Food Technology
Karim Mandahakki; Hamid Hassanpour
Abstract
IntroductionDue to the high rate of respiration, strawberry is prone to water loss, mechanical damage and fungal decay post-harvesting, which may reduce its shelf life (Yan et al., 2019). Food waste is an important global challenge that estimated about 30% of the world's agricultural land. Every year, ...
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IntroductionDue to the high rate of respiration, strawberry is prone to water loss, mechanical damage and fungal decay post-harvesting, which may reduce its shelf life (Yan et al., 2019). Food waste is an important global challenge that estimated about 30% of the world's agricultural land. Every year, about 9.5 million tons of food is lost in the post-harvest phase of agriculture crops (Bishop et al., 2021). Post-harvest storage of strawberry at low temperature without using other combined treatments may reduce its shelf life due to its highly perishable nature. Therefore, in addition to low temperature storage, other post-harvest techniques have also been reported to increase the shelf life of strawberry fruits after harvest. One of these techniques is using chemicals (Kahramanoglu et al., 2019).Glutathione is present in various plant tissues in concentrations of 2 to 3 mM and plays an important role in many cellular processes such as cell differentiation, enzyme regulation, cell signaling and cell death and acts as an antioxidant. (Diaz-Vivancos et al., 2015). During the experiment, spraying GSH on strawberry plants increased the amount of total flavonoids and ascorbic acid in the harvested fruits, and the results showed that the application of GSH can increase the shelf life of strawberries. (Ge et al., 2019). It has been reported that application of glutathione after harvesting okra has reduced browning and prevented its weight loss, which has created a suitable market for it, also GSH has increased the level of total phenol and the activity of ascorbate peroxidase enzyme and reduced the level of ROS and malondialdehyde, which can increase the shelf life of okra in cold storage after harvesting (Li et al., 2023).Materials and MethodsSabrina strawberry fruit was obtained from a commercial greenhouse located in Urmia in the full maturity stage. The fruits were transported to the laboratory of Horticultural Sciences Department of Urmia University, observing the necessary precautions to prevent mechanical damage. The fruits were separated in terms of size and uniformity, so that the fruits were divided into 5 groups of 15, one group as a control group and 4 groups treated with different concentrations of L-glutathione (4, 16, 32 and 64 mM respectively). After drying, the treated fruits were placed in zipped nylon bags and stored for 15 days in a cold room at ± 0.5 °C and a relative humidity of 90-95%. Also, three biological replicates at each time interval were included in the analysis. Samples obtained at each of specified time were placed to evaluate skin color, titratable acidity, soluble solids, taste index, pH, weight loss, total antioxidant capacity, total phenol content, and polyphenol oxidase enzyme activity.Results and DiscussionThe results of variance analysis showed that the effect of GSH treatment after harvesting, the effect of storage and the interaction between them differently affect each of the studied indicators. In terms of color, no significant effect was found. The effect of storage (p≤0.01) and post-harvest treatment (p≤0.05) were significant on TA trait and its highest value was observed in 10 days of storage with 32 mM. In terms of antioxidant capacity (p≤0.05) and PPO activity (p≤0.01), the effect of GSH treatment after harvest was significant, and the highest amount was observed in 16 and 64 mM treatment, respectively. Also, the effect of storage time (p≤0.05) and the effect of GSH treatment after harvesting (p≤0.01) were significant in the trait of total phenol content, and the highest amount was observed in 15 days of storage and 64 mM treatment. However, both the storage (p≤0.01) and the post-harvest GSH treatment (p≤0.05) effects on fruit weight reduction were significant and the lowest weight loss was observed in 5 days of storage and 64 mM treatment. There were no significant changes in indices such as TSS, taste index and pH.ConclusionAccording to the obtained results, the treatment of 64 mM GSH is the best concentration of GSH to increase the shelf life of harvested strawberry fruits in cold storage.Author ContributionsManda-Hakki: conceptualization, data management, financing, research and review, resources, validation, visualization, writing-main draft, Hassanpour: formal analysis, methodology, project management, software, supervision, Writing - review and editingFunding SourcesPart of this project was financially supported by Urmia University.AcknowledgementWe appreciate and thank all those who were with us in this project, especially the officials of Horticulture Laboratory, Faculty of Agriculture, Urmia University.
