Conservação de Alimentos Utilizando Fluidização

Abstract

Food preservation is a subject of great relevance to ensure the supply of high-quality food to the population. Various processes are employed for this purpose, among which fluidization stands out. This technique involves the application of a fluid flow to promote the movement of solid particles, generating a turbulent medium characterized by high heat and mass transfer rates. The aim of this study was to conduct a literature review on the application of fluidization as a method for food preservation, with emphasis on drying and freezing processes. The fundamental principles that govern and define the fluidization process were discussed, as well as equations that establish key parameters for the evaluation of processes in porous media, particularly pressure drop. Different types of solid beds were considered: in fixed beds, the material remains static, whereas in fluidized beds, solid particles exhibit intense movement due to fluid flow. Variants of fluidized beds, such as vibro-fluidized beds and spouted beds, were also addressed. In drying, fluidization enables the production of high-quality products with different particle size distributions, due to elevated heat transfer rates that render the process faster and less detrimental to food structure, while also contributing to lower energy consumption compared to slower conventional methods such as freeze-drying or hot-air drying. In freezing, the higher cooling rates favor the formation of smaller ice crystals, which preserve the cellular structure of foods and thereby maintain their quality attributes. In summary, the fluidization technique offers several advantages and applications in food preservation, providing improvements in processing time, energy efficiency, and product quality.