Postharvest physiology
P. Karimi Tazeiji; S. Rastegar; H. Hasanzadeh Khankahdani
Abstract
Introduction
Date fruit (Phoenix dactylifera L.) is one of the oldest known fruit crops and is considered as an important component of the diet in many Middle Eastern and North African countries. The fruit of date is nutritious, which is incredibly rich in carbohydrates, minerals, dietary fibers and ...
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Introduction
Date fruit (Phoenix dactylifera L.) is one of the oldest known fruit crops and is considered as an important component of the diet in many Middle Eastern and North African countries. The fruit of date is nutritious, which is incredibly rich in carbohydrates, minerals, dietary fibers and amino acids. Dates are one of the most important tropical fruits that play an important role in the country's economy. Among the date palm cultivars in Hormozgan province, Piyarom is one of the most commercial cultivars.
Recent studies by scientists have shown that the use of chemical compounds, in addition to environmental hazards, will cause various diseases in consumers due to the residual transfer of toxins to their bodies. Therefore, the management orientation of food preservation methods has moved towards reducing and eliminating chemicals and determining suitable alternatives, so that a certain time frame was set for the removal of some of the most important tobacco toxins.
In recent years, attention has been paid to aloe vera gel as a coating layer for fruits and vegetables to maintain their storage quality, and because it has no smell or taste, eating it does not pose a problem for humans and it is even good for health. L-arginine is one of the 20 major amino acids of living cells, which is a semi-essential amino acid in the human body. L-arginine and D-arginine are natural forms of common isomers of this type of amino acid.
The aim of the present investigation was the assess the effect of L-Arginine and Aloe vera gel edible coating on maintaining the external properties and the quality of semi-dried date fruit cultivars including Piyarom during storage.
Material and Method
The experiment was conducted as a factorial arrangement in a completely randomized design. The first factor was including seven treatments consisting of control, L-Arginine (1, 2, and 8 mM) and Aloe vera gel (25, 50, and 75%) and the second factor included storing (sampling) time for 9 months. In every measurement, the different attributes were evaluated such as weight loss percent; TSS; total acid; total phenol; flavonoid; color indexes including L*, a*, and b*; and antioxidant capacity. The level of antioxidant activity was evaluated by antioxidant agents by the method described by based on the trapping of free radicals of 2, 2-diphenyl 1-picryl hydrazyl (DPPH). DPPH solution was well combined with the methanol extract by means of a vortex and was incubated in the dark for 30 min. Then the absorption rate was read at 517 nm using a spectrophotometer. The color was determined using a colorimeter (Minolta, CR-400, Japan) after different months of storage. All measurements were done in triplicates. L* (100=white, 0=black), a* (–green, +red) and b* (–blue, +yellow) values were obtained at 400-700 nm range. The assay of the total phenol content was performed by applying the Folin–Ciocalteu colorimetric procedure. The total soluble solid (TSS) content of the fruit juice obtained for each replicate was determined using a hand-held refractometer Atago (Atago Co. Japan) at 25 °C; the results are expressed as % (°Brix). Titratable acidity (TA) was measured by titrating diluted juice with 0.1 N NaOH to a phenolphthalein end-point (pH 8.1-8.3). The results are expressed as citric acid %.
Results and Discussion
Based on the results, the treatments of Aloe vera gel and L-Arginine had significant effect on the quantitative and qualitative traits of Piyarom date fruits during storage. Storing time had significant influence (p<0.01) on the all parameters so that by passing storage time, the parameters including L*, a*, b*, a weight loss percent significantly increased and the parameters such as phenol, flavonoid and antioxidant significantly decreased. In the Piyarom cultivar, the treatments had significant effects on a*, b*, weight loss percent, phenol, flavonoid, and antioxidant, but it had no significant influence on TSS and total acid, so that the highest a* and b* color indexes was observed in the use of L-Arginine 1 mM, the greatest phenol and flavonoid in the application of L-Arginine 2 mM, the lowest weight loss percent in the use of Aloe vera gel 25 and 75%, respectively.
Conclusion
According to the results, 1 mM L-arginine treatment and 75% Aloe vera gel had a more effective role in maintaining the storage quality of Piyarom dates. The use of these treatments requires more extensive research on soft and dry dates.
Growing vegetables
S. Khosravi; M. Haghighi; M. Menatkhesh
Abstract
Introduction
Agaricus bisporus is the important mushroom that is cultivated industrially and due to its medicinal properties, it has special nutritional importance in the food basket of the people of the world. It is predicted that with increasing population and changing consumption patterns, ...
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Introduction
Agaricus bisporus is the important mushroom that is cultivated industrially and due to its medicinal properties, it has special nutritional importance in the food basket of the people of the world. It is predicted that with increasing population and changing consumption patterns, food will be one of the most critical issues in the country soon and protein poverty will be one of the most critical leading crises. Mushroom can be the best choice for the supply of essential human protein because they produce protein-rich foods using agricultural waste. Mushrooms are also rich sources of essential amino acids, vitamins (B2, niacin and folate), and minerals. White button mushroom production accounts for about 35% of the total world production of edible mushroom. The production of edible mushroom (Agaricus bisporus) depends on planting, amount of spawn consumed, growing conditions, species and media of cultivated edible mushroom.
