Postharvest physiology
M. Rahemi; M. H. Nazaran; S. Abolghasemi; S. Sedaghat; M. Zare
Abstract
Introduction
Low temperature storage is the most important method used to preserve harvested products. Keeping products at low temperatures, above the freezing point up to 10 degrees Celsius, can cause frost damage in fruits and vegetables, especially tropical and subtropical products. The use of heat ...
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Introduction
Low temperature storage is the most important method used to preserve harvested products. Keeping products at low temperatures, above the freezing point up to 10 degrees Celsius, can cause frost damage in fruits and vegetables, especially tropical and subtropical products. The use of heat treatments as safe, organic and alternative physical methods is increasing, these treatments are used to maintain the quality after harvesting and also to prevent frostbite of garden products. Also, one of the recommended methods to reduce fruit waste is to increase the calcium concentration of the fruit by using calcium solutions. Calcium is one of the most important mineral elements that is involved in determining the quality of the fruit and its shelf life. Studies conducted on the use of nano fertilizers in some species of fruit trees has shown their potential role in improving the yield of the product and the physical and chemical properties of the fruitThis study was conducted to investigate the effect of postharvest treatments of calcium chloride and nano chelated calcium fertilizers on chilling injury and physiological characteristics of local orange fruits stored at 2 ±0.5° C and 85% relative humidity for 60 to 120 days.
Materials and Methods
In this research, orange fruits of the local cultivar Citrus sinensis at the stage of commercial maturity based on the taste index (10TSS/TA⋍) were prepared from Darab city of Fars province and transferred to the Physiology Laboratory of Horticultural Sciences Department of Shiraz University. Then the fruits were disinfected with 2% sodium hypochlorite and washed with distilled water. Treatments included calcium chloride and nano chelated calcium fertilizers at different concentrations of zero, 3 and 6 dissolved in cold water (20°C) and hot water at 45 °C for 25 and 15 min, respectively. Sampling was done on days 60 and 120. To simulate shelf life conditions, before measuring the parameters, the fruits were kept at laboratory temperature for two days. In this research, the changes in fruit tissue firmness, freezing index, weight loss percentage, soluble solids, total acidity, ascorbic acid, ion leakage, potassium ion leakage, malondialdehyde, calcium content of fruit skin and flesh, fruit color, catalase enzymes and peroxidase were measured. Data analysis was done using SAS software version 4.9 and comparison of averages was done by LSD test at 5% probability level.
Results and Discussion
There was a significant difference between nano chelated calcium and calcium chloride in calcium enrichment in pulp and fruit skin Calcium chloride and nano chelated calcium treatments dissolved in hot water reduced weight loss, soluble solids content, acidity, ascorbic acid, ion leakage and malondialdehyde and the activity of the antioxidant enzymes catalase and peroxidase. Nano chelated calcium increased calcium content by 44% in fruit skin and up to 41% in fruit pulp compared to calcium chloride. Nano chelated calcium 3 and 6 % showed more stability in fruit weight (159 and 400%, respectively) compared to calcium chloride after two months of storage. After 60 and 120 days of storage, the content of ascorbic acid in fruits treated with 6 nano chelated calcium was 73% higher than calcium chloride. Nano chelated calcium 3 % compared to calcium chloride prevented 39.6 of potassium ion leakage during 60 days of storage. The amount of ascorbic acid in the 3% and 6% nano calcium treatment and the tissue hardness in the 3% nano calcium chelate treatment after two months of storage were estimated to be higher than the control and calcium chloride. Calcium nano chelate 6% improved the calcium content of fruit flesh and skin due to increased permeability. Warm water pretreatment with calcium compounds is an efficient and recommendable treatment for the preservation of orange fruits in cold storage conditions due to the improvement and reduction of the severity of the increase in indicators related to the occurrence of frost damage in the skin of fruits.
