冷藏食品行业使用的许多食品包装材料都是吸湿的，并且会吸附或解吸水分，这取决于它们通过冷链时所经历的条件。包装吸湿性会对空气相对湿度（RH）、显热比产生显著影响，从而影响产品重量损失、盘管结霜和除霜以及其他表面上的冷凝或结霜等过程。本项目的目标是为制冷工程师提供方法和数据，以估算冷藏设施中食品包装材料的吸湿性对热负荷的贡献。本研究的总体目标是为制冷工程师提供方法和数据，以估算冷藏设施中食品包装材料的吸湿/解吸引起的潜热负荷贡献。具体目标是: 查阅科学和技术文献，了解冷藏设施中包装吸湿的相关机理和理论，并整理和比较之前公布的包装材料吸湿行为数据。对食品行业的北美包装制造商和包装用户进行调查，以创建北美冷冻/冷冻食品行业所用包装材料数量和类型的数据库。审查参考源，以获得并确认代表北美食品储存条件和气候条件的温度和湿度范围。测量重要食品包装材料的吸湿等温线，其相对湿度和温度的适当范围内的数据不存在。在冷链可能经历的条件下，测量代表性食品包装和装载物的吸湿率。 开发并验证用于预测任何特定包装配置和环境条件下吸湿率的通用方法。介绍通过包装以适合制冷设计从业者使用的形式预测因吸水而产生的制冷负荷的方法。

Many food packaging materials used by the refrigerated food industry are hydroscopic and adsorb or desorb water depending on the conditions they experience as they pass through the cold chain. Packaging moisture sorption can have a significant effect on the air relative humidity (RH), the sensible heat ratio and therefore processes such as product weight loss, coil frosting and defrost, and condensation or frosting on other surfaces. The objective of this project was to provide refrigeration engineers with the methodology and data to estimate the heat load contribution due to moisture sorption to/from food packaging materials in refrigerated facilities.The overall aim of this research was to provide refrigeration engineers with the methodology and data to estimate the latent heat load contribution resulting from moisture adsorption/desorption from food packaging materials in refrigerated facilities. The specific objectives were to:Conduct a review of scientific and technical literature to understand the mechanisms and theory related to moisture sorption by packaging in refrigerated facilities and to collate and compare previously published data on the moisture sorption behavior of packaging materials.Conduct a survey of North American packaging manufacturers and packaging users in the food industry to create a database of the amounts and types of packaging materials used within the North American chilled/frozen food industry.Review reference sources to obtain and confirm ranges of temperature and humidity representative of North American food storage conditions and climatic conditions.Measure the moisture sorption isotherms for important food packaging materials for which data over the appropriate ranges of RH and temperature do not exist.Measure the moisture sorption rates for representative food packages and loads under conditions likely to be experienced in the cold chain.Develop and validate a general methodology for the prediction of moisture sorption rates for any specified package configuration and set of environmental conditions.Present the methodology to predict refrigeration loads due to water sorption by packaging in a form suitable for use by refrigeration design practitioners.