食品低温联合干燥方法及装置的研究

所谓联合干燥是依据食品的特性,将两种或两种以上的干燥方式依照优势互补的原则,分阶段进行干燥的一种复合干燥技术。食品低温联合干燥方法是采用低温（冷风）干燥、冷冻干燥（或真空干燥）、低温（热风）干燥的一项经济合理、产品质地优良的新型联合干燥技术。采用该技术既可以最大限度地保留原有食品的色香味和营养成分,又可以实现以下干燥工艺：低温（冷风）干燥工艺、冷冻干燥工艺、热风干燥工艺、低温联合干燥工艺、真空低温联合干燥工艺。在这些工艺中,与冷冻干燥工艺相比,采用低温联合干燥工艺和真空低温联合干燥工艺在总干燥时间方面要分别缩短50％和70％以上,在单位能耗方面分别降低39．6％和53％左右。     

Spray drying strategy for encapsulation of bioactive peptide powders for food applications

Spray drying is commonly used to manufacture food and dairy powders at industrial scale. Bioactive peptides, as hydrolysis products from various food proteins, are gaining interest due to their biological functionality including immunomodulation, antimicrobial, and antioxidant properties. This article reviews several bioactive peptides/hydrolysates from different food sources, focusing on their processing and final powder characteristics. Additionally, we propose a strategy for encapsulation of food peptide/hydrolysate via spray drying. The identification of suitable drying parameters and/or formulation could help overcome the limitations associated with the current processing of food peptides.     

真空冷冻干燥技术在果蔬类食品加工中的应用现状

目的 为未来冻干技术在果蔬类及更多食品种类中更广泛的运用提供参考。方法 对近些年来真空冷冻干燥技术在果蔬类食品中的应用进行综述,探讨冻干过程中可能存在的问题,以及一些工艺优化措施。结论 尽管真空冷冻干燥技术的用价高昂,但近些年来由于消费者对少加工、高质量食品的需求,该项技术在食品行业中得到了愈发广泛的应用。近年来,预处理及一些创新技术的工艺强化能够有效地应对真空冷冻干燥技术面临的挑战,随着在线监控、品质智能监测等技术的引入,真空冷冻干燥得到了进一步的发展。     

Influence of air dehumidification on water evaporation in a food plant

To reduce the proliferation of bacteria inside food plants, cleaning and disinfection are performed daily following production. These operations are followed by drying during which the drying rate should be as high as possible. This study shows the influence of a dehumidifier on the water mass evolution on surfaces during the drying of a food plant. The temperature, relative humidity and water mass evolution were monitored under two conditions: with and without a dehumidifier. Comparison of the results shows that the drying rate is about 1.5 times higher when a dehumidifier is used. These data were used to develop a simplified heat and mass transfer model allowing the prediction of the temperature and drying rate at different locations. The results can help the manufacturer to evaluate the benefits of a dehumidifier and consider the use of other devices to achieve better airflow distribution or greater heat supply for certain surfaces.     

ZDG—160食品真空冷冻干燥设备

介绍了ＺＤＧ－１６０食品真空冷冻干燥设备及其自动控制系统。该设备可用于生产果蔬、肉类、海产品等食品，营养保健品、中草药等的冷冻干燥产品。该设备系统设计合理紧凑、操作简单、运行可靠、自动化程度高、工艺先进、节能显著。     

真空冷冻干燥高含碘食品原料的实验研究

讨论了海带真空冷冻干燥的工艺，分析了海带冷冻干燥后的成分变化，说明了冷冻干燥海带作为高含碘食品原料很有发展前途。     

食品红外辅助冷冻干燥技术的研究进展

目的概述红外辅助冷冻干燥技术在食品干燥中的研究进展,旨在为红外辅助冷冻干燥技术的选用以及工业化应用提供借鉴和理论支持。方法通过归纳总结国内外的最新研究进展,对红外辅助冷冻干燥技术的机理、红外辐射器波长和温度、食品干燥过程的预测以及对最终品质的影响等进行论述,并且提出改进措施。结果红外辅助冷冻干燥技术的发展潜力巨大,目前研究还处于初级阶段,其中控制红外辐射器温度、波长,监测干燥过程,以及建立适当的动力学模型是实现工业生产规模化的最新研究方向。结论红外辅助冷冻干燥技术可以有效地降低系统能耗,提高产品质量,具有很大的研究价值,新的研究方向具有很大的发展前景。     