Conclusion
One of the primary concerns during storage is the loss of fruit weight. Calcium nano chelate, in comparison to the control and calcium chloride treatments, exhibited the least weight loss over the two months of storage. This is attributed to the critical role of calcium in influencing the shelf life of fruits. It was observed that immersing fruits in calcium compounds dissolved in hot water and utilizing 6% nano chelated calcium had a significant positive impact on enhancing and preserving the quality of orange fruits during cold storage.
Growing vegetables
S. A. Yaqoobi; S. H. Nemati; M. Azizi; M. Shoor
Abstract
Introduction Storage potential is an important characteristic for onion. Annually, a large quantity of worldwide onion production deteriorated during storage. The storage ability of onion is influenced by various endo- and exogenous factors including cultivar and storage conditions specially, temperature. ...
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Introduction Storage potential is an important characteristic for onion. Annually, a large quantity of worldwide onion production deteriorated during storage. The storage ability of onion is influenced by various endo- and exogenous factors including cultivar and storage conditions specially, temperature. Based on literature, there is considerable genetic variation for onion storability in onion germplasms from different origins. Rivera Martínez et al. (2005) evaluated the storability of 18 local and 4 commercial onion cultivars in Spain. Their results showed that there was significant variation for storability among different onion cultivars, and interstingly the local cultivars had more storability than commercial ones. Onion storage could also affected by environmental conditions such as temperature. Benkeblia et al. (2000) studied the effects of various temperatures on respiratory parameters of onion. Their finding showed onion respiration were raised by increasing temperature. Likewise, the positive effect of higher temperature on enhancing the growth of sprouts and elevating transpiration has been reported (Miedema, 1998; Yoo et al., 1997). Although, Afghanistan is considered to be one of the origins of onion (Brewster, 1994) there are no reports on estimating the storability of Afghan local cultivars under different temperature conditions. So this research has been conducted to study the effects of various temperatures on storability of native onion cultivars of Afghanistan.Materials and Methods In this research, the plant materials consisted of 10 onion cultivars consisting eight local varieties “Hanaaie Harat”, “Zard-e-Harat”, “Ghermrz-e-Harat”, “Mazar-e-Sharif”, “Kabul”, “Sar-e-Pul”, “Ghonduz” and “Balkhaab” originated from Afghanistan, an Iranian cultivar (“Ghermez-e-Azarshahr”), and a commercial cultivar “Sweet Grano”. The cultivars were stored at two different temperature regimes (5 ºC and ambient temperature), during six-time intervals of 20 days. The average temperature of ambient storage was 13 °C ranging from 8-18 °C. The experiment lasted from November 6th, 2011 to March 5th, 2012. This research was performed in a completely randomized design based on split factorial design, with three replications. For each replication, 50 healthy non-sprouted bulbs were packaged in plastic nets. Storage potential related characteristics such as sprouting percentage, weight loss percentage, sprout length, and sprout weight/bulb weight ratio in 20 days intervals were measured. All data were subjected to analysis of variance (ANOVA) using SAS statistical software. Mean comparisons were calculated at 5% probability level using LSD when the F-value was significant (Fisher’s protected LSD).Results and Discussion The results showed that there were significant differences among cultivars for storage characteristics (weight loss percentage, sprouting percentage, length of sprouts and sprout weight/bulb weight ratio). “Ghonduz” and “Ghermrz-e-Harat” local cultivars had the most and least storage ability, 50% of bulb sprouting after 105 and 35 days, respectively. Rivera Martínez et al. (2005) and Ramin (1999) also reported Spanish and Iranian local cultivars had more storability compared to commercial cultivars. In 5 °C, weight loss of onion bulbs followed a linear model during storage period. But, in ambient storage, it was higher at the beginning and the end of storage period, showing the adverse effects of high temperatures on bulbs weight loss during storage. The interaction between cultivar and time was also significant. It showed onion weight loss differs in various intervals. It could be