information is at present limited to the structure of their aglycones and the identity of the sugars. Although saponins have antibiotic activity and are toxic to fish and insects, they appear to be practically non-toxic to man, remaining within the gastrointestinal tract. Dietary saponins, either isolated or as saponin-containing food plants, lower plasma cholesterol levels in several mammalian species. They are therefore probably important in human diets to reduce the risk of coronary heart disease.     

Investigating the effect of food trays porosity on the drying process

Improving the dynamics of airflow behavior in the drying system is essential for improving its efficiency. In this study, the impact of the porosity of the plum-filled drying trays on the airflow behavior inside the chamber is investigated. Three configurations of constant porosity (30%, 50%, 70%), and 4 additional configurations of porosity varying linearly along trays 1 and 2 as a function of the x-axis are evaluated. To model the trays as a porous medium, the Power-low mathematical model was used, with the built-in parameters C₀ and C₁ were given experimentally. Both were formed as a subroutine in C++ and integrated into the CFD code, as was done for the integration of unsteady weather parameters. The CFD method used for visualizing and analyzing the airflow behavior in the drying chamber has been previously validated with the experimental result. The obtained results indicate that the average temperature of the drying trays reaches a maximum of 316,91 k at tray 1 for a porosity of 50% and an inlet velocity of 0.1 m/s. For the case of non-uniform trays porosity, it was found that for low air inlet velocity of 0.1 m/s, the velocity difference ΔV is generally low in cases (b) and (d), where it is equal respectively to 0.02 m/s and 0.01 m/s for tray 1, and 0.01 in both cases for tray 2. While for high air inlet velocity of 1 m/s the difference ΔV in both trays reaches 0.17 m/s.     

Superchilling of food: A review

Food preservation is very important for the safety and the reliability of the product. Superchilling as used for preserving foods, has been defined as a process by which the temperature of a food product is lowered to 1-2 °C below the initial freezing point. Fresh and high quality food products are in great demand worldwide. Temperature is a major factor determining the shelf life and quality of food products. Fish and meat are perishable food commodities, where better and more advanced preservation technology is needed. Deterioration of these foods mainly occurs as a result of chemical, enzymatic and bacteriological activities leading to loss of quality and subsequent spoilage. Storing food at superchilling temperature has three distinct advantages: maintaining food freshness, retaining high food quality and suppressing growth of harmful microbes. It can reduce the use of freezing/thawing for production and thereby increase yield, reduce energy, labour and transport costs. The study on the growth mechanism of ice crystals, modelling and computer simulation of foods during superchilling and superchilling storage is needed.     

国内外高压脉冲电场食品杀菌关键技术概况

食品杀菌是食品处理过程中的一个重要环节。高压脉冲电场杀菌因其杀菌时间短、效率高、能耗少等特点在食品灭菌中发挥着越来越重要的作用,高压脉冲发生器是产生高压脉冲电场的主要仪器。综述脉冲电场杀菌机理,高压脉冲发生器的设计原理,并分析国内外各种高压脉冲发生器及其处理室设计的优缺点。     

蛋白质凝胶机理的研究进展

凝胶特性是食品蛋白质的重要功能特性,蛋白质的凝胶行为及其流变性质是形成某些食品独特的质构、感官和风味的决定性因素。长期以来,人们对蛋白质的凝胶行为进行了广泛深入的研究,但对蛋白质凝胶的机理和凝胶动力学还没有完全了解。本文对当前有关蛋白质凝胶的类型、凝胶过程中蛋白质分子构象的变化、形成蛋白质凝胶的主要作用力和凝胶动力学过程的研究进展作了综述。随着现代分析研究技术的进步,对蛋白质凝胶行为的认识也逐渐深入。     

抗氧剂BHT结晶工艺研究

BHT结晶是以乙醇为溶剂，对不同浓度的乙醇，改变溶质与溶剂的物料配比，测定了BHT溶液的出晶点温度，结果表明，在乙醇浓度一定的条件下，出晶点温度随BHT与乙醇配比的增大而降低；而在相同物料配比的条件下，乙醇浓度越低，出晶点温度越高。     

代谢组学方法在食品安全中的应用研究进展

代谢组学方法作为一个新兴的重要研究工具,在药物研发、疾病诊断、植物生理、食品营养学及环境科学等很多领域中得以广泛应用。本文主要介绍代谢组学的研究方法在食品安全分析应用中的最新进展,以推动我国在快速检测检验方面的技术进步和突破,从而达到保障食品安全的目的。      

挤压工艺参数对犬粮产品质量影响的研究

以鸡肉、大米为制备犬粮的主要原料,研究机筒温度、物料水分含量、螺杆转速对挤压膨化犬粮品质指标(蛋白消化率、糊化度)的影响本研究首先以挤压参数为双螺杆挤压机的机筒温度、物料水分含量和螺杆转速进行单因素实验进而根据单因素实验结果进行正交实验,并确定出最佳工艺参数研究得出的三个参数的最佳组合为:机筒温度为80-100-130-140℃;物料水分含量为26％;螺杆转速为150r/min 本研究结果对于应用双螺杆技术控制犬粮生产加工的产品质量方面具有一定的理论指导作用.     

挤压工艺参数对犬粮产品质量影响的研究

以鸡肉、大米为制备犬粮的主要原料,研究机筒温度、物料水分含量、螺杆转速对挤压膨化犬粮品质指标（蛋白消化率、糊化度）的影响。本研究首先以挤压参数为双螺杆挤压机的机筒温度、物料水分含量和螺杆转速进行单因素实验。进而根据单因素实验结果进行正交实验,并确定出最佳工艺参数。研究得出的三个参数的最佳组合为:机筒温度为80-100-130-140℃;物料水分含量为26%;螺杆转速为150r/min。本研究结果对于应用双螺杆技术控制犬粮生产加工的产品质量方面具有一定的理论指导作用。      

Understanding stickiness in sugar-rich food systems: A review of mechanisms,analyses, and solutions of adhesion

Stickinessis an inherent textural property in many sugar-rich foods, which can be problematic to the processing of confectionery products. The adhesion between foods and contact surfaces during processing and consumption has not been well understood in academia or industry. The theories of adhesion were discovered by scientists in the adhesive field of study, some of which can explain the stickiness phenomenon of confections. This work reviewed these theories in the context of sugar-rich foods, followed by a survey on the sensory and instrumental analyses of stickiness. Furthermore, the contributions of ingredients, temperature, compression, and contact surfaces to sugar-rich food adhesion are highlighted.     

麦草制浆碱回收白泥精制填料碳酸钙结晶特征研究

改进传统的苛化方法,添加助剂并控制苛化反应条件,可以得到粒径较均匀的白泥碳酸钙,其形貌为针形和谷粒状,将其用于纸张加填。结果表明:相对于传统的白泥碳酸钙,粒径均匀的针形白泥碳酸钙和谷粒状白泥碳酸钙能更好地用于纸张加填。尤其是针形白泥碳酸钙,对纸张的不透明度和白度有很大的改善作用。