Food Technology
Aliehsadat Rafaathaghighi; Leila Jafari; Abdolmajid Mirzaalian Dastjerdi; Farzin Abdollahi
Abstract
Introduction
Ziziphus mauritiana, also known as Ber fruit, is a tropical fruit from the Rhamnaceae family with high nutritional value and a short shelf life. Edible coatings the surface of the fruit can play a positive role in increasing its shelf life. The application of alginate (Al), a linear polysaccharide ...
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Introduction
Ziziphus mauritiana, also known as Ber fruit, is a tropical fruit from the Rhamnaceae family with high nutritional value and a short shelf life. Edible coatings the surface of the fruit can play a positive role in increasing its shelf life. The application of alginate (Al), a linear polysaccharide derived from brown seaweed (Macrocystis pyrifera), which has the advantage of moisture retention, and also Shirazi thyme (Zataria multiflora) essential oil (ZEO), which contains antioxidant and antimicrobial compounds, can improve the fruit's characteristics and preserve its quality for a longer period. In recent years, the application of ZEO together with organic coatings in order to enhance the quality characteristics of different fruits during storage has been the focus of researchers. This study aims to investigate the effect of alginate coating and ZEO on the post-harvest and physicochemical characteristics of Ber fruit during storage at 6±1 C˚ and a relative humidity of 90-95%.
Material and Methods
This study was conducted to enhance the shelf life of Ber fruits by treating them with alginate (Al) and Shirazi thyme essential oil (ZEO). Ber fruits at their mature green stage were harvested in 2022 from a commercial orchard in Minab, Hormozgan province. After harvesting, the fruits were transported to the Horticulture Laboratory University of Hormozgan, to apply the treatments. Factors include six treatments (control, Shirazi thyme essential oil 0.5%, Shirazi thyme essential oil 1%, alginate, alginate + Shirazi thyme essential oil 0.5% and alginate + Shirazi thyme essential oil 1%) and five storage periods(zero, 7, 14, 21, 28 days). The treated fruits were then stored at 6±1 C˚, and relative humidity of 90-95% for 28 days. The factorial experiment was conducted as a completely randomized design with four replications, and ten fruits were used in each replication. Fruit parameters such as fruit weight loss, respiration rate, total soluble solids (TSS), organic acid, ascorbic acid, fruit firmness, carotenoids, and chlorophyll content were evaluated. Statistical analysis of data was done using SAS software. Figures were drawn using Excel software.
Results and Discussion
Based on the results of the analysis of variance, the main effects of time and treatment were significant (P<0.01) for all characteristics. Additionally, the interaction effect of treatment and time was significant (P<0.01) for all traits except for ascorbic acid. Comparisons of means showed that all treatments, maintained fruit quality compared to the control. The Al + ZEO treatment had a significant effect on reducing respiration rate. This combined treatment reduced weight loss, decay percentage, and fruit softening while slowing down the increase in TSS. The alginate coating and Shirazi thyme essential oil delayed ripening and subsequent fruit softening by reducing ethylene activity. Furthermore, the coated fruits had higher levels of ascorbic acid compared to the untreated fruits. These coatings are impermeable to water vapor and create a saturated atmosphere, preventing fruit evaporation and wrinkling, thus delaying ripening. The use of essential oils in the form of a semi-permeable layer also reduces respiration and surface transpiration by inhibiting the movement of oxygen, carbon dioxide, and moisture, playing a positive role in preserving fruit quality.
Conclusion
The aim of this study was to investigate the effect of alginate coating and Shirazi thyme essential oil on the post-harvest and physicochemical characteristics, as well as the shelf life of Ber fruit. The results clearly indicated the enhancement of fruit quality using edible coatings compared to the control. The combination of Al + ZEO (0.5%) had significantly positive effects on preserving the postharvest quality of Ber fruit. In fact, by creating a semi-permeable coating on the surface of the fruit, thyme essential oil and alginate lead to limiting the fruit respiration and metabolism and fungi growth, thus delaying the ripening process, increasing TSS and ascorbic acid and total acidity. According to these results, to reduce post- harvest losses and increase productivity of fruit, the use of 0.5% Shirazi thyme essential oil in combination with alginate coating is recommended due to its beneficial effects on the appearance and physicochemical characteristics of Ber fruit during storage.
Acknowledgement
The authors of this article express their gratitude and appreciation for the financial support from the Hormozgan Science and Technology Park and the University of Hormozgan.
Food Technology
Behshad Tahani; Babak Beheshti; Mohsen Heidarisoltanabadi; Ehsan Hekmatian
Abstract
Introduction
Isfahan province is considered to be one of the top ten producing provinces of apple orchards with an area of 17,274 hectares and a production of 120,000 tons of apple. Determining the quality parameters of agricultural products requires the use of various methods, which are different according ...
