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Recently, the quality of powder product was considered in food industry. Foam mat drying is an economical alternative to spray, drum and freeze-drying for the production of food powders. The high porosity and surface-to-volume ratio of foams during foam-mat drying improve final product quality. In this work, foaming properties of white button mushroom(Agaricusbisporus) were analyzedby response surface methodology. For optimization,xanthan gum (XG)solution range was considered between 0.05–0.3% w/w, mushroom concentration (water: mushroom puree) range was considered 1:0.5– 1:3.5 w/w and whipping time range was considered between 2–8 min. Based on face centered central composite design (CCF),twenty tests were done. Analysis of variance showed that the quadratic modelshaveconsiderable effects on both responses.In this research, the optimized pointwasobtainedat xanthan gum solution 0.2% w/w, mushroom concentration (water:mushroom puree) = 1:2.2 and whipping time= 6.19 minand the predicted values for foam density and drainage volumewere0.56 gcm-3 and 1.8 mL, respectively.At the second step, optimized foam dried at 50, 65 and 80°C and then drying behavior of optimized foam was investigated by different mathematical models. The results indicated that theMidilli model is high accurate model for evaluating the drying behavior of mushroom foam. At the third step, the influence of the drying temperatures on some qualitative characteristics of foam-matdried mushroom powder was investigated. It was found, as the temperature increased, water activity and water binding capacity decreased. Also, Lightness parameter for the temperature of 65°Cwas higher than other temperature.So, white button mushrooms can be processed into powder and used as a functional or nutritional addition in a variety of food products.

One of the important aspects of food drying technology is studying the moisture and temperature changes during the drying process. The temperature changes of the sample are often evaluated by instruments such as thermocouples and thermometers. In this research, infrared thermography was implemented for evaluating the temperature changes during drying process. Experiments were performed for drying air temperature of 60 and 80 oC and temperature changes were measured with T-type thermocouples and infrared thermography. Also, moisture content of apple slice was measured during dying process. The result shows infrared thermography is a good instrument for recording the temperature changes without contact or destroying sample. evaluation drying curves shows, with increasing drying air temperature, heat and mass transfer process increase and drying times decreased consequently.

Shelf life is the amount of time that corresponds to an acceptable reduction in food quality under certain conditions. This feature depends on various intrinsic and environmental factors such as the nature of the food, storage processes, coating and the type of packaging, and it affects the stability of the product. The ability to estimate shelf life is of considerable commercial value, but there is no reliable method for this purpose for fresh pistachios. The aim of this study was to create mathematical models to predict the shelf life of food, using Badamichr   fresh pistachio samples coated with chitosan edible coating in different concentrations (0, 1, and 1.5%) under three atmospheres including ambient atmospheric condition, passive MAP, and active MAP. The shelf life study was performed at 5°C and a multivariate prediction of instrumental and sensorial firmness was performed through kinetic models. In this study, fresh pistachios coated with 1.5% chitosan under active MAP had the highest estimated shelf life (86 days). Also, obtained models were able to estimate the softening time to the end-point of shelf life in different conditions of coating and packaging of fresh pistachios.