Material and methods
The present study aims to investigate the effect of vitamins B and C on growth, yield of button mushroom and its postharvest life. The study was performed in two separate experiments in the mushroom factory and storage. The experiment was performed in the mushroom factory located in Khomeini Shahr city of Isfahan province and experiments related to the laboratory section and the research laboratories of the Faculty of Agriculture, Isfahan University of Technology. In this study, a box culture system was used to grow mushrooms. For this purpose, in order to prepare the culture media and prevent the mixing of culture media containing different treatments, cardboard plastic was used to make the boxes. First, in order to eliminate the pathogens, tiram fungicide is used for 24 hours. Cartonoplasts were then placed at specific distances of 30 cm by 30 cm. To eliminate pathogens, the composts were steamed in an autoclave at 121 ° C at a pressure of 1.34 atmospheres for 15 minutes and boarded and treatments were applied. Treatments include 3 levels of vitamin C (0, 3 and 6 mg / kg) (C0, C1 and 2C), 3 levels of vitamin B (0, 0.5 and 1 mg / kg) (B0, B1 and B2) was performed by factorial experiment in a randomized complete block design with 4 replications (40). Vitamin B complex, including vitamins B1, B2, B6, B12 and B9 were prepared in a ratio of 1: 2: 2: 5: 4. The treatments were applied to the composts used in the bed after boarding and before applying topsoil. When the mushrooms reached the commercial harvest level, i.e., the cap was 2.5 to 8 cm, but the cap was not opened, the factors related to vegetative growth were measured as follows. The number of mushrooms during the harvest period was counted for all treatments and at the end of the period, the average number of mushrooms per unit area was calculated. Cap diameter and base of each fungus were measured with a caliper during the harvest period for all mushrooms. In order to estimate yield, the mushroom harvested daily were weighed from all replications of each treatment.
Result
The results showed that the nutritional supplements used in this study were effective in increasing vegetative growth and yield and the highest number of mushrooms and dry weight were related to vitamin treatment. The interaction effect of vitamin C and vitamin B on the quantitative and qualitative characteristics of edible mushrooms at harvest time showed that dry weight increased at C1 and C2 with increasing concentration of B2 and decreased at C0. Cap diameter increased at all concentrations of vitamin C with increasing concentration of B2 and C2 had the highest amount. Base diameter was highest in C1 with increasing all concentrations of B vitamins compared to other treatments and lowest in C2 with concentration of B0. Ion leakage in C2 increased with increasing concentration of B2 and decreased in C0 and C1. The number of mushroom in C1 and C2 decreased with the addition of vitamin B and the highest number in C2 increased with the concentration of B0. The weight of grade 2 at C0 and C1 decreased with increasing concentrations of B2 and B1, respectively. Total yield was increased at all concentrations of vitamin C using B1. The highest total yield was observed in C1 treatment with B2 application. Total performance in control and C2 treatment decreased with increasing B2. Harvest time hardness increased in all three vitamin C treatments by increasing the concentration of B1, but increasing the concentration of B2 compared to B1 decreased. The highest increase was observed in the control treatment of vitamin C and the highest decrease was observed in the treatment of C2. Harvest time whiteness increased in C0 and C2 with the addition of vitamin B and decreased in C1. In general, in the control treatment of vitamin C in the two concentrations of B1 and B2, the highest amount of whitening time was observed. The highest amount of ash was observed in C2 with B2 application. In the postharvest experiment, the highest hardness after 32 days of storage was related to vitamin B treatment and the highest postharvest hardness, postharvest whiteness, and whiteness after 32 days of storage were related to vitamin C treatment. Also, the results of comparing the mean of interactions showed that the total yield in all three vitamin B treatments increased with the application of 3 mg/kg. The results of the second experiment showed that the rate of water loss in C1 with the addition of B2 concentration was the highest and in the control treatment was the lowest. The hardness increased after 32 days of storage in the control treatment and C2 with the application of B1, but decreased in C1 and C2 with the use of B2. The highest amount of whiteness was observed in C1 after 32 days of storage by increasing the concentration of C1, which was not statistically significant with the control treatment. It seems that there is not much difference between different concentrations of vitamin C in vegetative and postharvest fungal traits, but better results have been obtained by increasing the concentration of vitamin B. The results indicate that the effect of supplements on the yield of edible mushrooms is different so that adding appropriate amounts of supplements to the culture medium significantly increases crop yield. The results of this study showed that vitamin C1 treatment resulted in the highest dry and total weight, cap diameter, base diameter, and number of mushrooms. Wetter and drier cap and base diameters, ion leakage and water loss, were the highest in vitamin B2 treatment.
M. Azizi; H. Ahmadi; hossein arouiee
Abstract
Introduction: Evening primrose (Oenothera biennis L.) is a relatively new oilseed crops with high value which its oil is the most important source of gamma linolenic acid. In this study, seed of Evening primrose was stored in different temperature and packaging materials to improve the content and quality ...
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Introduction: Evening primrose (Oenothera biennis L.) is a relatively new oilseed crops with high value which its oil is the most important source of gamma linolenic acid. In this study, seed of Evening primrose was stored in different temperature and packaging materials to improve the content and quality of its oil.
Materials and Methods: In order to study the effect of packaging, storage temperature and storage period on Evening primrose seed oil properties, a split-plot in time experiment was conducted on the basis of completely randomized design at 32 treatments and three replications. Treatments included four levels of storage period (3, 6, 9 and 12 months) as main plot, four levels of packaging (Paper with 0.15 mm, Aluminum with 0.12 mm, PolyVinylChloride (PVC) with 0.09 mm and Cellophane with 0.07 mm thickness) and two levels of temperature (4 °C and Ambient temperature (20 °C)) as sub plots. Seed packages of 100 grams stored in plant physiology laboratory of horticulture department of Ferdowsi university of Mashhad from May 2014 to May 2015. After each period of storage seed oil (extracted by soxhelet) acid and peroxide value were examined as oil quality index. The statistical analysis was performed using the JMP software version 8 and data means were compared using LSD test’s in 5% level of probability. Acid and peroxide value were measured according to standards of EEC REG 2568/91 and AOCS cd 8-53, respectively.