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Introduction
Isfahan province is considered to be one of the top ten producing provinces of apple orchards with an area of 17,274 hectares and a production of 120,000 tons of apple. Determining the quality parameters of agricultural products requires the use of various methods, which are different according to the nature and characteristics of each product. The two main categories for dividing these methods include analytical (objective) methods and sensory (intrinsic) methods. Both qualitative assessment methods can be used in destructive and non-destructive ways. Apple is one of the fruits that can be stored for a relatively long time. Physiological changes during the storage period are inevitable and cause change to some quality characteristics of the fruit, such as firmness, moisture content, density, pH, and soluble solids. Using the methods of determining and extracting the quality characteristics of fruit during storage and monitoring the changes created, provides a suitable criterion for selecting and preparing the necessary conditions for storage and storage at the disposal of users and producers. X-ray imaging technique is among the methods used and computed tomography, which is now well-known in evaluation of various agricultural commodities and food quality. X-rays are electromagnetic waves with a short wavelength (0.01 to 10 nm) and high energy (from 120 electron volts to 120 kilo electron volts) that can penetrate many materials.
Materials and Methods
In order to determine the relationship between the physicochemical properties and the CT number of Golden Delicious apples, 280 Golden Delicious apples were collected from an orchard located in Semirom city of Isfahan province and stored in a cold room at 0 and 4 ºC and a humidity of 85±5%. These apples were harvested and collected from several trees after the fruit ripened completely. The weight and volume of apples were randomly selected based on the apples on the trees. The samples of stored apples were examined in 4 stages and based on the duration of storage on zero (the beginning of storage), 45, 90 and 135 days.. These tests included non-destructive tests of CT scan imaging and destructive tests to extract the physicochemical properties of apples, including CT number, pH, firmness, moisture, density, and soluble solids. In order to prepare CT scan images of apple samples (non-destructive X-ray test), a GE Healthcare multi-slice CT scan machine model 5122080-12 with 80 kV and 10 mA was used in the CT scan center of Al-Zahra Hospital in Isfahan. Moisture content was determined by weighing the samples and recording their moisture changes before and after drying in the oven at 105 ºC s for 24 hours. Total soluble solids were measured by refractometer device and reported as Brix degree. In order to measure the density of fruits, the weight and volume of each fruit was recorded. A digital pH meter was used to measure the pH of fruit. Penetrometer device was used to measure the firmness of apples. At the end, with the specified values, Pearson correlation coefficients between CT number and other physicochemical properties were determined. Also, by plotting the mentioned values, the most suitable regression equations with the highest coefficients of determination were obtained.
Results and Discussion
Based on the results, the average value of CT number, pH, firmness, moisture, density and total soluble solid of apple at two temperatures of zero and 4 ºC were -115.02 and -166.86, 3.85 and 3.86, 76 37.36 and 33.36 N, 0.82 and 0.80%, 0.76 and 0.72 g/cm3 and 15.30 and 15.79% Brix, respectively. The results showed that the CT number has a negative linear correlation with pH and total soluble solid and a positive linear correlation with the properties of apple firmness, moisture and fruit density. Based on the results, at two storage temperatures of 0 and 4 ºC, the coefficients of determination (R2) obtained from the linear regression model of CT number with pH levels of 0.75 and 0.55, apple firmness 0.32 and 0.57, moisture content 0.78 and 0.85, fruit density 0.82 and 0.84 and total soluble solid 0.85 and 0.62 were obtained.
Conclusion
These results shown that the non-destructive test of X-ray imaging can be used with a suitable approximation to determine some quality properties of apple products.
Food Chemistry
Dara Rezakhani; Abdolmajid Mirzaalian Dastjerdi; Somaye Rastegar
Abstract
The sapodilla fruit has a limited shelf life due to its perishability and rapid moisture loss. The application of edible coatings has attracted much interest because they are effective in prolonging the shelf life of fruits. This study aims to evaluate the effectiveness of an edible coating made from ...
