Mass transfer coefficient and the characteristics of coated apples in osmotic dehydrating

Physical and sensory properties of ready to eat apple chips produced by osmo-convective drying

“…Browning index, BI, represents the purity of brown color in the apple flesh due to enzyme activity, which can cause deleterious changes in the appearance and organoleptic properties of the food and therefore is considered as an important parameter associated with the browning of the samples (Jalaee et al 2011). The whitening index on the other hand, WI, corresponds to lesser browning and product discoloration and it is an indicator of enzymatic discoloration (Pathare et al 2012a).…”

Recent Developments in Osmotic Dehydration

“…The results indicated that these coatings improved the efficiency of the osmotic dehydration process, irrespective of the stage of the ripening, increased the water loss, and decreased the solids gain. Jalaee et al (2011) demonstrated that apples coated with carboxyl-methyl cellulose (2%) showed higher moisture loss or solid gain (ML/SG) ratio ( Figure 11.15), as well as improved textural structure of the apple rings.…”

“…Neumann (1972) reported better rehydration characteristics for celery that incorporated of polyhydroxy compounds such as sucrose and glycerol. Pretreatment with a low concentration mixed osmotic solution of salt (3%) and sucrose (6%) caused a considerable increase in rehydration and reduced shrinkage, because of the fact that solutes in this concentration range provide sufficient structural and mechanical strength to withstand the shock during hot air-drying, to prevent cell rupture because of shrinkage, and to improve water uptake during rehydration (Jayaraman et al, 1990). These effects may be attributed to the fact that the solute (salt and sugar) concentration was such that at this level the osmotic pressure difference between the plant tissue and rehydrating solution was not significant, which in turn offered protection against cell damage (Lewicki, 1998a,b).…”

Effect of coating concentration and combined osmotic and hot-air dehydration on some physico-chemical, textural and sensory properties of apple slabs

“…Osmotic dehydration is based on the fact that the immersion of a product in a hypertonic solution with low water activity and high osmotic pressure leads to the replacement of the inner product water with the surrounding solute (JALAEE et al, 2011). During osmotic dehydration three fl ows occur, from which two are of more signifi cance.…”

“…Weibull distribution model was used to investigate the effect of coating concentration on drying kinetics. The results of sensory tests showed that the overall acceptance of samples is increased with decreasing coating concentration, and an appropriate correlation was found between sensory properties and textural parameters.Keywords: coating, osmotic dehydration, air drying, texture profi le analysis, sensory characteristicsOsmotic dehydration is based on the fact that the immersion of a product in a hypertonic solution with low water activity and high osmotic pressure leads to the replacement of the inner product water with the surrounding solute (JALAEE et al, 2011). During osmotic dehydration three fl ows occur, from which two are of more signifi cance.…”