attributed to the genetic variation and morphological difference such as number and thickness of dry scales of onion bulbs. In ambient storage condition, onion sprouting percentage showed a sharp increase in early storage intervals and became stable in the late intervals. Under 5 °C treatment, it raised as a linear model with very slow slope. It seems that weight loss and sprouting of onion bulbs in ambient storage is dependent on temperature and relative humidity of environment. This finding is in agreement with previous reports (Baninasab and Rahemi, 2006; Forudi, 2005). The sprout length and the ratio of sprout weight to bulb weight was lower in 5 ºC than ambient temperature. Abdalla and Mann (1963) and Yoo et al. (1997) also reported that smaller sprouts were observed in lower temperatures. Conclusion In this experiment, the effects of temperature on storability of some local cultivars of onion originated from Afghanistan were studied in different intervals. It was found that the storage potential of onion bulbs could be influenced by genetic factors and environment conditions such as temperature. Findings of this research showed that sprouting percentage, weight loss percentage and onion sprout growth were less under 5 °C treatment than ambient temperature. Therefore, it was concluded that storing onion bulbs in low temperature conditions can reduce the onion spoilage and improve their storage life. Additionally, cultivars showed highly significant variations for all characteristics related to storage ability. Our findings showed that some local cultivars are more storable than commercial cultivars. Among the cultivars, “Ghonduz” cultivar has more storage potent as compared to all studied cultivars. Our results confirmed that local cultivars can be a good source of desirable genes related to storability. Subsequently, they can exploited to broaden the genetic base of breeding matreials.
Postharvest physiology
V. Anisi; Y. Selahvarzi; M. Kamali; B. Abedi
Abstract
Introduction
Cucumber is a vegetable with a low capacity for storage; it usually loses quality 14 days from the beginning of storage. The benefits of cold storage are not the same for all the fruit or vegetables, some given vegetables are more suitable for cold storage than others. However, pre-cooling ...
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Introduction
Cucumber is a vegetable with a low capacity for storage; it usually loses quality 14 days from the beginning of storage. The benefits of cold storage are not the same for all the fruit or vegetables, some given vegetables are more suitable for cold storage than others. However, pre-cooling is always advisable, because the products takes profit from the benefits of low temperatures in cold storage rooms. Due to the short shelf life of cucumber and the high speed of reducing its quality, various methods are used to maintain the quality of cucumber, such as edible coatings. Propolis, also called “bee-glue,” is a natural resinous substance produced by honeybees from plant exudates, beeswax, and bee secretions in order to defend the hives. Propolis has an important role in prevention of food loss weight and waste, thus helping to ensure food safety and security. The concoction of aqueous propolis extracts has a lower cost as compared to hydroalcoholic extracts and it is believable that both, aqueous and hydro alcoholic extracts, present similar concentrations of phenolic compounds resulting in a product of appropriate functional characteristics. Herein, the biochemical composition and efficacy of propolis in maintaining the postharvest storability of food products were discussed to provide a comprehensive guide to farmers and food processing and storage sectors and to scientists.
Materials and Methods
In order to investigate the effect of two factors of hydro cooling and propolis as an edible coating on cucumber shelf life, this study was conducted in the spring and summer of 2019 in the laboratories of horticultural sciences, Faculty of Agriculture, Ferdowsi University of Mashhad. The factorial experiment was based on a completely randomized design. Experimental treatments included three levels of propolis alcoholic extract (0, 4 and 8%) and two temperature treatments (4 (hydro cooling temperature) and 25 ° C) in 4 replications.
Weight loss, tissue firmness, extract pH, total soluble solids, chlorophyll a, chlorophyll b, total chlorophyll, total phenol and antioxidant activity were measured. The experimental data were analyzed using Jump-8 statistical software and the means of treatments were compared by LSD test at 5% probability level.
