COMPARISON BETWEEN ANALYTICAL SOLUTIONS OF CRANK AND THE LUMPED APPROACH:CASE STUDY OF INTERNAL AND EXTERNAL MASS TRANSFERS OF DRIED FOOD PRODUCTS
Dehydration is one of the major food processing technologies used to preserve and to increase the shelf-life of food products.During the dehydration process and the rehydration steps,mass transfer within and/or outside the food matrixes play a critical role in the kinetics of desorption and adsorption of water.In the open literature,several attempts were made to simulate or to predict these kinetics by using mathematical models which involve both external and internal mass transfers.The credibility and the validity of these models depend,among others,on the values of these mass transfer parameters.The aim of this contribution is to compare the analytical solutions of Crank and the Lumped method in determining external and internal mass transfers of water adsorption.Mushroom and carrot blanched or not were subjected to freeze-drying or air drying.Dynamic Vapour Sorption (DVS) was used to monitor changes in the weight of the dried samples when placed under different humidity environments.The experimental data obtained by DVS were computed with Matlab by using a non-linear regression approach.The mass transfers were calculated for both analytical solutions of Crank and for the Lumped method.In addition to the comparison between the two approaches,the experimental results obtained in this study were discussed in terms of blanching effect and the impact of drying technologies on the adsorption kinetics.The difference between mushroom and carrot was discussed as well.Next steps will aim at achieving more in this direction by considering numerical approaches and computational fluid dynamic.
Diffusion external/internal mass transfer water adsorption DVS Lumped method Crank solutions drying carrot mushroom blanching
S.Khalloufi A.Mudaliar C.Almeida-Rivera P.Bongers
Structured Materials and Process Science Department,Unilever Research Vlaardingen,Olivier van Noortl Structured Materials and Process Science Department,Unilever Research Vlaardingen,Olivier van Noortl
国际会议
The 18th International Drying Symposium Conference(第十八届国际干燥学术大会(IDS2012))
厦门
英文
1-1
2012-01-11（万方平台首次上网日期，不代表论文的发表时间）