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The sapodilla fruit has a limited shelf life due to its perishability and rapid moisture loss. The application of edible coatings has attracted much interest because they are effective in prolonging the shelf life of fruits. This study aims to evaluate the effectiveness of an edible coating made from xanthan gum (XG) (0.1% and 0.2%) combined with oleic acid (Ol) (1%) in prolonging the shelf life of sapodilla fruit at 8 ± 1 οc and a relative humidity (RH) of 85-90%. Weight loss was significantly reduced in the treated fruits, with the minimum weight loss observed in the Xan 0.2% + Ol treatment. Except for the Ol treatment, the other treatments showed a higher level of firmness compared to the control. At the end of the experiment, the treatments significantly reduced fruit respiration. The treated fruits also showed significantly increased antioxidant capacity and higher levels of ascorbic acid compared to the control. The lowest TSS (22.8%) level was noted in the Xan 0.2 + Ol treatment. Moreover, the results showed that fruit treated with Xan 0.1% + Ol coating exhibited higher activity in the superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) enzymes compared to the fruit treated with Xan 0.2 + Ol coating and the control samples. In general, fruits treated with Xan 0.2 + Ol and Xan 0.1% + Ol demonstrated the highest overall quality compared to the control and other treatments. Therefore, the application of these treatments is recommended for maintaining the quality of sapodilla fruit.
Food Chemistry
Sakineh Molaei Mohammad Abadi; Somaye Rastegar
Abstract
This study aimed to determine the effects of preharvest spraying of melatonin and postharvest immersion in xanthan gum on the quality and postharvest performance of Orlando tangelo mandarin fruits. After selecting suitable and uniform trees, melatonin foliar spraying was performed at three different ...
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This study aimed to determine the effects of preharvest spraying of melatonin and postharvest immersion in xanthan gum on the quality and postharvest performance of Orlando tangelo mandarin fruits. After selecting suitable and uniform trees, melatonin foliar spraying was performed at three different concentrations: 0,100 μM, and 200 μM. Foliar spraying was performed one month before harvest and was repeated three times at weekly intervals. Furthermore, the fruits were immersed in two different concentrations of xanthan gum (0.1% and 0.2%) postharvest, these fruits were stored in a cold room at 5 ± 1 °C. Evaluation of fruit characteristics was carried out at the time of harvest and after 45 and 90 days of cold storage. The results showed that foliar spraying of melatonin at a concentration of 100 μM showed the highest weight and pulp of the fruit. Furthermore, melatonin treatment resulted in higher levels of ascorbic acid and increased fruit acidity compared to the control. During storage, fruits treated with melatonin and xanthan coatings showed better quality than those of the control. At the end of the experiment, the lowest weight loss was observed in fruits treated with 200 μM melatonin + 0.1% xanthan. The highest ascorbic acid content was observed in the 100 μM melatonin +0.1% xanthan. The maximum antioxidant activity was observed in 100 μM and 200 μM +0.1% xanthan and also 100 μM melatonin alone. In general, the findings suggest that preharvest foliar spraying and the postharvest application of xanthan coatings can be effective strategies for maintaining Orlando tangelo quality during cold storage.
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 ...
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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.
Shima Nasiri; Saman Abdanan; Mokhtar Heidari
Abstract
Introduction: Texture represents one of the four principal factors defining food/fruit quality, together with appearance, flavour and nutritional properties (Bourne, 2002), and plays a key role in consumer acceptability and recognition of quince. Textural characteristics of quinces defined by “crispness”, ...
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Introduction: Texture represents one of the four principal factors defining food/fruit quality, together with appearance, flavour and nutritional properties (Bourne, 2002), and plays a key role in consumer acceptability and recognition of quince. Textural characteristics of quinces defined by “crispness”, “juiciness”, “hardness”,“firmness” and “mealiness” are often key drivers of consumer preference. Many non-destructive methods, including image analysis, spectroscopy, ultrasound and sound techniques, have been developed to diagnose internal and external defects in fruits and vegetables. Cheng and Haugh (1994) used a frequency of 250-kHz, rather than 1-MHz, to detect hollow heart. They were not able to transmit successfully the ultrasound wave through the whole tuber using 1-MHz transducers but found the 250-kHz transducers to be practical for a transmission path length of up to 89.7 mm. In a research an acoustic setup was developed to simultaneously detect the resonant frequencies from equator and from calyx shoulder of pear. The researchers proposed index based on these two frequencies was used for firmness evaluation of non-spherical pear; Compared with two types of single frequency-based indices, the firmness sensitivity of the dual-frequency index is mostly close to that of MT penetration test. The firmness index can classify pears with a high total accuracy (93.4%), making it suitable for nondestructive detection of firmness of differently shaped pears (Zhang