Results and Discussion
Results showed that the interaction of treatments had an effect on fruit weight loss percentage, firmness, and antioxidant activity, chlorophyll and total soluble solids. Thus, the highest percentage of fruit weight loss was observed in the control treatment (without propolis) in 4°C (5.02%). Foliar application of fruits led to an increase in firmness of fruit tissue with propolis in both concentrations of 4 and 8% compared to the control treatment (no foliar application with propolis) in both temperature treatments. The highest total chlorophyll content was in 8% propolis treatments + temperature of 24 °C (8.96 mg / gfw), treatment of 8% propolis + temperature of 4 °C (8.68 mg/gfw) and treatment of 4% propolis + temperature of 4 oC (7.93 mg/gfw) significantly. In addition, antioxidant activity increased in the treatments of 4 °C+ foliar application with propolis 4 and 8%. In general, although fruits treated with 24 ° C showed more weight loss than 4 °C, the use of both concentrations of propolis improved the above trait, reducing the amount of fruit phenol and tissue firmness and other biochemical traits. Studies have shown that the chemical composition of the propolis samples which a certain breed of bees (Apis mellifera intermissa) made have 17 different chemical compounds. They noted that the main phenolic compound was caffeic acid (0.85 mg·g−1 EAP) and the main flavonol compound was pinocembrin (0.82 mg·g−1 EAP). Significant (P ≤ 0.05) differences were observed in dragon fruit quality when treated with different concentrations of ethanolic extract of propolis (EEP) (0.25, 0.50, 0.75 and 1.0%) and stored at 20 ± 2 °C and 80 ± 5% relative humidity (RH) for 20 days, which matched our results. Passos et al. (2016) reported test panel did not detect significant differences amongst coated and not coated cv. Prata bananas up to six days of storage. Propolis extracts.
Conclusion
In addition to a broad spectrum of antimicrobial activity, contain hydrophobic composites that assist in ameliorating attributes as biodegradable films on fruits.
Reza Najafi; Taher Barzegar; Farhang Razavi; Zahra Ghahremani
Abstract
Introduction: Eggplant (Solanum melongena L.) is an important non-climacteric fruit grown in tropical and subtropical regions. The total production in Iran and world for eggplants in 2018 were estimated 54077210 and 666838 tons, respectively, and Iran ranked fifth in the production of this product. The ...
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Introduction: Eggplant (Solanum melongena L.) is an important non-climacteric fruit grown in tropical and subtropical regions. The total production in Iran and world for eggplants in 2018 were estimated 54077210 and 666838 tons, respectively, and Iran ranked fifth in the production of this product. The health-promoting attributes of eggplant are derived from the phytochemicals with good source of antioxidants (anthocyanin and phenolic acids), dietary fiber and vitamins. Fruit deterioration during long term storage is associated with appearance quality reduction, calyx discoloration, softening and pulp browning caused by the oxidation of phenolic compounds. Hydrogen Sulfide (H2S) is a flammable and colorless gas, that similar to carbon monoxide and nitric oxide, is known as third leading signaling molecule. It has been reported that H2S play an imperative role in the postharvest physiology and chilling injury of various fruits and vegetables. In recent years, exogenous phenylalanine (PA) application has been employed as a beneficial procedure for enhancing quality in fruits and vegetables by promoting higher phenols and flavonoids accumulation arising from higher PAL enzyme activity and proline accumulation exhibiting higher ROS scavenging capacity. Thus, the