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In the present study, the functional properties of mechanically deboned chicken meat proteins (MDCM-Ps) were determined at different pH (2, 4, 6, 8 and 12), and film-forming properties were evaluated depending on MDCM-P (2, 3 and 4 %) and glycerol (30, 40 and 50 %) concentrations. The highest solubility, emulsifying and foaming properties were determined at pH 12. MDCM-P solutions showed non-polyelectrolyte behavior and gelation onset temperature was determined at 36 °C. Film-forming properties of MDCM-P showed that the tensile strength decreased, and elongation at break increased as glycerol concentration increased. Films became more transparent with increasing glycerol and decreasing protein concentration, while water vapor permeability increased with increasing glycerol and protein concentration. Water sorption data of films were fitted to the Guggenheim, Anderson, and De Boer model. In general, equilibrium moisture content of films increased as glycerol level increased. Overall, the results showed that MDCM-P could be useful as a new protein source for both food and packaging industries.

Exposure of kumquat fruit to high ambient temperatures during transport leads to excessive deterioration. The aim of this study was to develop an integrated postharvest citrus treatment unit capable of being operated on site at the orchard. The unit consists of rinsing, disinfection (anolyte water), hot water (HWT), surface drying and biocontrol (BT) zones. An energy analysis revealed an electricity consumption of 4.13 and 2.08 kW by the HWT and BT, respectively. The thermal efficiencies of the HWT and BT were 72 % and 87 %, respectively. The total carbon ratio was 0.46 kg CO 2  day −1 with a payback period of 0.91 years. An exposure time of 30 s in anolyte water, hot water at 60 °C + 30 s, 60 °C + 20 s and 53 °C + 30 s and the presence of B13 resulted in low PWL values. A total of 30 s and 60 s of anolyte water; 53 °C; 60 °C + 20 s hot water resulted in firmer fruit.

In this research the application of ultrasound, prior to air-drying, describing the phenomena in two approaches: unripe banana slices immersed in water (hydrated) and vacuum packaged (non-hydrated) were investigated. The results showed two falling rate periods during the air-drying. For the second rate period, an increase of water effective diffusivity due to the “sponge effect” (direct effect of ultrasound) and the microscopic channels formation (indirect effect) was observed. Scanning electron microscopy images showed that untreated dried slices were less porous, characterized by small cavities and high density, while ultrasound pretreated slices resulted in a porous structure with more free volume between cells. An increase in porosity decreased the resistance for diffusion, influencing positively the water effective diffusivity. Moreover, ultrasound produced partial disorder of the crystalline structure within the starch granules, reducing the amount of energy required for gelatinization. Moreover, reduction of resistant starch content was not observed.

The objective of this work was to analyze the relevant process conditions on osmotic dehydration of plums and to determine the diffusion coefficients related to this process. The influence of solution (type and concentration of solute, temperature, fruit/solution ratio) and process time on water loss, water content and solutes gain were studied. Process analysis was performed experimentally by means of a set of 16 duplicate tests and numerically by mathematical modeling of the unsteady-state mass transfer phenomena. Experiments were carried out with glucose and sorbitol solutions (40–60 % w/w), dehydrating plum pieces during 2 h at temperatures of 25 and 40ºC, with fruit/solution ratios of 1/4 and 1/10. For calculating effective diffusion coefficients, a novelty inverse-method was applied, the approximate shape of food-pieces was considered using Finite Elements Method. Calculated diffusion coefficients ranged from 1.13 × 10 −09 to 4.71 × 10 −09 m 2 s −1 and 0.44 × 10 −09 to 3.46 × 10 −09 m 2 s −1 , for water and solutes, respectively.

This article provides numerical study of the solar chimney (SC) assembled with a reversed absorber and packed bed for the indirect-mode solar dryer. The present study was designed to determine the effects of using the SC in three configuration and physical proprieties of the packed (thickness and porosity) on the dynamic and thermal behavior of airflow. The results reveal that (1) using SC without storage material can increase the maximum mass flow rate up to 5%. However, integrating a storage material in the SC can improve the mass flow rate up to 32% during nighttime; (2) the use of a packed bed can decrease the crops temperature fluctuation until about 76% and increase the operating time of the solar dryer up to 12.5 hours rather than 10 hours in the case without packed bed; (3) increasing the porosity from 0.1 to 0.8 can increase the maximum temperature by about 10°C.

