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An ohmic heating device was fabricated. For the heating process in three input voltage gradients and three percent weight loss of the sample were selected. During the thermal process, the power consumption was calculated and then using the ratios of pollution in power plants, the amount of NOx, SO2, and CO2 in three Steam, Gas turbine and Combine cycle power plants was calculated. All experiments were performed in three replications using completely random design (CRD) statistical design and the results were analyzed using SAS software. The highest amount of NOx was first in the Gas turbine plant and then in the Combine cycle power plant and Steam power plant, respectively. The amount of SO2 in Heavy gas used in the Steam power plant is more than the other two power plants, and then the highest amount of SO2 is obtained in Gas turbine power plant and finally in Combine cycle power plant. Also, the amount of CO2 in the Combine cycle power plant was less than the other two types of power plants. In general, when the factors of ohmic voltage and weight loss percentage are considered for the ohmic process, natural gas and Combine cycle power plant create the best possible state. [ABSTRACT FROM AUTHOR]

In this research, an ohmic heating system was constructed and applied to the heating process in three input voltage gradients (8.33, 10.83, 13.33 V cm-1) and three weight loss percentages (10%, 20% and 30%) compared to the total weight. Following the heating process, color changes were performed using Image j software that measured factors L*, a*, b *, brown index, chroma, total color difference. All experiments were performed in three replications using factorial analysis and a completely randomized design. The results were analyzed using SAS software, showing that voltage gradient had a meaningful effect on all factors except a*; as for weight loss percentage, all factors were significant, and by increasing the voltage gradient of L*, a* was reduced and the amount of b*, brown index, chroma and total color difference increased during the heating process. The highest value for the color properties of L* is equal to 68.5 and for a* was 6.5 which was obtained at a voltage of 8.33 V. For browning index and b* value, the highest values were 125.4 and 45.2, respectively, which were observed at 13.33 V. For the chroma index and total color difference, the highest values were obtained at exactly the same voltage, which were equal to 43.2 and 19.8. Altogether, the thermal process significantly reduces the brightness and redness of sour orange juice, increasing the amount of yellowness. [ABSTRACT FROM AUTHOR]

The increase in population growth and the demand for food supply and the high percentage of waste production in the food supply chain are among the reasons for increasing attention to the issue of waste management in the world. Due to its huge volume of important nutrients, food waste offers a lot of potential for animal feed production. The goal of this research was to examine the energy and exergy requirements for producing animal feed from food waste using a dryer in two states: reverse flow and non-reverse flow. Hot air is mixed with fresh air in reverse flow but in nonreverse flow fresh air is used. Food waste is collected from kitchen. Food waste was dried at three temperatures of 55°C, 70°C, and 85°C in three times of 90, 150, and 210 min after the dryer was set up in two conditions of return and nonreturn flow. The results showed that the quantity of energy spent is decreased to one-third of the non-return state due to the reuse of output energy. Exergy waste will be decreased by up to 11.5 times. Increasing device efficiency and lowering expenses entails decreasing wasted exergy. Furthermore, the modifications in the stability index mean that the amount of pollutants produced by reverse flow will be lower. [ABSTRACT FROM AUTHOR]

Today, diets rich in fruits and vegetables are highly recommended since they contribute to health. The high deterioration rate of fruits distinguishes them from other crops. This study aimed to evaluate the effects of various storage conditions on some quality attributes of kiwifruit through machine learning (ML) using support vector machine (SVM) models. Kiwifruits were subjected to quasi‐static loading and coated with different coatings, such as grape, date, and mulberry syrups. Then, the coated kiwifruits were stored at humidity levels of 90% and 95% in completely dark and bright environments with a Compact fluorescent lamp (CFL) bulb for 5, 10, and 15 days. Once the storage period had been completed, quality attributes of the kiwifruit, including antioxidant content, phenolic content, total soluble solids (TSS), pH, and firmness were measured. Each test was performed three times. The numerical results were analyzed through an ML approach using an SVM model on MATLAB. To predict the physical properties of kiwifruit using storage conditions and vice versa, it was found that the most accurate SVM model with a linear kernel predicted the weight loss of kiwifruit based on storage conditions, with the coefficient of determination (R2) being 0.54. To predict the biochemical properties using the storage conditions and vice versa, it was found that kiwifruit firmness was most accurately predicted by the SVM model with the Gaussian kernel, with an R2 of 0.70. Moreover, humidity and storage duration were modeled by SVMs with linear kernels, calculating the coefficients of determination to be 0.39 and 0.90, respectively. To predict biochemical properties using physical properties and vice versa, it was observed that the weight loss was more accurately predicted by an SVM with a linear kernel, with an R2‐value of 0.76. Reliable results were not obtained for further research for the other modeled parameters using an SVM approach. Practical Applications: It was found that light was most accurately predicted by the linear SVM. Storage conditions revealed SVM (linear kernel) accurately predicting kiwifruit weight loss. Linear and Gaussian SVMs accurately modeled phenolic and antioxidant content, R2‐values: 0.73 and 0.34, respectively. [ABSTRACT FROM AUTHOR]