aim of this study was to investigate the postharvest application of H2S and PA on quality and postharvest storage of eggplant fruit during storage at 7 °C for 21 days. Material and Methods: Eggplant fruits (Solanum melongena cv. Hadrian) were harvested at commercially maturity stage in Jun 2019 from a greenhouse in Hashtgerd city, Iran. Fruit selected for uniform size, shape, and color, and immediately transported to the laboratory. They were divided into seven parts for the following treatments: control (0), hydrogen Sulfide (H2S) at 0.1, 0.2 or 0.3 mM and phenylalanine (PA) at 2.5, 5 or 7.5 mM. Each treatment was done in three replicates, consists of 24 fruits from each replicate, and then randomly divided into four groups include six fruits. One group was analyzed 24 hrs. after harvesting and another groups stored at 7 ± 1 °C and 85% RH for 21 days. At 7-day intervals, one group was taken at random and transferred for one day at 20 °C (shelf-life), and subjected to physicochemical analysis. For H2S fumigation, fruit was placed at the bottom of a sealed 15 L container with different aqueous sodium hydrosulfide (NaHS) solution concentrations for 10 min, and for PA treatments, the fruits were immersed in 10 L of fresh phenylalanine solution for 10 min and in distilled water as a control. The fruits were allowed to completely dry at room temperature before storage. Results and Discussion: The results showed that fruits treated by PA and H2S exhibited higher fruit firmness, chlorophyll, anthocyanin, total soluble solids (TSS), vitamin C, pH and titratable acidity (TA) accompanied by lower weight loss and chilling indices during storage at 7 ºC for 21 days. In control eggplant fruits, fruit firmness (24.2%), chlorophyll (45.8%), vitamin C (34.1 %), anthocyanin content (66.2 %) and TA (44.8) decreased, and weight loss (7.5 %), TSS (8.2%) and chilling indices (4.5 %) increased during 21 storage time. The maximum fruit firmness (1.37 and 1.34 kg cm-2), anthocyanin content (5.02 and 4.2 mg L-1) and TA (18.67 and 1.37 %), and the lowest weight loss (3.67 and 3.7 %) and chilling index (1.6 and 1.3 %) was found in fruits treated with H2S at 3 mM and PA at 7.5 mM during storage at 7 °C for 21 days, respectively. It has been reported that texture correlates with firmness and higher firmness is a characteristic indicator of good texture during postharvest storage of fresh products. Soluble solid contents, titratable acidity (TA) and sugars have been known as important attributes contributing in overall sensory quality of fruits and vegetables. Development of the chilling injury disorder significantly reduces quality of fruits and vegetables due to diminished consumer’s acceptance. So, start of chilling injury symptoms eventually becomes economically critical postharvest constraint that defines the storage life potential of the products. Decline chilling injury in responses to H2S and PA treatments may resulted from higher ROS scavenging enzymes SOD, CAT, APX and POD activity and proline, phenols and flavonoids accumulation giving rise to conferring chilling tolerance. Conclusion: According to results, PA at 7.5 mM and H2S at 3 mM had the highest positive effect on maintain firmness and fruit quality and reducing weight loss and chilling, therefor postharvest treatment of PA and H2S can be proposed to improve fruit quality and postharvest life during storage period.
Mahshid Ghfouri; Ali Soleimani; Vali Rabiei; Roghayeh Hemmati
Abstract
Introduction: Due to high quality, Iran pomegranate is quite competitive compared to other countries is unrivaled among agricultural products and has great economic importance. Using essential oil is a new idea to reduce postharvest losses and increase the horticultural crop storage life and control ...