et al., 2018). The goal of this study was to develop a nondestructive method based on acoustic impulse response of quince fruit using genetic programming and artificial neural network during storage. Materials and Methods: In the experiment 120 quince fruits (Cydonia oblonga) were harvested from a field near Isfahan 181 days after full flowering of the trees. For each cultivar, only samples of similar size and without visible external damage were chosen. The samples were packed in sterile nylon bags and stored at 4°C. Non-destructive test (acoustic response) as well as destructive test (chemical measurement and penetration test) were performed every 15 days for 4 months (Akbari Bisheh et al., 2014). Total soluble solids (TSS) were determined by a hand refractometer device (model: MT03 Japan) and expressed as °Brix. Ascorbic acid of the juice was measured by titration with copper sulfate and potassium iodide based on the Barakat et al. (1973) procedure. Titratable acidity was measured according to the AOAC method. To determine the total phenol content of juice, the Waterhouse method (2000) was used. Determination of the pH of the fruit extract using a pH meter (Portable Model P-755, Japan). Physical attributes of the samples including volume as well as major, minor, intermittent diameters and mass were calculated using the relations proposed by Stroshine and Hammand (1994). Penetration test was conducted by the material test machine (SANTAM, STM-20 model, Iran).In order to analyze the response sound signal of quince in time and frequency domain, a system equipped with a sample holder with foam rubber covered surface, an impact mechanism, a microphone and an electronic circuit was utilized. To record impact sound features a microphone was positioned next to the fruit and was hit at three speed level (0.3, 0.9 and 1.5 m/s). After recoding sound, five features (acoustic peak, maximum acoustic pressure, mean acoustic pressure and natural frequency) were extracted and used as inputs for models. In order to predict the stiffness, four methods of genetic programming, neural network and existing mathematical models (FI and SIQ-FT) were used. In order to carry out statistical analysis, analysis of variance (ANOVA) and Duncan's multiple range test at 5% probability level were performed according to the completely randomized design (CRD). Results and discussion: In this study, Duncan's multiple range comparison test was used to investigate the significant difference between destructive and non-destructive parameters at 5% probability level. According to the results, acoustic peak, maximum acoustic pressure, mean acoustic pressure and natural frequency were decreased by increasing storage time. Statistical analysis of the destructive tests also showed a decreasing trend at the 5% level. In several papers, two mathematical equations have been used to obtain the relationship between the mass resonance frequency and the sound of impact. In this study, genetic programming and neural network modeling were used to compare the results of these relationships. The regression coefficients between the actual and the predicted values for the resonance-mass relation and the effect of the sound from the collision were R2= 0.601 and R2= 0.754, respectively. Also, the regression values obtained from genetic programming and neural network modeling were R2= 0.9567 and R2 = 0.933, respectively. In a research, the overall R2 value amounts for stiffness prediction was reported to be 0.79 (Schotte et al., 1999). Abbaszadeh et al. (2013) evaluated watermelons texture using their vibration responses. They declared their proposed method could predict textural acceptability of watermelons with determination coefficients 0.99. According to the obtained values, the best methods for stiffness prediction were genetic programming and f neural network methods, respectively.
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’ ...
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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 ...
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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).
Nasser Sedaghat; Nafiseh Vahedi
Abstract
In this study, quality of white button mushrooms (Agaricus bisporus) treated by water and citric acid was evaluated during storage at 2 temperatures (room temperature and 4°C). The effect of modified atmosphere packaging (MAP, by 4±1% CO2, 6±1% O2 and the remaining N2) with or without ...
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In this study, quality of white button mushrooms (Agaricus bisporus) treated by water and citric acid was evaluated during storage at 2 temperatures (room temperature and 4°C). The effect of modified atmosphere packaging (MAP, by 4±1% CO2, 6±1% O2 and the remaining N2) with or without water absorbent (silicagel) was also evaluated. Samples were assessed for their organoleptic properties (texture, color and spoilage), colorimetery and respiration rate during 12 days of storage. Results showed that among all treatments, water treated samples packaged with MAP method contained silicagel sachet and also stored at refrigerator obtained the most organoleptis scores. This sample retained the optimum level of inter packaging gas composition and finally the best storage time was determined as 8 days.
Soudabeh Einafshar
Abstract
Sour cherry is one of the most important horticultural products in Iran that consumes as fresh and dried fruit. In this research the effect of osmotic pretreatment on Physicochemical, antioxiative and microbial characteristics of 4 cultivars of sour cherry: Early Jibilium, Butermo, Sigany and Local were ...
