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This study investigates the effects of different process parameters (sugar dose, sugar size, and ultrasonic treatment time) on the solid osmotic dehydration (SOD) process of jasmine flowers and the physiochemical characteristics of syrup. The kinetics of moisture loss, solute gain, and effective diffusivity during SOD were predicted by fitting the experimental data with the Azuara model, Weibull model, and Fick second law model. The results showed that the high regression coefficient (R2 > 0.9) and low χ2 value represented the suitability of the Azuara model for predicting equilibrium water loss and solid gain and the Weibull model for predicting both moisture and solute fraction in jasmine under different process parameters during SOD. A relatively high sugar dose (120% w/w, fresh jasmine flower basis) and moderate sugar size (6–20 mesh) enhanced the moisture loss and solute uptake during SOD and produced more syrup. Furthermore, the high sugar dose (120% w/w) and small sugar size (40 mesh) enhanced the diffusion of polyphenols and flavonoids in jasmine to syrup. The mass transfer rate and syrup yield were increased, and more polyphenols, flavonoids, and antioxidant components were diffused to the syrup after applying the ultrasonic waves during SOD. Most flavour compounds of jasmine were effectively extracted by SOD under different process parameters, and alcohols (more than 68%) are the main flavour components of syrups, but the amount of major volatile compounds extracted was not affected by SOD process parameters. [ABSTRACT FROM AUTHOR]

Jumbo squid is an important marine resource commercialized in Chile as well as American countries such as Perú, México, and USA. In order to find the best conditions for prevention of squid meat degradation, this study presented the simultaneous application of high hydrostatic pressure and osmotic dehydration (high-pressure impregnation (HPI)) on jumbo squid (Dosidicus gigas) slices. Diffusion coefficients for both components water and solids are improved by the high-pressure processing. The pressures used were 100, 250, and 400 MPa for a 15 g/100 mL salt concentration for time intervals of 30 s. The mathematical expressions used for mass transfer simulations of both water and salt were those corresponding to Newton, Henderson and Pabis, Page, and Weibull models, where the Weibull model presented the best fitted to the experimental data for both components. As to quality parameters studied for texture profile analysis, the treatment at 250 MPa yielded on the samples a minimum hardness, whereas springiness, cohesiveness, and chewiness at 100-, 250-, and 400-MPa treatments presented statistical differences regarding unpressurized samples. The color parameters L* (lightness) increased; however, b* (yellowish) and a* (reddish) parameters decreased when increasing pressure level. This way, samples presented a brighter aspect and a mildly cooked appearance. The results presented in this study could support the potential of high hydrostatic pressure application as a technique novel for other compound impregnation under high pressure. [ABSTRACT FROM AUTHOR]

Osmotic dehydration is a non-thermal process for water removal from foods. The aim of the present study was (i) to investigate the effect of binary (NaCl and water) and ternary (maltodextrin, NaCl, and water) osmotic solutions with or without 0.5% liquid smoke on moisture loss, solids gain, and salt content during osmotic dehydration of beef meat and (ii) to evaluate the microbiological and oxidative stability of the processed meat. Osmotic processing resulted in 8.01-13.15% water loss and 3.53-7.59% solids gain depending on the concentration of the osmotic medium. Liquid smoke did not affect mass transfer phenomena ( P > 0.05), except for the treatment with 25% NaCl. The applied models for the estimation of the apparent coefficients demonstrated a good fit with experimental data. The simplified Fick's equations produced the best results. Osmotic treatment with binary and ternary osmotic solutions reduced total aerobic viable microbial counts ( P > 0.05) of meat during storage at 4 °C for 9 days. Liquid smoke did not affect microbial counts, but it was very effective in inhibiting lipid oxidation during storage. The results demonstrate that osmotic dehydration with the addition of liquid smoke could effectively increase the shelf life of beef meat by at least 2 days. [ABSTRACT FROM AUTHOR]

This study investigated the use of wet and dry osmotic dehydration for modulating the bitter taste of Citrus aurantium peels, imparted by the predominance of flavanones glycosides in their albedo; namely naringin, neohesperidin, and neoeriocitrin. For this purpose, the peels were subjected to dehydration-impregnation by soaking (DIS) in 40°Brix sucrose solution at 25 °C and in 60°Brix sucrose solutions at 25 and 50 °C and to dry osmotic dehydration (DOD) at 25 °C for 6 h. The peels had not shown the immediate dewatering phenomena in the DIS process but rather an imbibition of sucrose solution, reflected in water and sugar gains. Such a tendency has shown to be ascribed to the porous structure of the albedo which fostered the capillary inflow of external liquid. The imbibition was observed during 6 h of treatment in low concentrated sucrose solution whereas in high concentrated ones, it was followed by the dewatering phenomenon thereby inducing an increase of pore volume together with a decrease of cells size. Conversely, in the DOD process, the expected cross transfers of water and sugar were markedly observed. The water was removed from both albedo and flavedo. Indeed, the essential oil cavities exhibited elongation of their shape in line with shrinkage of the peel. The two techniques allowed loss of bitter compounds and gain of sucrose. Nonetheless, The DIS gave rise to higher gain of sucrose and losses of flavanones glycosides than DOD. [ABSTRACT FROM AUTHOR]