Results and Discussion: Based on the results, the simple effect of temperature, packaging material and storage time was significant on all the properties of evening primrose oil. Before storage, seed oil content was 16.45% (w/w) but after three months of storage the oil content increased to 19.75% w/w. From third month of storage until 9th a sharp decline was observed, and the oil content was 12.71 % w/w at the end of 9th months. Finally the seed oil content slightly increased until 12thmonth. Before storage, acid and peroxide value were reported 1.16 (mg KOH/g oil) and 2.4 (meq O2/Kg oil), respectively. During storage, acid value showed descending trend so that at the end of 6 and 12 months storage obtained 1.08 and 0.96 mg KOH/g oil, respectively. Oil peroxide value after third months reached to 3.14 (meq O2/Kg oil) and its maximum (9.82 meq O2/Kg oil) was detected at the end of storage period. Ambient temperature in terms of oil content and 4 °C in terms of oil quality were optimum condition for Oenothera seed storage. Seeds samples which packed in paper and cellophane material showed the most oil content (17.29% and 16.75%, respectively). Cellophane packaging in terms of acid (0.89 mgKOH/g oil) and peroxide value (5.05 meq O2/Kg oil) was diagnosed the best packaging material to preserve the quality of the oil during storage. Interaction between storage temperature and storage period on oil percentage was significant at 1%. The highest oil percentage (59/22%) was detected after three months of storage at ambient temperature. Interaction between packaging and storage temperature on acid value of evening primrose seed oil was significant at 1% as aluminum packaging at ambient temperature and paper packaging in both temperatures had the highest acid value (1.15 and 1.11mg KOH/g oil, respectively). The lowest acid value (0.82 mg KOH/g oil) was detected in cellophane packaged seeds at 4°C temperature. Interaction between packaging material and storage period on acid value of evening primrose seed oil was significant at 1%. The highest acid value (1.24 mg KOH/g oil) obtained after six months in paper packaged seeds and seeds samples which packed in cellophane material had the lowest acid value (0.72 mg KOH/g oil) after nine months of storage. Interaction between storage temperature and storage period on acid value of evening primrose oil was significant at 1%. The highest acid value (1.11mgKOH/g oil) was detected after 12 months of storage at ambient temperature. At the end of 12th months at 4 °C temperature, the lowest acid value (0.81mg KOH/g oil) was reported. Interaction between packaging material, storage temperature and storage period on acid value of evening primrose seed oil was significant at 1% as paper packaged seeds after six months of storage at 4°C temperature and cellophane packaged seeds after 12 months of storage at ambient temperature showed the highest acid value (1.34 mg KOH/g oil). The end of 9th months in cellophane packaged seeds at both temperature, the lowest acid value (0.72 mg KOH/g oil) obtained. Interaction between packaging material and storage period on peroxide value of evening primrose oil was significant at 1% as paper packaged seeds after 12 months of storage had the highest peroxide value (11meq O2/Kg oil). Seeds samples which packed in PVC and cellophane material after three months showed the lowest peroxide value (2.15 and 1.85 meq O2/Kg oil, respectively). Interaction between storage temperature and storage period on peroxide value of evening primrose oil was significant at 1%. The highest peroxide value (10.01meq O2/Kg oil) was detected after 12 months of storage at ambient temperature. After three months of storage at 4°C temperature the lowest peroxide value (2.65 meq O2/Kg oil) obtained. Interaction between packaging material, storage temperature and storage period on peroxide value of evening primrose seed oil was significant at 1% as paper packaged seeds after 12 months of storage at 4°C temperature had the highest peroxide value (12 meq O2/Kg oil). The lowest peroxide value (1.60 meq O2/Kg oil) was detected in cellophane packaged seeds after three months of storage at 4 °C temperature.
Conclusion: Overall, evening primrose seed storage in paper and cellophane packaging during three months at ambient temperature to improve the content of oil was desirable. Seed storage in paper packaging at ambient temperature after12 months, reduced oil quality. Seeds samples which packed in PVC and cellophane material at 4°C temperature preserved the quality of evening primrose oil.
Javad Fattahi Moghadam; Seyedeh Elham SeyedGhasemi; Kazem Najafi
Abstract
Introduction: According to a breeding program that was carried out in Citrus and Subtropical Fruits Research Center, Noushin (C. reticulata cv Clementine × C. sinensis cv. Salustiana) and Shahin (C. reticulata cv Clementine × C. sinensis cv. Hamlin) mandarins were released by using crossing method ...
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Introduction: According to a breeding program that was carried out in Citrus and Subtropical Fruits Research Center, Noushin (C. reticulata cv Clementine × C. sinensis cv. Salustiana) and Shahin (C. reticulata cv Clementine × C. sinensis cv. Hamlin) mandarins were released by using crossing method in 20-year program. In general, mandarins do not have the ability of being kept in common or cold storage for long time compared to oranges. The main problem is the change of fruit taste during storage, therefore, it is an attracted subject for researchers. Furthermore, storage temperature plays an important role in the quality of the taste of mandarins. The new released mandarins, which hve not been yet studied completely for their storability, need to be evaluated. Therefore, the aim of this study was to investigate fruit physico-chemical and sensory characteristics of Noushin and Shahin varieties in common and cold storages for two years.
Materials and Methods: In this study, fruits of Noshin and Shahin mandarins were harvested at seasonal harvesting time and then placed in could storage (5 oC and 85% RH) and common storage (7-10 oC and 60-70 %RH) based on completely randomized design with three replications for 60 days every year. Fruits on days 0 (at harvesting time), 20, 40 and 60 of storage were sampled. Various physico-chemical and sensory characteristics were evaluated including iuice percentage, weight loss, peel color indices (L*, a*, b*, hue angle, chroma and CCI), total soluble solid (TSS), titratable acidity (TA), technological index (TI), skin disorder index (SDI), pH, electrical conductivity (EC), total phenolic, ascorbic acid, antioxidant capacity and sensory parameters during experiment. Statistical analysis of the data was performed using statistical software MSTAT-C. Analysis of variance combined in a randomized complete design (two years) with three replications for each variety.