The proper efficiency of the tablet-coating process often results in a coating within adequate quality, which might avoid the rejection of the film-coated tablets, minimize the operating expenses and production time. In general, the optimum coating system performance and coating conditions are important for achieving the desirable tablet-coating uniformity and manufacturing reproducibility. In this study, HPMC-aqueous-based tablet film coating successfully conducted in a perforated pan coater for process scale-up using the spray-coating technique. Certain process parameters such as spray rate, inlet air temperature, pan temperature, atomizing pressure as well as pan speed were maintained carefully and the optimum coating quality was achieved with acceptable film performance. At lower initial pan speed, the strength of the coated tablets was remarkably improved and the highest weight gain obtained. The smoothest and uniform film obtained at high spray rate, high pan speed, and low atomizing pressure. The results revealed that the optimum film-coating quality and uniformity achieved at a spray rate of 480 ml/min, atomizing pressure at 5 bar, inlet temperature at 85 to 90 °C, pan temperature at 58 °C, initial pan speed at 1.5 rpm and final pan speed at 4.0 rpm using side-vented pan coater. At initial pan speed of 1.5 rpm, the strength of the coated tablets remarkably improved with minimum edges erosion, which increases the weight gain up to 3.3%w/w.

This paper is concerned with drying kinetics and models of heat pump drying (HPD) of green soybean. Experiments were done for continuous and intermittent drying with intermittency of 1, 3 and 6. Drying rate decreases sharply in continuous HPD process, while circuitously in intermittent HPD process. Peak drying rate values appear in every drying period of intermittent drying and differ a lot because of different intermittent ratios. In addition, various mathematical models were investigated to describe the HPD kinetics of green soybean seeds. Fitting suitability of the experimental data by models was specified as comparing the coefficient of correlation ( R 2 ), mean absolute percentage error ( E MD %), Chi-square Χ 2 and root mean square error ( E RMS ). The page model and 23rd model were found to be the most suitable models in describing the continuous and intermittent drying of green soybeans, respectively.

The desorption isotherms of japonica and indica rice seeds were determined at 15, 25, 35, 45   °C within the water activity range from 0.12 to 0.92 and it was observed that GAB model could accurately describe the desorption behaviors with low values of mean relative error (MRE). The thermodynamic properties of rice seeds were obtained by water desorption isotherms. The moisture content with the minimum integral entropy was considered as the best storage condition where the strongest energetic interaction between water molecular and solid occurred and the optimum seed moisture for storage at 35   °C occurred at 6.02 g water per 100 g of dry matter ( ɑ w of 0.12) for japonica rice seed and 5.28 g water per 100 g of dry matter ( ɑ w of 0.08) for indica rice seed, respectively. The mechanisms of desorption process were determined with integral enthalpy–entropy compensation theory and it was observed that the at low moisture content the desorption process of rice seed was controlled by changes of entropy, whereas the desorption process was considered to be controlled by enthalpy mechanism at high moisture content. It was found that the indica rice seed exhibited a wider water activity range in the minimum integral entropy zone, indicating that indica rice seed was more stable to withstand the different storage conditions compared with japonica rice seed.

In this work, we reported preparation of melatonin-loaded zein nanoparticles using the technique of solution-enhanced dispersion by supercritical CO 2 (SEDS) for prolonging the release of melatonin. The influence of pressure, temperature and the ratio of melatonin and zein on the morphology, the particle size and drug loading was investigated. The release profiles of the melatonin-loaded nanoparticles were evaluated. The sizes of the most particles were less than 100 nm at most conditions examined, and the morphology had three types: rod-like, globule, and filament. The maximum drug loading of 6.9% and encapsulation efficiencies of 80.2% were obtained, respectively, under different conditions. The release speed of the melatonin in the nanoparticles is lower than both the pure one and that in the physical mixture. It displayed a near zero-order release which implied that it could be applied as a potential controlled-release drug.

A simple method called low-temperature vacuum drying (LTVD) was used to produce a novel dehydrated potato flour called raw dehydrated potato flour (RDPF). Preparing RDPF by LTVD at 60°C, 70°C and 80°C in both slice and dice shape was investigated. Potato samples in dice shape are easier dehydrating than in slice shape, the starch granules of RDPF maintain ellipsoid shape as the native potato starch. The best temperature of LTVD to prepare the RDPF is around 70°C according to CIE chromaticity results. Dehydrate at 60°C in dice shape, 88.37% of the trypsin inhibitor activity of the fresh potato is maintained. The Mixolab curve shows that the RDPF has some similar rheological properties of the wheat flour. Protein undenatured, starch ungelatinized, with the high performance of processing properties, RDPF has a number of potential applications in the potato staple food manufacture.