PROCESS DEVELOPMENT AND OPTIMIZATION FOR FREEZE-DRYING OF NATURAL ORANGE JUICE

摘要

Freeze-drying is a method of dehydrating frozen materials by a process of sublimation under vacuum, usually for the purpose of preservation. It is a procedure relatively expensive compared to other possible techniques; however, better results may be achieved when freeze-drying is used, especially for thermally sensitive components.rnThe performance of the freeze-drying process is strongly dependent on the adequate operational conditions, and so it is necessary to have extensive analysis of effects of process variables mainly in terms of process time and quality of the obtained product. In the present work, a parametric sensitivity analysis based on the experimental data is presented and a suitable statistical procedure is applied. In order to obtain a product with the market requirements as well as with high productivity and lower costs, process improvement is necessary. Optimization through factorial design using response surface methodology was carried through extensive experimental study. In order to verify the product quality, infrared humidity and water activity were used and it was shown that the process performance might be significantly improved if optimal operating conditions were used.