Results and Discussion: The results showed that the amount of fruit weight loss and juice percentage did not show significant changes during storage. The ranges of weight loss in Noushin and Shahin varieties were 7-8% and 3.45-5.1%, respectively. Generally, peeling in Shahin was harder than Noushin but it gradually decreased until the end of storage. With the exception of citrus color index (CCI) in Noushin that was high at the beginning of storage, other color indices had no significant differences according to the type of variety and storage. Totally, TSS: TA ratio increased during storage depending on the type of storage, so that the ratio was higher (Noushin with 39.64 and Shahin with 13.34) in common storage than cold storage (Noushin with 31.04 and Shahin with 13.62) at the end of storage. Amount of electrical conductivity (EC) and technological index (TI) increased significantly in both varieties and storages. Shahin variety with 3.74 and 26.19% was so sensitive to rind disorder index and rind disorder percentage, respectively. Phenolic compounds in both varieties declined during both cold and common storages. The amount of reduction depends on the type of mandarin, with Shahin showing higher decline than Noushin variety. Besides, the content of ascorbic acid and antioxidant capacity in both peel and pulp showed a decreasing pattern with the passing of harvesting time during storage. According to sensory analysis, Noushin fruit can be stored in common storage for 20 days and in cold storage for 40 days. Moreover, results revealed that Shahin fruits did not have storability more than 40 days in common and cold storages.
Conclusion: Generally, Noushin variety was sensitive to low moisture of the storage and fruits lost extra moisture during storage. Since Noshin was an early ripening variety, TSS: TA ratio increased rapidly at the end of storage. Although Noushin had the lowest ascorbic acid content but its fruit antioxidant capacity was higher than shahin at the end of storage. On contrast, Shahin was a mid-ripening variety with higher ascorbic acid content. On the other hand, shahin peel was so sensitive to skin disorder index (SDI), therefor it should not be maintained in low moisture and temperature storage. Based on sensory analysis and physicochemical measurements, Noushin can be stored for 20 days and shahin for 40 days in common and cold storage. Finally, we found that Noushin and Shahin cannot be maintained in storage longer than other mandarins.
marjan Hosseini; seyed morteza zahedi; Mahdieh Karimi; Asghar Ebrahimzadeh
Abstract
Introduction: Mango (Mangifera indica) is a tropical fruit native to India whose global production in 2014 reached nearly 45 million tones. Mango is a commercially important fruit and improvement in its storage is of special importance. Mango is a Climacteric fruit whose ripening is done by exogenous ...
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Introduction: Mango (Mangifera indica) is a tropical fruit native to India whose global production in 2014 reached nearly 45 million tones. Mango is a commercially important fruit and improvement in its storage is of special importance. Mango is a Climacteric fruit whose ripening is done by exogenous or endogenous ethylene. In plants, Polyamines such as spermine, spermidine, and putrescine contradict ethylene because of a common precursor (s-adenosyl methionine (SAM). During ripening, different qualitative and nutritional changes occur in the fruit, e. g. changes in color, tissue softening, accumulation of sugars and organic acids, and great changes in taste, flavor, aroma and plant biochemical materials. Fruit ripening is a complicated process, complementary to fruit development, and a start to its senescence. In general, senescence of a fruit is related to loss of membrane lipids, destabilization of membrane matrix, and lipid peroxidation. Recently, naturally active biological products are applied in a large amount for increasing the storage life and quality of the fruits and delaying their senescence.This study was carried out to investigate the effect of different concentrations of spermidine on the quality and vase life of a local mango variety of Minab.
Materials and Methods: Healthy fruits, uniform in size, shape, color, and degree of maturity were selected from a mango orchard in Minab and their original physical and chemical characteristics on the first day were measured after washing with water and drying. Statistical analysis of data was done by a general linear model (GLM) with SAS (version 9.1) and mean comparisons were performed using Duncan's multiple range test. Treatment solution in the rate of 0, 0.5, 1, and 2 mM spermidine (SIGMA) was made and its pH was set to 5 using NaOH. One liter of distilled water was used in the control treatment. The treated samples were immersed in solutions of different concentrations of spermidine just once for 30 minutes. During 24-days of shelf life, storage temperature was 15 °C and the relative humidity was 85 to 90 percent. Measurements were on the zero, 8th, 16th, and 24th days. Characteristics such as weight, firmness, flavor index, phenol, ascorbic acid, qualitative characteristics (PH, TA and TSS), and sensory evaluation were measured.
Results and Discussion: The results showed that physical and biochemical qualities in the control fruit were lower compared to the other treatments. The Polyamine treatment with spermidine, especially at the concentration of 2 mM, significantly maintained weight loss and reduction of vitamin C during storage of fruits. Spermidine treatments increased ascorbic acid and other organic acids in fruit juice and reduced pH. Increased acidity in spermidine treatments of these substances play an active role in coping with storage stress. Moreover, with reduction of tissue respiration, the consumption of organic acids decreased during storage. The results showed that increasing the concentration of spermidine leads to the least decrease in the phenol flesh. Firmness gradually decreased during storage and at the end of shelf life, there was significant difference between the treatments. It was found that treatments with 1 and 2 mM spermidine were the best. Furthermore, the effect of spermidine on the total soluble solid solutions in the flesh of mango fruit was not significant during storage. But skin color, taste, flavor, and aroma index were more favorable. Treatments that delay production of structural lipids led to the production of aromatic volatile substances, which produced a favorable aroma in fruits. It seems that increasing spermidine concentration plays an important role in mango fruit fragrance at the end of shelf-life. The 2 mM spermidine treatment led to the highest total content of phenol and showed the lowest pH in fruit juice.