Convective air drying is one of the oldest and most popular drying methods. Designing and controlling the convective air drying needs the mathematical description of the moisture transfer during the drying process, known as drying kinetics. Fick’s second law of diffusion can be used for modelling the moisture distribution inside the moist object during drying process.
Mathematical modeling of drying process is a very important tool, as it contributes to understand better moisture distributions inside the product which helps designing, improving and controlling drying operation in the food industry.
Implementation of the partial differential equations subject to the correspondent initial and boundary conditions is one of the main methods of mathematical modeling to describe the physical phenomena such as moisture transfer during drying. In the recent decades, considerable number of research works have been devoted to numerical solution of mass transfer phenomena during convective drying of food products by using the common numerical solution such as FDMs, FEMs and FVMs.
The spectral collocation (pseudospectral) methods is a powerful tool for the numerical solutions of smooth PDEs like mass transfer equations. Pseudospectral methods are able to achieve the high precision with using a small number of discretization points compared to FDMs and FEMs and with low computational time and computer memory.
The objective of present research is to simulate the mass transfer phenomena in one dimension during convective drying of apple slices. The validation of the presented numerical model was done by comparing experimental drying data taken from Kaya et al. (2007) and Zarein et al. (2013). For more confirming the numerical approach, a numerical example with the exact solution is provided and the related errors were evaluated. Estimation of mass transfer coefficients
The convective mass transfer coefficient in the surface of the apple slice was obtained according to the relationship presented by Paitil (1988) and Janjai et al. (2008).
(1)
Estimation of effective moisture diffusivity coefficient
Fick’s second law of diffusion was applied to obtain the effective moisture diffusivity coefficient of the apple slices. The analytical solution of this equation can be written as follows (Crank, 1975): (2)
In this study, we consider the Pseudospectral methods for solving 1D mass transfer equation. In order to develop the model, the following common assumptions are considered: negligible heat changes during drying process, moisture is transferred inside the slices by diffusion, one-dimensional mass transfer in apple slices, non-shrinkage and non-deformation of the slice. In the field of numerical analysis, the main advantage of pseudospectral methods compared to others such as FDMs and FEMs are exponential convergence and sufficient accuracy (Sun et al., 2012). The values of parameters and coefficients of mathematical model are summarized in Table 1. The comparisons between the predicted average moisture content and the experimental data are shown in Fig. 1 & 2. It can be seen, the numerical results are in good agreement with the experimental data. The values of the correlation coefficient and the root mean square error from comparison of numerical result with experimental data taken from Zarein et al. (2013) and Kaya et al. (2007) were 0.9996, 0.0729 and 0.997, 0.1561 respectively. Moreover, the running time for solving 1D mass transfer equations was about 3 seconds. This result is the evident that the presented model is successful for predicting the moisture content history during drying process.
Moreover, by using the considered numerical method the approximate solutions of defined numerical example for different discretizing points was evaluated and the associated error history are shown in Figure 3. It can be seen that the values of errors are very low and about 10-3 and 10-5, that confirms the high accuracy, robustness and efficiency of the suggested numerical approach. Spectral collocation (pseudospectral) method is presented to solve mass transfer equation in one dimensional in during convective drying process approximately. The model was validated by the reported experimental data from convective drying of apple slices. Also, a numerical example, which had an exact solution in a closed form, was provided to illustrate the high accuracy of the proposed method. The results of statistical computations ( and ) and numerical example showed the efficiency, applicability and robustness of the presented approach.

Enzymatic browning and formation of brown pigments are some of the most important problems in preparation of mushroom purees. In this study, the effect of some anti browning agents including sodium metabisulphite, ascorbic acid, and citric acid on the whiteness and foaming properties of mushroom purees was investigated. The results showed that soaking with acids and sodium metabisulphite significantly (05/0p)

Traditional Kurdish cheese is one of the most consuming raw milk cheeses in Iran which there is a few studies accomplished about it. In this study، the effect of ripening period، type of containers (goat skin and plastic containers) and rennet type (traditional rennet and commercial rennet) were evaluated on the physicochemical and microbial characteristics of Kurdish cheese. Physicochemical analysis were involved the measuring of ash، dry matter، pH، fat to dry matter and protein to dry matter ratios and microbial analysis were including total count of mesophilic and termophilic lactobacilli، mesophilic and termophilic lactococci، aerobic psychrotrophic and mesophilic bacteria، entrobacters، entrococci and the total molds and yeasts. The results showed that، both rennet type and containers had no significant effect on microbial load of the cheeses (p>0. 05) whereas the numbers of mesophilic lactobacilli، termophilic lactococci، aerobic psychrotrophic bacteria، entrobacters along with total molds and yeasts have changed during the time (p<0. 05). The amount of dry matter، ash and pH of the cheeses were significantly affected by the containers (p<0. 05) and rennet type also had a significant effect on dry matter، ash and ratio of fat to dry matter (p<0. 05). All the characteristics of cheese were affected by the time of ripening (p<0. 05) except the ratio of protein to dry matter. Finally، according to all results، it seems that cheeses produced by traditional rennet have more nutritional quality than the others manufactured by commercial rennet. Also، using of traditional rennet and goat skin (which traditionally use in the production of Kurdish cheese) had no significant effects on microbial quality of cheeses (p> 0. 05).