Mathematical modelling of osmotic dehydration kinetics of apple cubes

Fernanda R. Assis, Rui M. S. C. Morais, Alcina M. M. B. Morais*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

52 Citations (Scopus)

Abstract

Apple cubes were osmotically dehydrated at 25, 40 and 60C, using sucrose or sorbitol, and the mass ratio of sample to solution of 1:4 and 1:10, at atmospheric pressure or vacuum pressure of 150 mbar. Six mathematical models were tested to describe the mass transfer kinetics of water loss (WL) and sugar gain (SG). Crank's, Azuara's, Peleg's, Page's and Weibull's models could fit well the experimental data, but the Penetration model resulted in a poor fit. The mass ratio of sample to solution did not have an influence on the mass transfer kinetics at the atmospheric pressure. The increase of temperature and the use of sorbitol as the osmotic agent resulted in an increase of the osmotic process rate at both pressures used. Therefore, sorbitol is a good alternative to sucrose. The vacuum presented a tendency to increase the initial rate of WL. Practical Applications: This work confirms the potential to use sorbitol as an alternative to sucrose as the osmotic agent in OD. Besides presenting low calories, and being less sweet and less cariogenic than sucrose, sorbitol is a prebiotic. It induced an increased process rate, in comparison with sucrose. This is advantageous for a faster OD process. However, the benefit in the process time reduction may not justify the material costs. The mass ratio of sample to solution of 1:4 was identified as an alternative to 1:10 in the OD at the atmospheric pressure, as lower quantities of osmotic solution and, therefore, solute are required to carry out the OD process to the same level of dehydration. This work shows also that simple models, such as Peleg's and Page's, can be used to predict the mass transfer kinetics of WL and SG during OD processes at different conditions.

Original languageEnglish
Article numbere12895
JournalJournal of Food Processing and Preservation
Volume41
Issue number3
DOIs
Publication statusPublished - 30 Jun 2017

Fingerprint

Dive into the research topics of 'Mathematical modelling of osmotic dehydration kinetics of apple cubes'. Together they form a unique fingerprint.

Cite this