Study of the drying process of wetted surfaces under conditions similar to food processing conditions

Two experiments were carried out inside a test room in order to study the drying rate of wetted surfaces under conditions similar to those encountered in food processing plants. In the first experiment, the evaporation of water droplets on a stainless steel plate representing typical equipment was studied under different ambient conditions in the room. In the second experiment, in order to reproduce drying conditions inside a food processing plant, the floor was entirely wetted with water, the water mass evolution was measured when the discharge air was dried by a dehumidifier, and the results were compared with those obtained without using a dehumidifier. Models predicting the evaporation rate in these two experiments were developed and the numerical results show good agreement with the experimental data. Relative humidity was the factor which exerted the greatest influence on the evaporation rate. The drying rate on the stainless steel plate increased five-fold when a dehumidifier was used.     

邻苯二甲酸二丁酯在加工中的变化及膳食暴露评估

目的选取萝卜为研究对象,研究食用加工对萝卜中邻苯二甲酸二丁酯(DBP)残留量及膳食暴露评估的影响。方法采用盆栽种植、模拟餐前加工和液相色谱检测方法,研究漂烫、腌制和干制处理对萝卜中DBP残留及膳食暴露的影响。结果经漂烫、腌制和干制处理后均会对DBP残留量有明显的影响,溶度参数、水分散失和DBP挥发是影响萝卜中DBP含量的3个关键因子。在漂烫加工中,DBP残留量和加工因子随着时间的增加都呈逐渐减小的趋势,消除率为0.96%～45.54%;在腌制加工中,DBP残留量和加工因子随着时间的增加呈先减小后逐渐增加的趋势,消除率为1.36%～44.74%;在干制加工中,DBP残留量和加工因子随着时间的增加呈先增加后逐渐减小的趋势,考虑到干制加工中水分会流失,通过校正含水量后消除率可达82.06%。对DBP残留量进行膳食暴露评估的结果表明,对采用漂烫、腌制和干制等3种加工方式加工后的DBP残留量比用初始值评估值最高可分别降低45.54%,44.73%和24.32%。结论适当的食用加工方式可以有效降低萝卜中DBP的残留量,提高萝卜食用的安全性,而引入加工因子后膳食暴露评估结果会更接近真实值。     

微波对物料微结构的影响

本文介绍了微波加热在陶瓷烧结、木材干燥、食品膨化、超细粉体干燥等过程中对物料微结构的影响。指出，微波加热具有抑制微结构垮塌、膨化食品微结构、抑制纳米粒子团聚等作用。认为微波加热可为纳米粉体干燥和纳米材料制备提供一种潜在处理方法。应当充分研究微细粒子传热传质特性和物料微细粒子介电行为，从而深入认识微波加热对物料微结构的影响。     

罐身补涂烘干机能效等级及测试方法研究

本文提出了罐头食品机械中的罐身补涂烘干机能效指标及其测试方法,对罐身补涂烘干机能效测试结果进行了分析,提出了罐身补涂烘干机能效等级划分的建议.     