Conclusions: Spermidine, that is naturally present in animals and plants in particular, belongs to the amine groups. The results indicated that spermidine maintains firmness and extends shelf life of mango fruits and has a significant and beneficial impact on the quality characteristics including weight, color, taste, aroma, and vitamin C during storage. It seems that spermidine of 2 mM concentration has tangible impact on mango fruits and it is recommended in mango store rooms. There is a competition in production of Ethylene and polyamides of spermine, spermidine, and putrescine in plants, due to their common precursor namely S-adenosyl methionine, yet they act oppositely in ripening and senescence processes. Application of polyamides had extraordinary effects on the quality of some fruits during storage.
bahareh ghorbani; Z. Pakkish
Abstract
Introduction: Chilling injury (CI) is the primary postharvest problem of orange (Citrus sinensis L.) and many other horticultural crops during storage. Washington Navel orange fruits are susceptible to CI during storage below 5°C, and the main CI symptoms are surface pitting, browning, discoloration ...
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Introduction: Chilling injury (CI) is the primary postharvest problem of orange (Citrus sinensis L.) and many other horticultural crops during storage. Washington Navel orange fruits are susceptible to CI during storage below 5°C, and the main CI symptoms are surface pitting, browning, discoloration and decay. Several promising methods have been developed to alleviate CI symptoms of orange fruit. These include postharvest physical treatments with UV-C, modified atmosphere packaging, temperature conditioning, and chemical treatments with plant growth regulators. Oxidative stress from excessive reactive oxygen species (ROS) has been associated with appearance of chilling damage in fruits. The oxidation of ROS is due to their reaction with numerous cell components coursing a cascade of oxidative reactions and consequent inactivation of enzymes, lipid peroxidation, protein degradation, and DNA damage. Aerobic organisms have evolved well-developed defense systems to establish a fine-tuned balance between ROS production and removal plants are protected against ROS effects by a complex antioxidant system. This involved both lipid soluble antioxidant (α- tocopherol and carotenoids) and water soluble reductants (glutathion and ascorbate) and enzymes, such as catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD) and peroxidase (POD). Previous studies have shown that there is a positive relationship between the antioxidant enzymes activity and the chilling tolerance in harvested fruits. Nitric oxide (NO) is an important signaling molecule involved in many plant physiological processes. It has also been indicated that NO protects plant cells against oxidative stress by reducing ROS accumulation. When exogenously applied, NO has been shown to result in an improved chilling tolerance and reduced incidence of chilling injury in several fruits. The objectives of this study were to evaluate the effects of NO on chilling injury, lipid peroxidation content, peroxide hydrogen content, and the induction of antioxidant enzymes in Washington Navel orange (Citrus sinensis L.) fruit during storage at 5±1°C.
Materials and Methods: Washington Navel orange (Citrus sinensis L.) fruits were harvested at commercial maturity from a commercial orchard in Kerman, Iran, and transported to the laboratory on the same day. Orange fruits were treated with 0.25 and 0.5 mM nitric oxide for 5 min and then stored at 5±1°C and relative humidity of 85-90 % for 5 months. No nitric oxide use was considered as control. The experiment was arranged in completely randomized design (CRD) with three replicates. Characteristics such as chilling injury, total soluble solids, titratable acidity, pH, ascorbic acid, and activity of antioxidant enzymes (peroxidase and catalase) were evaluated in the present experiment.
Results and Discussion: The results showed that use of nitric oxide in fruits reduced significantly chilling injury, ion leakage, lipid peroxidation and hydrogen peroxide compared to control, though it increased activity of antioxidant enzymes. According to these results, unlike organic acids which decreased in treated and non-treated fruits, total soluble solids, ascorbic acid and pH of the fruits increased during storage, however, nitric oxide treatment reduced the rate of changes, be either reducing or increasing, in the mentioned parameters compared to control. So, fruits treated with 0.5 mMol nitric oxide showed the highest effect on the reduction of chilling injury.
In the present study, the results indicated that NO significantly reduced CI of orange fruits during storage at 5±1 °C. NO has been applied to reduce the development of chilling injury symptoms in a number of horticultural crops. Thus NO has the potential of application in postharvest treatment by alleviating chilling injury and maintaining quality, and the aim of this study was to determine how NO alleviates the anti-oxidative systems, probably one of the mechanisms of improved chilling tolerance, of orange fruit during chilling stress. This indicates that the chilling tolerance of orange fruit was also enhanced by postharvest treatment with NO. Lipid peroxidation and protective enzyme systems are often evaluated in studies of plant mechanisms under various stresses. Low temperature disrupts the balance of active oxygen species metabolism, leading to their accumulation and destruction of scavenging enzymes such as catalase and peroxidase. In the present study, exogenous per-treatment with nitric oxide at 0.25 and 0.5 mM significantly decreased the lipid peroxidation content and electrolyte leakage of cold stored orange fruit compared to untreated fruits. The level of H2O2 was maintained by NO treatment, which led to an increase in chilling tolerance. It has been reported that the improvement of chilling tolerance in harvested horticultural crops is related to the enhancement in activates of antioxidant enzyme. Researchers found that chilling-tolerant mandarins have a higher antioxidant enzyme activity than the chilling-sensitive ones. A number of postharvest treatments that induce chilling tolerance and alleviate chilling injury also enhanced antioxidant enzyme activity. However, to the best of our knowledge, this is the first paper reporting the beneficial effects of NO on CI of postharvest orange fruits. In this study, there was a continuous increase in peel and pulp lipid peroxidation content in all fruits, but the application of NO significantly delayed the increase of lipid peroxidation. Moreover, the change in membrane permeability (revealed by H2O2 content) showed trends similar to lipid peroxidation content; in other words, peel and pulp H2O2 content increased with storage duration, but NO markedly delayed the increase. NO has been considered to be involved in a network of interacting signal transduction pathways, which regulate defense responses to abiotic stress. The detoxification of ROS is dependent on antioxidant enzymes such as CAT and POD. The increase in these enzymes’ activity contributes to the adaptation of plants to cold stress and ameliorates oxidative damage such as lipid peroxidation (lipid peroxidation increase as indicator) and H2O2 content.
