Food Engineering
Sajad Jafarzadeh; Mohsen Azadbakht; Faryal Varasteh; Mohammad Vahedi Torshizi
Abstract
Since persimmon is a pressure-sensitive fruit and it is difficult to store this fruit in warehouses, in this research, an attempt has been made to examine the parameters affecting the reduction of changes in its physical properties. The samples were loaded at 150 and 250 N, three types of foam container ...
Read More
Since persimmon is a pressure-sensitive fruit and it is difficult to store this fruit in warehouses, in this research, an attempt has been made to examine the parameters affecting the reduction of changes in its physical properties. The samples were loaded at 150 and 250 N, three types of foam container packaging with polyolefin film, polyethylene-terephthalate, and ordinary box, and four types of polyamine putrescine coating with concentrations of 1 and 2 mM, distilled water and uncoated. Properties such as Physiological Weight Loss, volume, and the density of persimmon fruit, as well as the firmness of this fruit in the prepost-storage stage were examined. The results showed, the highest firmness was obtained in the treatment of putrescine at a concentration of 1 mM and a foam container with polyethylene film with a value of 6.5 N, which was almost three times the firmness of uncoated fruits. The lowest Physiological Weight Loss, volume, and density were obtained in the same type of coating and packaging. The values of these parameters were 2.458%, 1.82, and 0.833%, respectively, compared to the first day of storage. Overall, the use of polyamine treatment showed a significant effect on changes in the physical properties of persimmon fruit, and foam containers with polyolefin film emerged as the optimal packaging option, resulting in the least amount of change among the different types of packaging used.
Food Engineering
Sajad Jafarzadeh; Mohsen Azadbakht; Faryal Varasteh; Mohammad Vahedi Torshizi
Abstract
Nowadays, the quality of processed fruits or products is defined by a set of physical and chemical properties. In this study, due to the sensitivity of persimmon fruit to pressure, the parameters affecting the color changes of this fruit after pressure have been investigated. Three different coatings ...
Read More
Nowadays, the quality of processed fruits or products is defined by a set of physical and chemical properties. In this study, due to the sensitivity of persimmon fruit to pressure, the parameters affecting the color changes of this fruit after pressure have been investigated. Three different coatings and packing materials and two loading were applied to study the color changes of the samples. Samples were stored in the refrigerator for 25 days. According to the results obtained for the value of L*, b*, Chroma index, Hue index and color changes, the use of 1 mM polyamine coating had a significant effect and caused less change than other coatings. Foil container packaging with polyolefin film has also been better packaged. The lowest percentage reduction for L*, a*, b* , Chroma index and Hue index values was obtained in the 1 mM polyamine with a value of 8.26%, -26.43%, 12.35%, 1.31% and 120.995% respectively, Also the highest value was obtained in the uncoated state with a value of 18.49%, 73.32%, 19.84%, 15.95%, 152.36%. Finally, polyamine coating treatment has a positive effect to prevent the percentage reduction of color parameters of samples. The best coating treatment was polyamine with a concentration of 1 mM
Mohsen Azadbakht; Mohammad Vahedi Torshizi; Fatemeh Noshad; Arash Rokhbin
Abstract
The orange samples were cut into slices with a thickness of 4 mm and treated with ohmic method for 3, 5, and 7 min as ohmic pre-treatment in three voltages 30, 50 and 70 V. Then, they were dried in three replicates using a microwave dryer and at three powers of 90, 360, and 900 W. The statistical analysis ...
Read More
The orange samples were cut into slices with a thickness of 4 mm and treated with ohmic method for 3, 5, and 7 min as ohmic pre-treatment in three voltages 30, 50 and 70 V. Then, they were dried in three replicates using a microwave dryer and at three powers of 90, 360, and 900 W. The statistical analysis results showed that the ohmic time, ohmic voltage and microwave power are significant for the energy and exergy efficiency and specific energy and exergy loss at 1% level. The highest energy and exergy efficiency was observed at 900 W and in the ohmic time of 7 min. The highest energy and exergy efficiency was observed at 59.041% and 47.76%, respectively. The maximum energy loss was seen at 90 W and ohmic time of 3 min. The microwave power, ohmic time, and ohmic voltage were statistically significant for all the parameters (energy and exergy) such that with increasing them, the energy and exergy efficiency increased, while the specific exergy and energy loss decreased.
Mohsen Azadbakht; Mohammad Vahedi Torshizi; Mohammad Javad Mahmoodi
Abstract
This research was aimed to study the effects of loading force and storage period on the physiological characteristic of pears. In this experiment, the pears were subjected to quasi-static loading (wide-edge and thin-edge) and different storage periods (5, 10 and 15 days). The amounts of the fruits’ ...
