The Experts below are selected from a list of 36 Experts worldwide ranked by ideXlab platform
Ramon Ivo Soares Avelar - One of the best experts on this subject based on the ideXlab platform.
-
convective drying of cape gooseberry fruits effect of pretreatments on kinetics and quality parameters
Lwt - Food Science and Technology, 2017Co-Authors: Joao Renato De Jesus Junqueira, Henrique Martins De Oliveira, Jefferson Luiz Gomes Correa, Ramon Ivo Soares AvelarAbstract:Abstract The effect of physical (fast freezing with liquid nitrogen and slow freezing followed by thawing) and chemical (alkaline solution of ethyl oleate) pretreatments on the kinetics and quality parameters of cape gooseberry (Physalis peruviana) during convective drying (60 °C, 2 m/s) was studied. The influence of the pretreatments on the drying kinetics, shrinkage, rehydration capacity, ascorbic acid retention, water activity, textural profile, and color were evaluated. Five thin-layer equations were evaluated for their ability to predict the drying kinetics, of which the Wang & Singh equation performed best. All of the pretreatments reduced the drying time by reducing the resistance of the Waxy Skin of the gooseberry to mass transfer. The chemical pretreatment promoted the shortest drying time and the highest ascorbic acid retention, rehydration capacity, the best maintenance of texture, as well as the least shrinkage.
M Bustosparra - One of the best experts on this subject based on the ideXlab platform.
-
effect of chemical and physical pretreatments on the convective drying of cape gooseberry fruits physalis peruviana
Journal of Food Engineering, 2013Co-Authors: J E Vasquezparra, C I Ochoamartinez, M BustosparraAbstract:Abstract Drying of cape gooseberry fruits is a slow process because of the low permeability to moisture of the fruit’s Waxy Skin. In this work, the effect of chemical pretreatments (sunflower oil/K 2 CO 3 or olive oil/K 2 CO 3 at 28 °C, and NaOH/olive oil at 96 °C) and physical pretreatments (blanching) to break down the Waxy surface and accelerate moisture diffusion during drying, was assessed. Drying was carried out at 60 °C and 2 m/s air velocity for 10 h. The lowest moisture content (0.27 kg water/kg db), the highest vitamin C content (0.36 mg/g), and the greatest rehydration capacity (1.89) were obtained in fruits pretreated with olive oil (9.48%) and K 2 CO 3 (4.74%). However, the greatest changes in color (Δ E * = 15.05) and chroma (Δ C * = 9.03) were also associated to fruits pretreated with olive oil and K 2 CO 3 . The effective diffusivity of water during drying was 7.37 × 10 −11 m 2 /s in pretreated samples compared with 6.61×10 −11 m 2 /s for untreated samples.
Philip J Back - One of the best experts on this subject based on the ideXlab platform.
-
role of the Waxy Skin layer in moisture loss during dehydration of prunes
Journal of Agricultural and Food Chemistry, 2000Co-Authors: William E Price, Henry T Sabarez, Richard Storey, Philip J BackAbstract:Permeability studies of water through the Skin and flesh of d'Agen plums have been carried out by radiotracer and PGSE NMR techniques as a function of moisture content. The results have shown that the diffusion coefficient of water through the Skin layer increases as the fruit is dried at 70 °C or above. By contrast, the water diffusion through the fruit becomes more hindered as moisture is lost and structural collapse of the cell layers takes place. Values for diffusion coefficients of water at 21 °C through the fruit of 1 × 10-9 m2 s-1 for fresh plums and 2.0 × 10-10 m2 s-1 for fruit dried to 50% moisture content (wet basis) were found. Structural studies using scanning electron microscopy techniques were also performed. These showed that drying induces marked changes to the Waxy Skin layer of the fruit as well as the fruit flesh. These results are discussed in terms of the important role that the plum Skin has in modulating the moisture loss process during dehydration, particularly at early stages of d...
Joao Renato De Jesus Junqueira - One of the best experts on this subject based on the ideXlab platform.