The main aim of this work was to evaluate the effect of high-intensity ultrasound (US) on the drying kinetics of orange peel as well as its influence on the microstructural changes induced during drying. Convective drying kinetics of orange peel slabs were carried out at a relative humidity of 26.5 ± 0.9%, 40 °C and 1 m/s with (AIR+US) and without (AIR) ultrasound application. In order to identify the US effect on water transport, drying kinetics were analyzed by taking the diffusion theory into account. Fresh, AIR and AIR+US dried samples were analyzed using Cryo-Scanning Electron Microscopy. Results showed that the drying kinetics of orange peel were significantly improved by US application, which involved a significant ( p < 0.05) improvement of mass transfer coefficient and effective moisture diffusivity. The effects on mass transfer properties were confirmed with microstructural observations. In the cuticle surface of flavedo, the pores were obstructed by the spread of the waxy components, this fact evidencing US effects on the air-solid interfaces. Furthermore, the cells of the albedo were disrupted by US, as it created large intercellular air spaces facilitating water transfer through the tissue. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of microwave pretreatment, usage of methylcellulose, oil temperature, and frying time on mass transfer during deep fat frying of chicken nuggets. Methylcellulose was used in batter and as a coating on product. Microwave with two power densities namely 3.7 and 7.4 W/g was used for reduction of initial moisture content of samples before frying. Frying was performed at three temperatures (150 °C, 170 °C, and 190 °C) and five intervals (0.5, 1, 2, 3, and 4 min) in the sunflower oil. The least oil content was observed when MC was used as a coating layer on non-precooked samples fried at 190 °C. Oil absorption of samples with MC in batter was partially higher compared to control samples. This could be attributed to the rheology of batters. The first-order kinetic model was fitted to moisture and oil content. For determining the correlation between temperature and moisture diffusivity, Arrhenius equation was used. The constant rate for moisture and oil transfer was in the range of 2.2-5 and 0.023-2.67 s, respectively. Effective moisture diffusivity values were between 1.43 × 10 and 3.24 × 10 m/s. Activation energy ranged between 0.71 and 1.71 kJ/mol. [ABSTRACT FROM AUTHOR]

Microwave osmotic dehydration under continuous flow medium spray (MWODS) conditions is an innovative concept with high potential for enhancing moisture loss as well as improving product quality. Quantification of mass transfer kinetics under different processing conditions is important for managing and optimizing the osmotic dehydration process. A response surface methodology was used for evaluating and quantifying the moisture loss and solids gain kinetics of apples during the MWODS process. Experiments were designed according to a central composite rotatable design with all independent variables included at five levels (sucrose concentration, 33.3-66.8°Brix; medium temperature, 33.3-66.8 °C; medium flow rate, 2,120-3,480 ml/min; and medium contact time, 5-55 min). The process responses were moisture loss (ML), solids gain (SG), and weight reduction (WR) and were related to process variables using second-order polynomial regression models. The lack of fit was not significant ( p > 0.05) for any of the developed models. For ML, SG, and WR, the medium contact time was the most significant factor during the MWODS process followed by medium temperature and sucrose concentration. The effect of medium flow rate was only significant with moisture loss and weight reduction. The quantity of ML, SG, or WR achieved over a 30 min treatment time was chosen as the drying rate. These rates were shown to be responsive to the osmotic treatments increasing with sucrose concentration, medium flow rate, and medium temperature. [ABSTRACT FROM AUTHOR]

In this study, the effect of different osmotic solution concentrations (20-60% w/ w of sucrose with 10% w/ w NaCl salt), fruit to solution ratios (1:9-1:3), immersion times (0.5-4 h), and temperatures (15-55°C) on the mass transfer kinetics during osmotic dehydration of melons ( Curcumis melo L.) in ternary solution namely sucrose-salt-water followed by air-drying were investigated. The effective diffusion coefficients for sucrose and water during osmotic dehydration were determined, assuming osmotic dehydration to be governed by Fickian diffusion. The estimated parameters allowed optimizing the system to reduce total processing time. The optimum treatments were with 50% sucrose and 10% NaCl salt concentration, fruit to solution ratio of 1:4 for 1 h at 45°C. Samples non-treated and pre-treated in optimized conditions were dried in a hot-air dryer at 60°C until equilibrium was achieved after 2.5 h. Pre-treatment reduced the air-drying period in up to 6.8 h. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of microwave precooking on mass transfer during deep-fat frying of ostrich meat plates. The influence of microwave power level, frying temperature, and time on mass transfer was determined. Among all treatments, the plates being precooked at 5.23 W/g of microwave power and then deep-fat fried at 135 °C had the minimum fat content. The effective moisture diffusivity ranged between 1.47 × 10 and 4.17 × 10 m/s. Fat transfer rate constant was in the range of 0.024 and 19.708 s. The activation energy obtained from Arrhenius plot for the effective moisture diffusivity ranged between 38.84 and 51.07 kJ/mol. [ABSTRACT FROM AUTHOR]