Conclusion: In conclusion, application of NO reduced CI of oranges stored at 5±1°C and maintained oranges quality as well. The chilling injury, lipid peroxidation, and peroxide hydrogen were significantly reduced by NO treatment especially at 0.5 mM. Induced cold resistance by NO treatment may be due to the stimulation of antioxidant enzymes, and protection against membrane oxidative damage, decreased lipid peroxidation and H2O2 content in orange fruits. These results may have implications for the use of NO in managing postharvest CI of other subtropical fruits stored at low temperatures.
Seied Mehdi Miri; Meysam Salari; Ahmad Ahmadpour
Abstract
Introduction. Citrus is one of the most commercially important horticultural crops grown in tropical and sub-tropical regions of the world. They are classified as non-climacteric fruits. Harvesting date and storage can influence citrus fruit quality and shelf life. In Iran, some members of citrus family ...
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Introduction. Citrus is one of the most commercially important horticultural crops grown in tropical and sub-tropical regions of the world. They are classified as non-climacteric fruits. Harvesting date and storage can influence citrus fruit quality and shelf life. In Iran, some members of citrus family including sweet orange and mandarin are produced as an export crop, so research on fruit quality and storage life is needed. There is no available scientific literature regarding the effect of harvesting date and storage duration on retaining the postharvest physicochemical properties of Kinnow mandarin under cold storage. The main objective of the present study was to evaluate the effect of harvesting date and storing time on shelf life and quality of Kinnow mandarin fruits under Jiroft weather conditions.
Materials and Methods. Investigations were carried out on mandarin (Citrus reticulata) cv. Kinnow grafted on sour orange rootstock in an orchard located in Jiroft and Kahnooj Agricultural Research Center, Jiroft, Iran. Fruits were harvested on 6th December, 21th December, 5th January, 20th January and 4th February. After cold storage for 30-90 days at 4-6 °C, the fruit was analyzed for quantitative and qualitative characteristics including weight of fruit, peel, meat, pulp and juice, fruit weight loss, pH, total soluble solids (TSS), titratable acidity (TA) and TSS/TA. Experiment was arranged in a split plot based on randomized complete block design (RCBD). Data analysis and similarity coefficient (Pearson's method) were performed using SPSS.16 software, and means comparison was performed by using Duncan's multiple range test at 1 and 5% probability levels.
Results and Discussion. The results showed that the interaction effect of harvesting date and storage period on the weight of the fruit, meat, pulp and juice and TSS, TA and TSS/TA was significant at 1% probability level. Weight of harvested fruits from 6th December to 5th January was constant, but fruits harvested on 20th January and 4th February were heavier as much as 12.5 and 14.3 percent, respectively, compared to 6th December. Fruit weight loss increased along with the increase in storage time duration, so that mean fruits weight loss percentages were 3.5 and 16.5 at 30 and 90 days of storage, respectively, due to continued transpiration of the fruits after harvesting. As a result of transpiration, water enters into the atmosphere through the pores existing on fruit surface. The greatest fruit weight (121.8 g) was recorded for combination of harvesting on 20th January and 30-day storage. Fruits harvested on 20th January and 30-day storage had higher meat and pulp weight (89.6 and 52.3 g, respectively) and a significant correlation coefficient was detected between them. Changes of fruit juice pH at different stages of fruit ripening and storage times did not follow a fixed pattern, though pH slightly increased in some cases during storage, which can be due to oxidation of citric acid during storage. The maximum TSS was recorded for harvesting on 5th January and 90-day storage (11.7 °Brix) as well as 4th February and 60- and 90-day storages (11.8 °Brix), while the minimum TSS was observed on 6th December and 30-day storage (8.7 °Brix). The results exhibited that TSS content of fruit juice increased when storage period increased, which was possibly attributed to the hydrolysis of starch and increase in sucrose content. However, increase in TSS during storage is not always directly related to changes in the simple sugar content of fruit. During storage and maturation of the fruits on the tree, TA reduced due to the use of citric acid in respiration. Taste index (TSS/TA) in fruits harvested at full maturity was greater than that in fruits harvested in the fall. Besides, TSS/TA increased during storage, so that the highest and lowest average TSS/TA ratios were related to harvesting on 4th February and 30-day storage as well as 6th December and 30-day storage, respectively. According to the results, fruits did not reach full maturity until 5th January under Jiroft weather conditions.
Conclusion. Postharvest quality and shelf life of Kinnow mandarin fruits were affected by harvesting date and storage duration. Delay in harvest resulted in an increase in fruit weight, TSS and TSS/TA. TSS and TSS/TA were higher when fruits harvested on 4th February. Fruit weight loss increased when the storage period increased.. Overall, 4th February is the best date to harvest Kinnow mandarin fruit in Jiroft.
manizhe khanian; davood ghanbarian
Abstract
Introduction: Because of harvesting of widespread volume of pomegranate production in a short time from late summer to early autumn and due to the lack of appropriate conditions of storage, a large part of which is lost prior to the market presentation or its cost is reduced due to the widespread presentation. ...