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Sour cherry is one of the most important horticultural products in Iran that consumes as fresh and dried fruit. In this research the effect of osmotic pretreatment on Physicochemical, antioxiative and microbial characteristics of 4 cultivars of sour cherry: Early Jibilium, Butermo, Sigany and Local were investigated. The samples were placed in different osmotic solution, dried and vacuum packed in Polyamide pouches The physicochemical tests (pH, Bx, titrable acidity, moisture content, color, anthocyanin and phenolc compounds and antioxidative activities) and microbial tests were carried out after 6 and 12 months. The results showed that sour cherry Butermo var. had the most Bx, pH, acidity. Local and Early Jibelium var. had the least Bx and ph. The amount of moisture of Early Jibelium and Local var. were the most and the least, respectively. The chroma of Local var. was the most and had the more red purity than other varieties. Butermo and Local var. with 28.8 and 23.35 mg Cyanidin 3 Glychoside had the most and the least anthocyanins respectively. The amount of total phenolic compounds in Butermo Var. was significantly more than other varieties. The reducing power of Early Jibelium var. was the more significantly than other varieties. Osmosis process had no effect on the moicrobial growth, anthocyanins and phenolic compounds and antioxidative activities. One year storage significantly increased moisture, color, microbial growth, phenolic compounds and radical scavenging power of dried cherries but had no effect on other factors. The microbial conditions of samples were on the standard limits.
Soudabeh Einafshar; Parvin Sharayei; Mozhgan Shormij; Razieh Niazmand
Abstract
Saffron is the most important Iranian non oil export. Improper conditions of saffron flower storage increases microbial contamination and decreases saffron quality. This study was done for prolonging the shelf life of saffron flower in modified atmosphere packaging and subsequent to producing a new method ...
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Saffron is the most important Iranian non oil export. Improper conditions of saffron flower storage increases microbial contamination and decreases saffron quality. This study was done for prolonging the shelf life of saffron flower in modified atmosphere packaging and subsequent to producing a new method for exporting the fresh saffron flower as cut flower. Saffron flowers were packed in a polymer (Polyamide- Polyethylene bags) and three gas combinations of CO2, O2, and N2 (30%,5%,65%; 50%,5%,45% and 70%,5%,25% respectively). Samples and Control (without packaging) were kept at 0˚c for 15 days. Every three days the concentrations of oxygen and carbon dioxide inside the packages, the yield of product, physical (weight loss, percent of the flowers welter, the length and diameter of fresh stigma) and chemical properties (percent of moisture and the amount of Crocin, Safranal and Picrocrocin of dried stigma) were measured. The existence of E.Coli and enumeration of yeasts and moulds also were done. The results showed that modified atmosphere packaging increased the shelf life of saffron flowers. The chemical and physical qualities of control were lost strongly during 9 days. There were no evident for E.Coli growth in the samples. Enumeration of yeasts and moulds showed that most treatments were seen the national standard of Iran (103cfu/gr).
Hamed Darabi; Ali Asghar Zomorodian
Abstract
Lemon is one of the most important citrus fruit and is consumed as fresh and dry. In this study the effect of
fruit moisture content on the size, sphericity, geometric mean diameters and kernel density were studied. The
bulk density and porosity were also evaluated in three different arrangements. ...
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Lemon is one of the most important citrus fruit and is consumed as fresh and dry. In this study the effect of
fruit moisture content on the size, sphericity, geometric mean diameters and kernel density were studied. The
bulk density and porosity were also evaluated in three different arrangements. Airflow resistance is a
fundamental parameter for designing an efficient drying and aeration systems for lemon fruit bed. Using a
laboratory test rig, two sets of experiments were carried out: thick and thin layers. In the thick layer experiments
4 bed depths, 11 air flow rates and 4 air temperatures were adopted as independent variables. In the thin layer the
effect of filling arrangements in three patterns: A, B and random, at 5 moisture contents and 11 flow rates on
pressure drop were envisaged. Results showed that all the physical parameters listed decreased by reducing
moisture content. Results indicated that resistance to airflow through a column of lemon fruit increased with
increasing bed depth and airflow rate. In the latter experiment pressure drop decreased with a decrease in
moisture content. Airflow rate was the most significant factor affecting the pressure drop of lemon fruit in the
both experiment. Also the filling arrangement B has a higher affect on pressure drop comparing with other
arrangements. Three applicable models (Shedd, Hukill & Ives, and Ergun) were used to evaluate the pressure
drop data. The Ergun model, with higher values for coefficient of determination and lower values for root mean
square error, is the best model for predicting pressure drop across lemon fruit bed for the conditions studied.