-
convective drying of cape gooseberry fruits effect of pretreatments on kinetics and quality parameters
Lwt - Food Science and Technology, 2017Co-Authors: Joao Renato De Jesus Junqueira, Henrique Martins De Oliveira, Jefferson Luiz Gomes Correa, Ramon Ivo Soares AvelarAbstract:Abstract The effect of physical (fast freezing with liquid nitrogen and slow freezing followed by thawing) and chemical (alkaline solution of ethyl oleate) pretreatments on the kinetics and quality parameters of cape gooseberry (Physalis peruviana) during convective drying (60 °C, 2 m/s) was studied. The influence of the pretreatments on the drying kinetics, shrinkage, rehydration capacity, ascorbic acid retention, water activity, textural profile, and color were evaluated. Five thin-layer equations were evaluated for their ability to predict the drying kinetics, of which the Wang & Singh equation performed best. All of the pretreatments reduced the drying time by reducing the resistance of the Waxy Skin of the gooseberry to mass transfer. The chemical pretreatment promoted the shortest drying time and the highest ascorbic acid retention, rehydration capacity, the best maintenance of texture, as well as the least shrinkage.
Babak Ghanbarzadeh - One of the best experts on this subject based on the ideXlab platform.
-
effect of ultrasound assisted osmotic dehydration pretreatment on drying kinetics and effective moisture diffusivity of mirabelle plum
Journal of Food Processing and Preservation, 2015Co-Authors: Jalal Dehghannya, Rasoul Gorbani, Babak GhanbarzadehAbstract:Conventional air drying of plum is a slow and energy-intensive process because of its Waxy Skin having low permeability to moisture. Ultrasound application in drying foodstuffs aims at reducing the time needed to process and improve the quality characteristics of dried product. In this study, the effect of ultrasound-assisted osmotic dehydration pretreatment on drying kinetics and effective moisture diffusivity of Mirabelle plum during drying was examined. Pretreatments including ultrasonication time at two levels (10 and 30 min), osmotic solution concentration at two levels (50 and 70% sucrose) and immersion time in osmotic solution at four levels (60, 120, 180 and 240 min) were performed. Results showed that application of ultrasound-assisted osmotic dehydration pretreatment can lead to a significant increase in effective moisture diffusivity (from 5.84 × 10−9 to 7.36 × 10−9 m2/s) resulting in a 20% decrease in drying time, and thus involving a higher energy saving and preserving heat labile nutrients. Practical Applications The Mirabelle plum is appreciated by consumers for its health benefits. Drying is among the most popular methods to prolong its shelf life. The Mirabelle plum's Skin consists of an underlying amorphous wax layer adjacent to the cuticle proper, together with crystalline granules of wax protruding from the surface. The Waxy Skin has a low permeability to moisture that increases drying time leading to possible quality deteriorations. Therefore, any pretreatment for plum drying processes that decreases drying time by reducing the initial moisture content and preserves the prune (dried plum) quality is of considerable interest. Methodologies such as ultrasound-assisted osmotic dehydration can be implemented as an alternative pretreatment to reduce drying time and, consequently, processing costs. This study provides information on the effects of operating conditions (sonication time, concentration of osmotic solution and immersion time in the osmotic solution) on drying kinetics, total processing time and effective moisture diffusivity.
-
Shrinkage of Mirabelle Plum during Hot Air Drying as Influenced by Ultrasound-Assisted Osmotic Dehydration
International Journal of Food Properties, 2015Co-Authors: Jalal Dehghannya, Rasoul Gorbani, Babak GhanbarzadehAbstract:Convective drying in hot air is still the most popular method applied to reduce the moisture content of fruits and vegetables. Conventional hot-air drying of Mirabelle plum is considered to be a slow and energy intensive process. This is due to the fact that the Waxy Skin of Mirabelle plum has low permeability to moisture, a fact which results in high shrinkage. The aim of this study was to investigate the effect of ultrasound-assisted osmotic dehydration pretreatment on shrinkage of Mirabelle plum as a function of moisture content with the end goal of optimizing operating conditions that minimize shrinkage of the produce during drying. Results showed that application of ultrasound-assisted osmotic dehydration led to a significant (p < 0.05) decrease in shrinkage (from 76.41 to 64.05%). A linear relation between moisture loss and shrinkage was observed. Results indicated that shrinkage may be easily estimated from changes in moisture content, and independent of the drying rate. Inversely, determination of...