Methods such as landfilling, incineration, and aerobic composting of waste are not suitable methods for their management because the production of greenhouse gases and the accumulation of vermin and high cost and the need for a lot of space are the problems of using these methods. The purpose of this study is to select a suitable method with the lowest energy consumption and maximum efficiency in the use of waste. For this purpose, a dryer was designed and fabricated for vegetable and food waste. The most suitable method of waste drying, the method of moving the mass using a helix, was selected. In this food waste dryer, to prevent energy loss, the tank of the device was made of double walls, and ceramic insulation was used between the two walls, and the perforated tank inside the device will cause uniform drying by spreading heat to all parts of the waste. Hot air from the tank outlet was also used. The results of the calculators showed that about 69,000 kJ of energy is needed to remove about 30 kg of moisture from the waste. This high capacity will be able to be used in small and large restaurants and kitchens and for livestock consumption. [ABSTRACT FROM AUTHOR]

In this research, the effect of different parameters of a convective hot air dryer on the mass transfer coefficients of thin‐sliced pears in different drying stages is analytically and experimentally investigated. According to the results, in the first stage of drying which begins from the initial moisture content (MC) of 87–57% in this study, the convective heat transfer coefficient, the inlet air temperature and the initial MC of the product had the highest influence on the mass transfer rate of the drying product. In the second drying stage (from 57 to 27% MC), the structure of internal pore of the fruit, the internal MC and the thickness of the cut layers are the most influencing parameters controlling the mass transfer coefficient of the product. In the third region of drying (from MC of 27% to the final MC), the inlet air temperature had the greatest effect on the rate of mass transfer from the product. In this region of drying, increasing the drying temperature from 50 to 60°C at an airflow velocity of 0.5 m/s, yielded increasing the effective diffusion coefficient from 1.19 × 10−7 to 4.09 × 10−7 m/s2. The results of this study showed that increasing the airflow rate in the third stage of drying reduces the effective mass transfer coefficient. The highest effective diffusion coefficient in the third region of drying for thin‐sliced pears was obtained equal to 6.24 × 10−7 m/s2 for drying temperature of 80°C and airflow velocity of 0.5 m/s. Practical Applications: Pears (Pyrus communis L.) are bell‐shaped fruits that are in the range of green, yellow, brown, red, or a combination of these colors. This useful fruit is rich in potassium, vitamins, and minerals. There are 30 varieties of pears in the world and they are consumed cooked, compote, or raw. The drying process of fruits and vegetables by reducing the moisture of the product, prevents chemical and biochemical spoilage of the product and increases their shelf life. However, some undesirable physical and chemical changes such as discoloration, texture, and nutritional value may also occur during drying, which reduces consumer acceptance. Drying operations usually take place in the final stages and after other operations and lead to the production of the final product. [ABSTRACT FROM AUTHOR]

The current study was aimed to evaluate the physiological properties of pear influenced by two dynamics of loading force and the storage time. In this experiment, the pears were subjected to dynamic loading (300, 350 and 400 g) and different storage periods (5, 10 and 15 d). The amounts of fruit total phenol, antioxidant and Vitamin C contents were evaluated after each storage period. In the present study, multilayer perceptron (MLP) artificial neural network featuring a hidden layer and two activating functions (hyperbolic tangent-sigmoid) and a total number of 5 and 10 neurons in each layer were selected for the loading force and storage period so that the amounts of the total phenol, antioxidants and Vitamin C contents of the fruits could be forecasted. According to the obtained results, the highest R² for dynamic loading in a network with 5 neurons in the hidden layer and a sigmoid activation function were obtained for total phenol content (R² = 0.980), antioxidant (R² = 0.983) and Vitamin C (R² = 0.930). Additionally, considering the value of Epoch and Run for the network, the ability of the neural network to predict total phenol, antioxidant and Vitamin C contents can be used. According to the obtained results, the neural network with these two activation functions possesses an appropriate ability in overlapping and predicting the simulated data based on real data. [ABSTRACT FROM AUTHOR]

This study was conducted considering the high importance of persimmon's chemical properties and the effect of different factors on its variations during storage and maintaining period. This study attempted to investigate some cases such as the effect of compressive loading parameters at 2 levels of 150 N and 250 N, three types of foam container packaging with polyolefin film, polyethylene terephthalate, and ordinary box and four types of putrescine polyamine coating with concentrations of 1 mM and 2 mM, distilled water and uncoated state, the chemical properties of persimmon fruit including the number of antioxidants, total phenol, flavonoids, vitamin C, pH, acidity and dissolved solids. The results showed that the highest content of total phenol and flavonoids was observed in 1 mM putrescine coating and foam container packaging with polyolefin film equal to 109.13 and 6.851 µMQ / 100Gfw and the highest amount of flavonoids and solids in 150 N and 250 N load was equal to 6.97 QMQ / 100Gfw and 19.94 QMQ / 100Gfw, respectively. The highest amount of antioxidants was observed in the foam container with polyolefin film, 1 mM coating and loading force of 150 N. Also, the highest amount of vitamin C was in the coating part for 1 mM putrescine coating with the amount of 14.36 mg / 100gFW and the packaging part in the packaging with foam containers using polyolefin film with the amount of 13.7 mg / 100gFW and the highest value also appeared in the coating treatment with distilled water and 250 N load with the value of 6.83 mg / 100 gFW. In reviewing the pH value, the highest pH value was subject to the uncoated samples and the loading forces of 250 N. It was generally stated that the foam container with polyolefin film and 1 mM putrescine coating created the best values to maintain the qualitative properties. [ABSTRACT FROM AUTHOR]