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Introduction: Because of harvesting of widespread volume of pomegranate production in a short time from late summer to early autumn and due to the lack of appropriate conditions of storage, a large part of which is lost prior to the market presentation or its cost is reduced due to the widespread presentation. Some studies investigated different methods for long-term storage of pomegranate, including use of alternative heating, low temperature, controlled atmosphere and growth plant regulators. Pomegranates are usually kept at temperatures below 5 °C only for 2 months, and then, frostbite to form of surface stains, skin browning; discolouration and browning of Arils and separator membrane are appeared. However, sensitivity to frostbite is a major problem for pomegranate storage, but generally the most important limiting factor for pomegranate storage is the growth and development of fungal contaminations, especially on the part of the throat. This problem is usually intensified at temperatures above 5 °C to prevent frostbite pomegranate. Therefore, for long-term storage of pomegranate, dual problem exists. It means that to reduce frost, we have to use higher temperatures or plastic covers, and on the other hand all these conditions can intensify the fungal decay in pomegranate. Recently, the interest of consumers has increased to food products with better quality, fresher and easier access. In this regard, packaging materials and packaging methods with the use of modern and appropriate techniques play vital role in reducing food wastes and production which is caused to healthier products. Considering the importance of extended life storage along with the preservation of favorite pomegranate quality, so the objective of this study was to investigate the effects of four types of coverage on the quality of pomegranate.
Materials and Methods: Maikhosh pomegranate cultivar was used for this study. Samples were taken directly from the Najaf Abad city orchards at the same conditions. Fruit weight was measured at the beginning of the experiments using a digital balance and then pomegranate samples were coated and stored at 4 °C for 105 days and every 35 days, the physical and chemical properties of pomegranates were measured. Initial weight of the samples stored were measured every 35 days and the percent of weight loss was calculated using Equation (initial weight-secondary weight / initial weight) × 100. In addition, the outer skin browning of fruits as one of the frostbite indices was examined. The sphericity coefficient i.e., the degree of similarity of each sample to sphere was expressed as Q = (abc) ^(1/3) / a ×100 The total surface area of the samples was determined using relationship S= π〖((abc)〗^(1/3))^2. Area brown skin of the samples was calculated by application of Imag j software. The percent of browning index was calculated by relationship (brown area of sample)/( total surface sample area), and each percentage of browning fruit were given from zero to five and frostbite percent was measured using relationship, percent of frostbite = (marks total ×100)/(number of biopsied sample×5). Firmness was measured using a manually penetrometer (ABI-ASA, Netherlands) equipped with a probe with 8 mm diameter. The pH values were measured using a pH-meter (MTT65, Iran) for the measurement of pH, 1 ml of pomegranate juice was mixed with 9 ml of distilled water using two device buffer solution with pH = 4 and pH =7. The TA was determined by mixing 1 ml of pomegranate juice with 9 ml of distilled water in the presence of phenolphthalein and titrating with 0.1 mol L-1 NaOH (PH 8.1) and using a calculated relationship TA=(M×0/0064×100)/W. TSS contents were recorded in a soluble refractometer (ATAGO, Japan) with values being expressed as 0Brix. The color content and intensity were measured using strewing pomegranate juice into centrifuge tubes with length of 20 ml and was centrifuged at 4000 rpm for 15 minutes. Then, the absorbance within 420-520 nm was measured in a spectrophotometer, and finally the color content and intensity was calculated by A520 + A420 and A420 /A520, respectively. Statistical analysis was performed using SAS software. Differences among means were tested for significance by ANOVA procedures and LSD test.
Results and Discussion: The analysis results showed that the coating treatments had a significant effect on all properties while storage period had a significant effect only on pH, percent of weight loss, frosting percent, acidity and soluble solids content. The samples coated by chitosan solvent 1% showed greatly weight loss in comparison with other coating treatments. Because the high concentration of chitosan causes preservation moisture between chitosan and skin of fruit that this could increase the activity of the aerobic pathogens, decay and higher weight loss. Firmness of fruits coated by liquid paraffin greatly reduced during storage period in comparison with other coating treatments. The soluble solids content of fruits covered by chitosan solvent 1% showed greatly an increase during storage period in comparison with other coating treatments. Coating treatments had a significant effect on the color content and intensity at level of 0.05 and 0.01, respectively. The coating aloevera gel treatment showed the lowest color intensity and content which suggests maintaining anthocyanin pigments and reducing brown pigments in samples. Among all coating treatments, the pomegranate peel extract indeed of conservation of apparent quality of fruits and seeds, showed the lower frosting percent approving the favorable effect of this treatment on the preservation of fruit in cold storage.
Conclusions: The results showed that among applied coatings, pomegranate peel extract is the best option due to the conservation of apparent quality of fruits and seeds as well as the lower frosting percent. The coating treatments aloevera gel and pomegranate peel extract showed the lowest color content and intensity and they are more appropriate options due to conservation of transparency and color red, respectively. Therefore, the treatment coating pomegranate peel extract and aloevera gel were chosen as the best options in pomegranate storage.
M. Hamedani; H. Moradi; A. Ghanbari
Abstract
The different factors such as harvest time, product handling, temperature and storage duration can be influenced on the different properties of citrus fruits and has considerable economic consequences. Therefore a factorial experiment based on completely randomized design with 3 replications was performed ...
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The different factors such as harvest time, product handling, temperature and storage duration can be influenced on the different properties of citrus fruits and has considerable economic consequences. Therefore a factorial experiment based on completely randomized design with 3 replications was performed to evaluate the effects of harvest times (start of color change, 50% of color change and full color change of fruits), storage period (0, 25, 50 and 75 days) at 7ºC on total soluble solids, titrable acidity, ascorbic acid, total phenol content, flavonoid, antioxidant capacity, anthocyanin and activity of L-phenylalanin ammonia-lyase. The results showed that the harvest times and storage period had significant effect on the measured properties. So that the after 75 days of storage, peak phenylalanin ammonia-lyase activity and total flavonoid observed concomitantly with the accumulation of anthocyanin in ripe blood orange fruit but decreased antioxidant capacity and total phenol after 25 days of storage. Also, the highest vitamin C content and total soluble solids were measured in full ripening of fruits before storing and decreased after 75 days storage. So, according to changes in all of measured characteristics, the apropriate time of harvesting of Moro blood orange was the stage of commercial maturity of fruits.
