Modeling the Effects of Osmotic Dehydration Pretreatment Parameters and Lyophilization Kinetics on Mass Transfer and Selected Nutritive Parameters of Peaches
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Date
2022-08-03
Authors
Filipović, Vladimir
Filipović, Jelena 
Lončar, Biljana
Knežević, Violeta
Nićetin, Milica
Vujačić, Vesna
Journal Title
Journal ISSN
Volume Title
Publisher
Periodica Polytechnica Chemical Engineering
Abstract
The effects of the osmodehydration pretreatment parameters on successive lyophilization mass transfer kinetics of the peaches,
dehydrated in the combined dehydration process, were investigated and mathematically modelled. The obtained results showed
the statistically significant effect of osmotic dehydration pretreatment and its parameters on the final dry matter content and water
activity values of the dehydrated peaches. The maximum dry matter content and minimal water activity values of dehydrated peach
samples were 84.60 % and 0.423, respectively, produced in osmodehydration pretreatment in molasses of 80 % concentration,
at 50 °C, during a 5-hour process and subsequent 6-hour lyophilization. With the increase of all osmodehydration pretreatment
parameters it is possible to reduce the duration of the lyophilization process, reducing the high energy demand of the dehydration
method (lyophilization) and substituting it with low energy demanding dehydration method (osmodehydration) without compromising
the quality of the final product, regarding the dry matter content and water activity values. Mathematical models describing the
effect of the duration of the lyophilization on the dry matter content and water activity values of the fresh and dehydrated peaches
were developed. They showed a good correlation between calculated and experimental values, allowing a good prediction of the
investigated responses. In the combined method, protein, sugar, K and Fe content of the dehydrated peach samples were enriched
and further enhanced in prolonged lyophilization stages.
Description
From the presented results, the followings can be concluded:
• Osmotic dehydration pretreatment and each osmotic dehydration pretreatment parameter produced a statistically significant effect on DMC and aw values of the dehydrated peach samples;
• With the increase of osmotic dehydration pretreatment temperature, time, and concentration of the
molasses it is possible to reduce lyophilization pro cess duration, reducing application extent of high
energy demanding dehydration method (lyophiliza tion) and substituting it with low energy demanding
dehydration method (osmotic dehydration), with out compromising final product quality, regarding
obtained DMC and aw values;
• Maximal and minimal obtained DMC and aw values of dehydrated peach samples were 84.60 % and
0.423, respectively, produced in osmotic dehydration pretreatment in molasses of 80 % concentration, at
50 °C, during 5 hour process and subsequent 6-hour lyophilization;All developed mathematical models describing the DMC and aw dependence from lyophilization dura tion showed a good correlation between calculated and experimental values, allowing good prediction of investigated responses within the limits of the
applied technological parameters range of osmotic dehydtaion time, temperature, molasses concentration and lyophilization duration
Keywords
osmodehydration, freeze drying, Prunus persica, sugar beet molasses, mathematical modeling