食品真空冷冻干燥设备的结构与传热研究

针对目前食品真空冷冻干燥设备的设计、制造技术与结构问题，结合真空冷冻干燥食品的加工生产实际对冷阱与干燥炉配合、加热棚板的传热方式、加热系统设计等进行了研究分析。在此基础上，对于接触导热和辐射传热进行对比实验。研究结果表明，对于加热棚板与铝托盘的传热，辐射传热优于接触导热。     

玻璃化转变温度及其对干燥食品加工贮藏稳定性的影响

在玻璃化转变的相关基础理论上 ,综述了影响玻璃化转变温度的主要因素 ,指出了玻璃化转变温度作为建立在动力控制过程的非平衡态基础上的物理化学参数 ,与水分含量和水分活度两重要指标相结合 ,可以用来解释干燥食品加工贮藏中引起食品腐败变质的各种动力学过程     

超声技术在食品工业中的应用

超声作用的物理机制有热机制、机械机制和空化机制。它能加速质量、热量传递，缩短单元操作时间，提高操作效率；还能促进结晶成核、控制晶粒体粒径分布，改善食品的品质等。超声技术不仅可应用于食品的加工过程，如食品的提取、干燥、过滤、结晶、乳化、灭菌，还可应用于食品体系的检测、分析。文章简要介绍了超声作用的物理机制，重点论述了超声技术在食品加工及食品检测分析中的应用。     

20m^2食品真空冷冻干燥机

简要地介绍了２０ｍ２冷冻干燥机的设计思路，详细阐述了其结构特点及技术参数。实践证明该机用于仪器冷冻干燥能耗低、性能可靠。     

A variance propagation algorithm for stochastic heat and mass transfer problems in food processes

A variance propagation algorithm for stochastic coupled heat and mass transfer problems subjected to first order autoregressive random process boundary conditions was developed. The algorithm is based on the finite element formulation of Luikov's coupled heat and mass transfer equations and involves the numerical solution of coupled Lyapunov and Sylvester matrix differential equations. It offers a cheap alternative to the Monte Carlo method for the computation of the mean value and variance of the temperature and moisture content field. The algorithm is generally applicable and can easily be inserted in any existing finite element code. Also, it can be extended to other types of random processes. The algorithm was applied to analyse the drying of a soybean kernel. Simulation results show that random fluctuations of the process conditions may cause considerable variability of the temperature and the moisture content within the drying soybean kernel. This is an important feature to take into account for the design of a drying process, and for thermal food processes in general. Copyright © 2001 John Wiley & Sons, Ltd.     

Desiccation kinetics of a thin layer of pelletized material

Results are shown of an experimental study concerned with the kinetics of heating and drying in thin layers of wet-pressed food mix. The equation of the desiccation curve is derived by the two ranges method, and an approximate temperature curve is derived by the method in [6].Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 25, No. 2, pp. 294–298, August, 1973.     

芦荟冻干研究

对新鲜芦荟叶进行了真空冷冻干燥处理,并研究了它的物化性能。结果表明,它的主要营养成分得到了很好的保存。与新鲜芦荟相比,干燥芦荟具有很多优点,如易于储存、运输,并能用于某些食品、药物和化装品的添加剂。文中还讨论了它在工业上的其他可能的应用。     

粮食中营养成分标准物质制备技术

介绍粮食中营养成分基体标准物质的制备方法和流程,包括总的原则、成分设计、基体选择、物料采集、物料处理、成分初测、粉碎、筛分烘干过程、均匀性初检、分装、辐照灭菌、真空包装及储存。重点讨论和分析制备过程中应注意的细节以及为了保证均匀性和稳定性所采取的措施。     

利用凤眼莲制作生物质复合包装材料的研究

通过对凤眼莲破碎、热压成型和干燥加工,制备了生物质复合包装材料。 通过分析凤眼莲的纤维特性,并添加胶黏剂等助剂,成功制备了生物质复合包装材料。 研究结果表明,添加胶黏剂等助剂制备的生物质复合包装材料,强度要高于未添加助剂的材料,其助剂适合于生物质复合包装材料的制作。 利用生物质材料的特性,运用精密模压技术加工的生物质复合包装材料,在食品包装、农林牧副产品的包装及运输材料等方面,具有广泛的应用前景,符合绿色化学及可持续发展的战略方针。