Read More
This research was aimed to study the effects of loading force and storage period on the physiological characteristic of pears. In this experiment, the pears were subjected to quasi-static loading (wide-edge and thin-edge) and different storage periods (5, 10 and 15 days). The amounts of the fruits’ 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 rates for thin-edge and wide-edge loading in a network with 10 neurons in the hidden layer and a sigmoid activation function were obtained for total phenol content( =0.9539- =0.9865), antioxidant ( =0.9839- =0.9649) and vitamin C ( =0.9758); as for wide-edge loading in a network with 5 neurons in the hidden layer and hyperbolic tangent activation function, the highest R2 rate of vitamin C content was obtained equal to =0.9865. 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.
Mohammad Vahedi Torshizi; Mohsen Azadbakht
Abstract
This study evaluated the effect of different dynamic and static loadings and different storage periods on the firmness of pear fruit. Pear fruit was first segregated into three groups of 27 pear in order to undergo three loadings: static thin-edge compression loading, static wide-edge compression loading ...
Read More
This study evaluated the effect of different dynamic and static loadings and different storage periods on the firmness of pear fruit. Pear fruit was first segregated into three groups of 27 pear in order to undergo three loadings: static thin-edge compression loading, static wide-edge compression loading and dynamic loading. All loaded pears were stored in accordance with three storage period designs: 5-day storage, 10-day storage, and 15-day storage. Following each period, the variations of pear texture were scanned by using the CT-Scan technique as a non-destructive test. Then, the firmness of pear texture was measured using a penetrometer. Data were simulated and evaluated using MLP and RBF artificial neural networks. The results showed that with increasing storage time and loading force , the firmness significantly decreased (1% level) in all three types of loading, In addition, pear texture was destructed under dynamic compression loading in order to compare with other two loadings. Best value artificial neural network for wide edge loading (12 neuron-RBF) was (R2 Wide edge= 0.9738– RMSE Wide edge=0.3419- MAE Wide edge =0.268) and for thin edge loading (4 neuron-RBF) was (R2Thin edge = 0.9946– RMSE Thin edge =0.170977- MAE Thin edge =0.133), also for dynamic loading (8 neuron-RBF) was (R2 Dynamic loading = 0.9933– RMSE Dynamic loading =0.230- MAE Dynamic loading= 0.187).
Mohsen Azadbakht; Mohammad Javad Mahmoodi; Mohammad Vahedi Torshizi
Abstract
Introduction: The study of relationship between physical properties such as mass and volume and other physical properties, such as geometric dimensions, has been the subject of numerous studies by researchers. The fruit size, shape and mass are important in sorting and measuring fruits, and it determines ...
Read More
Introduction: The study of relationship between physical properties such as mass and volume and other physical properties, such as geometric dimensions, has been the subject of numerous studies by researchers. The fruit size, shape and mass are important in sorting and measuring fruits, and it determines that the fruits can be put in boxes of transport or plastic bags by a specific size. Damage to the fruit may be due to various causes, including Impact, pressure and vibration, all of which cause physical damage at moment or at storage time, the amount of damages depends on location of impact, the size and volume. Also, the volume and physical properties of agricultural products are very important for storage. On the other hand, cell damage and forces involved in fruits reason bruising in fruits, which can be controlled by physical properties. Quality assessment is usually carried out using a combination of destructive and non-destructive methods, generally done by the product manufacturers or the first purchasers, and includes the separation of materials based on specific size and weight. Among non-destructive methods used, the use of CT and X-rays, which allow a person to examine bruises at different times in the fruit, is increasing. Due to the fact that mass and volume of fruits for storage, transportation, packaging and etc are of great importance, in this research, the relationship between pear fruit volume and mass with bruise percentage during the storage period was studied using non-destructive CT scan tests due to dynamic loads.
Materials and methods: Firstly, the pendulum and the required masses were made in a workshop. The fruits were placed in the desired position and then the device arm was raised to the desired angle (90°), and in the controlled state of the arm impact the pear. The pendulum had a 200 g and three different attachment masses of 100, 150, and 200 g for knocking. It should be noted that air resistance and friction were neglected through this procedure. In this research, via CT scan, the relationship between mass and volume of pears (Before and after the impact) due impact loading and storage times with bruise was investigated. Before loading and storing, 50 pears were examined using Scan CT and 27 pears with zero bruise percentage were selected, the next chosen pears were subjected to impact loading with a pendulum with three weight of 300, 350 and 400 g and 5, 10 and 15 days storage was used to investigate the effect of impact on pears. Then, after impact and storing, with the use of CT scan in each period of storage, the rate of pear bruise was calculated.
Results and Discussion: The pears volume before impact with the bruise percentage for all three weights had a negative and non-significant correlation and the decrease pear mass percentage with the bruise percentage for all three weights has a positive correlation and pears mass before impact with the bruise percentage for all three weights had a positive and non-significant correlation. Any decrease in pear mass percentage had a positive correlation with caries percentage for all three weights. The correlation test showed that with the increase in pear volume, the bruise percentage was decreased and a direct correlation was found between the decreasing percentage volume and the bruise percentage. –also The effect of 5-day storage duration was found considerable on the bruise percentage subject to the exertion of 350 g and higher impact rates