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Introduction: Due to high quality, Iran pomegranate is quite competitive compared to other countries is unrivaled among agricultural products and has great economic importance. Using essential oil is a new idea to reduce postharvest losses and increase the horticultural crop storage life and control of fungal infection. In this context, a factorial experiment based on completely randomized design was conducted to study the postharvest spraying of thyme essential oil on storage life and qualitative characteristics of pomegranate fruit (cv. Tarom red skin)
Materials and Methods: Pomegranate fruit (cv. Tarom red skin) was prepared and transferred to University of Zanjan, Horticulture postharvest physiology lab. Treatments were included essential oil of thyme at four levels (0, 500, 1000, 1500 mg/l) and the cold time storage (6 °C and 85% of relative humidity) at three levels (one, two and three months (by four replications. In the first experiment, 180 normal pomegranate fruits were treated with thyme essential oil. In the second experiment, fruits were infected with spores of the fungus Aspergillus niger and then treated with essential oil. During experiment, total soluble solids (TSS), titratable acidity (TA), TSS/TA ratio, pH, anthocyanin, electrolyte leakage, chilling injury, weight loss and fungal decay were evaluated. Fruit juice TSS was determined with a hand-refractometer at room temperature. TA was determined by titration an aliquot (20 mL) of the juice with 0.1 N NaOH and the results were expressed as a percentage of citric acid. The maturity index (TSS/TA ratio) was evaluated as the TSS/TA ratio. Fruit juice pH was measured using a pH meter. Anthocyanin was performed to method Fuleki & Francis. Electrolyte leakage was measured according to McCollum & McDonald method. Weight loss was measured according to Ershadi method. Chilling injury was measured by Wang method. Decay was visually evaluated and expressed as percentage. An analysis of variance was used to analyze difference between treatments and the Duncan test was applied for mean separation at p
Hamideh Rastegari; Ali Tehranifar; Seyyed Hossein Nemati; Mohammad Reza Vazifehshenas
Abstract
To investigate the effect of different concentrations (0, 0.01% and 0.02%) of salicylic acid (SA) on some quantitative and qualitative characteristics of pomegranate fruit cultivar ‘Malase Yazdi’ at ripening,2 and 4month ofstorageat5°C, a factorial experiment based on randomized complete block with ...
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To investigate the effect of different concentrations (0, 0.01% and 0.02%) of salicylic acid (SA) on some quantitative and qualitative characteristics of pomegranate fruit cultivar ‘Malase Yazdi’ at ripening,2 and 4month ofstorageat5°C, a factorial experiment based on randomized complete block with three replications was conducted. Quantitative characteristics including percentage of fruit weight loss, percentage of healthy arils, aril paleness percentage, and fruit quality characteristics including percentage of skin browning and white segments separating the arils (membrane), electrolyte leakage (EL), juice pH, titrable acidity, total soluble solids, antioxidant activity, juice ascorbic acid content and fruit taste index were measured. The results showed that with time until two month of storage, the weight loss of fruit had happened, but then the rate of weight loss reduced. With SA application percentage of healthy arils and aril paleness increased. The lowest and highest percentage of membrane browning was related to concentration of 0.01% of SA after two month of storage (14.8%) and control fruits after four months of storage (96.6%), respectively. SA in 0.02% concentration reduced EL at harvest but with time the EL increased so that SA could not prevent EL increases after 4 month of storage. Also fruit taste index reduced with increasing in SA concentration. Over time and during storage titrable acidity, total soluble solids, juice PH and browning percentage increased significantly while ascorbic acid decreased.
Yahya Selahvarzi; Ali Tehranifar
Abstract
Fruit spoilage of pomegranate is one of the most important problems in postharvest stages and its exports. This decay is mainly due to the influence and spread of saprophytic or parasitic fungi into the pomegranate fruits. In this purpose effects of essential oil from medicinal plants include; caraway ...
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Fruit spoilage of pomegranate is one of the most important problems in postharvest stages and its exports. This decay is mainly due to the influence and spread of saprophytic or parasitic fungi into the pomegranate fruits. In this purpose effects of essential oil from medicinal plants include; caraway (Carum carvi) and peppermint (Mentha piperetta), and packaging (whit or no polyethylene bags) were investigated on shelf life, quality, decay percentage, chilling index and biochemical traits. The pomegranate fruits were kept in 5±1ºC and 85-90 percent humidity. The results showed that the highest amount of chilling index and weight loss was in without polyethylene bag treatment by 3.45 and 17.03, respectively. On the other hand the most percent of fungal infection was observed in polyethylene alone treatment by 29.41%. Whereas, essential oils (1000 ppm) of caraway and peppermint was able to control postharvest fungal infection caused by LDPE packaging, completely. The usage of caraway essential oil on pomegranate fruits increased phenolic compounds and antioxidant activity, significantly.