E. Barzanooni; Mohammad Hosein Aghkhani; A. Maskooki; M.H. Abbaspour Fard
Abstract
Postharvest losses are a limiting factor on storage life of many vegetables and fruits including citrus. Therefore a study was conducted to evaluate the effects of thermal treatments and herbal thyme oil spray on Sanguinello blood oranges in Golestan province in the northern part of Iran. The tests have ...
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Postharvest losses are a limiting factor on storage life of many vegetables and fruits including citrus. Therefore a study was conducted to evaluate the effects of thermal treatments and herbal thyme oil spray on Sanguinello blood oranges in Golestan province in the northern part of Iran. The tests have been performed one day after harvesting, under four different treatments: hot water at 55˚C for 3 minutes, flushing of steam at 100˚C for 30 seconds, and spraying of fruits with two-percent thyme using surfactant. The fruits of each treatment were then kept in some boxes and placed in a cold storage at 8˚C and relative humidity of 85±5 percent, for two months. Results showed that the treatments had no significant effect on the quality parameters of fruits such as acidity, total soluble solid, maturity index and sensory evaluation. However, among all treatments, the steaming treatment had the greatest impact in preventing weight loss during storage.
M. Mackvandi; S. Shahpory; A.A. Ramin
Abstract
The effects of postharvest application of 1-methylcyclopropene (1-MCP) and calcium chloride dip or their combination on storage quality of mature-green olives (Olea Europaea cv. mission) were examined. The experiment was conducted using a completely randomized design with three replications, in a factorial ...
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The effects of postharvest application of 1-methylcyclopropene (1-MCP) and calcium chloride dip or their combination on storage quality of mature-green olives (Olea Europaea cv. mission) were examined. The experiment was conducted using a completely randomized design with three replications, in a factorial array. The effects of treatments were evaluated by recording: chlorophyll (SPAD), quantum efficiency of photosystem II (Fv/Fm), skin color and flesh firmness. Results showed that, non-treated fruits (control) softened within 14 days (2 weeks) after harvest, While, postharvest treatment with 1-MCP significantly reduced the fruit softening and color changes. Furthermore, 1-MCP had only minor effect on quantum efficiency of photosystem II (Fv/Fm). The CaCl2 treatments showed a significant reduction in fruit softening, but had no effects on chlorophyll (SPAD), quantum efficiency of photosystem II (Fv/Fm) and fruit color. It was concluded that the combination of 1-MCP and CaCl2 had synergistic effect on preventing of fruit softening. Hence, olives remained firmness for 35 days at 20oC with minimum softening.
H. Shirzad
Abstract
The use of natural compounds to control plant pathogens lead to reduction in using fungicides. Chitosan with duble effects, control pathogenic microorganisms and activate inducing defence responses, has been shown to be a reliable nontoxic material in the plant-pathogen interaction. The aim of this research ...
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The use of natural compounds to control plant pathogens lead to reduction in using fungicides. Chitosan with duble effects, control pathogenic microorganisms and activate inducing defence responses, has been shown to be a reliable nontoxic material in the plant-pathogen interaction. The aim of this research was to consider the effects of chitosan and calcium chloride on decay and quality attributes of sweet cherry cv. Siah mashhad. This experiment was conducted factorially in the figure of completely randomized design with five replications. Treatments were included of chitosan (0, %0.5 and %1) and Calcium Chloride (0, %1 and %2) and time (20 and 40 days). Measuring factors was included total soluble solids (TSS), titrable acidity (TA), partability index (PI), pH, weight loss, fruit decay. The results showed that application of chitosan %0.5 alone lead to stabilize soluble solids, organic acid, pH and fruit weight, also partability index and fruit rot was decreased. In short time storage (20 days) CaCl2 stabilize organic acids and fruit weight and caused partability index, pH, fruit decay to be decreased but fruit soluble solids increased. In total simple treatment of calcium chloride and chitosn showed better results compared to combination treatments on measured parameters.
Javad Fattahi Moghadam; M. Fazel Halajisani
Abstract
The harvest date more influenced on postharvest quality during storage. In present study, fruits were harvested at four date base on total soluble solids content (5.5, 6.5, 7.5, and 8.5%) and then stored at 0.5 ºC and 80-90% RH, for 18 weeks. The samples were taken in 6th, 12th and 18th interval weeks ...
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The harvest date more influenced on postharvest quality during storage. In present study, fruits were harvested at four date base on total soluble solids content (5.5, 6.5, 7.5, and 8.5%) and then stored at 0.5 ºC and 80-90% RH, for 18 weeks. The samples were taken in 6th, 12th and 18th interval weeks and evaluated some parameters including weightless, losses, firmness, TSS, TA, TSS/TA, ascorbic acid, pH, EC, Skin and pulp lightness and sensory analysis. Results showed that different harvesting time had not significant effect on wieghtloss and pH parameters during storage. Also, we observed that fruits which were harvested at brix of 5.5 had high firmness specialy during primery 6 weeks storage. The skin of fruits picked with 5.5 and 6.5 % brix was a little darker than other treatments. EC showed reverse relationship with storage period during storage. With TSS increasing, TA level decreased during storage. Although, ascorbic acid content was higher during 6 weeks of storage but it was lower in fruits which picked with 5.5 % brix than other times of harvest. Finally sensory analysis revealed that fruits which harvested at least 6.5 oBrix content, would have excellent quality after storage and handling.
