Cold Storage Period Research Articles

Effect of cold storage on development and demographic parameters of Scolothrips longicornis fed on two-spotted spider mite.

Cold storage effects on the female predatory thrips Scolothrips longicornis Priesner (Thysanoptera: Thripidae) fed on Tetranychus urticae Koch eggs for different time periods (5, 10, 20 and, 30 days) at 5 or 25 °C (control) on development and life table parameters were examined. Female adult duration and female total longevity were not influenced by the period of cold storage. The minimum mean female total longevity (28.1 ± 0.32 day) was observed in the 30-day treatment. The oviposition period decreased with increasing cold storage duration. All life table parameters of S. longicornis demonstrated a significant difference across treatments. Our results demonstrated that the female adult of S. longicornis could be maintained at 5 °C for 5-days with minimal reduction in the life-history process. This would be beneficial in the storage and mass production of S. longicornis in biocontrol programs involving T. urticae.

Effects of different Philosamia ricini (Lepidoptera: Saturniidae) cold storage periods on Ooencyrtus pityocampae and Ooencyrtus kuvanae (Hymenoptera: Encyrtidae) rearing.

Ooencyrtus pityocampae and Ooencyrtus kuvanae are egg parasitoids that are considered potential candidates for the control of different pest species through inundative release. The aim of this study was to assess the effects of different cold-storage periods of Philosamia ricini eggs (host) on the rearing parameters of O. pityocampae and O. kuvanae. Host eggs were stored at 3 °C, and a factorial experiment involving two parasitoid species, nine host storage periods (1, 5, 10, 15, 30, 45, 60, 75 and 90 days) and a control, and two host ages (1 and 2 days) was conducted, with 10 replications including 40-P. ricini eggs each. Adult emergence, development time, longevity, and fecundity were investigated. The parasitoid adult emergence percentage significantly varied with storage duration. These values were lower in O. kuvanae than in O. pityocampae. The development time of O. kuvanae progeny increased in both host age groups except in the 1-day storage period subgroup. However, the development times of the progeny of O. pityocampae reared on one-day-old eggs stored for 5, 10, 60, and 75 days were increased, and the development times of the progeny of O. pityocampae reared on 2-day-old eggs stored for 45 and 90 days were increased. The longevity of the F1 progeny of O. kuvanae was negatively affected by storage time. There was no difference in the longevity of the F1 progeny of O. pityocampae compared to that of the control. Additionally, the fecundities of the F1 progeny of O. pityocampae and O. kuvanae were 54.7 and 47.0 offspring/female, respectively. These results provide useful information for guiding the development of mass rearing methodologies for both parasitoid species.

Effects of cold storage and salinity on Acartia sinjiensis (Copepoda: Calanoida) egg hatching

We determined the combined effects of salinity (10, 15, 20, 25, 27, 30 and 33 psu) and cold storage (4 ± 1°C) for 5, 14, 90 and 180 days for extending the lifespan of subitaneous eggs of the calanoid copepod Acartia sinjiensis. The hatching success rate of the eggs decreased with an increase in the cold storage period. The average proportion of viable A. sinjiensis eggs after 90 days was >40% except at a salinity of 10 psu. Eggs hatched at different times depending on storage and salinity. Specifically, >55% of the eggs stored for 14 days under the salinities of 25 and 30 psu and >45% of those stored for 90 days with salinities of 30 and 33 psu hatched. However, some eggs stored for 180 days hatched which only occurred at salinity 30 psu. These results can help optimize cold storage conditions to improve the viability of stored copepod eggs.

Effect of Some Edible Coating Materials On Quality and Storability of Cherry Tomato Fruits During Cold Storage and Shelf Life Periods

This research was conducted in the Post-Harvest Laboratory of the Horticulture Department, Faculty of Agriculture, Zagazig University, Egypt, during two seasons of 2019 and 2020 to study the effect of dipping cherry tomatoes fruits in solutions of edible materials on fruits quality and storability during storage at 7±2°C and 90 ± 3% relative humidity for 28 days. Where the fruits were dipped in chitosan nano particles (ChNPs) solution at 0.5 and 1 %, Arabic gum solution at 5 and 10%, bottle gourd seed oil at 0.2 and 0.4 % and distilled water (control). The results showed that, fresh weight losses, fruit decay, total soluble solids (TSS) content, fruit red color value a*and fruit red color value a*/b* increased progressive as the storage duration was extended from zero to 28 days. On the other hand, increasing the cold storage time reduced the fruit firmness, titratable acidity, vitamin C content and fruit red color value b*. Dipping in solution of bottle gourd seed oil at 0.4% gave the highest fruit firmness, vitamin C and the lowest values of weight loss percentage, Also, dipping in bottle gourd seed oil solution at 0.2 and 0.4 % did not show any decayed fruits and gave the highest values of a*/b*ratio, in addition, it is increased TSS in fruits at 28 days of storage. In general, ChNPs solution at 1 and Arabic gum solution at 10% % gave the highest values of titratable acidity.

Preservation of Nitric Oxide Synthase Activity Required for Beneficial Effects of Hypothermic Oxygenated Perfusion in Cardiac Grafts Obtained with DCD

<h3>Purpose</h3> Cardiac donation after circulatory death (DCD) is a promising option to increase graft availability. We recently reported that cardiac graft preservation with hypothermic oxygenated perfusion (HOPE) between graft procurement and normothermic reperfusion improves graft recovery as compared to preservation with cold static storage (CSS), the current clinical standard. As the precise mechanisms remain incompletely characterized, we investigated the role of preserved nitric oxide synthase (NOS) activity during HOPE on its beneficial effects. <h3>Methods</h3> Using an adult rat model of DCD, hearts underwent in-situ ischemia (21 minutes), were explanted for a cold storage period (30 minutes), and then reperfused under normothermic conditions (60 minutes) with left ventricular loading. Three cold storage conditions were compared: CSS, HOPE, and HOPE with L-NAME (NOS inhibitor). To evaluate potential confounding effects of high coronary flow during early reperfusion in HOPE hearts, bradykinin (BK) was administered to normalize coronary perfusion to HOPE levels in two additional groups (CSS and HOPE with L-NAME). <h3>Results</h3> Cardiac recovery was significantly improved in HOPE vs. CSS hearts, as determined by cardiac output, left ventricular work (heart rate-developed pressure product), contraction and relaxation rates, as well as coronary flow and oxygen efficiency (oxygen consumption per work performed; p<0.05). Strikingly, the addition of L-NAME during HOPE largely abolished its beneficial effects, even when early reperfusion coronary flow was normalized to HOPE levels with BK. Furthermore, preliminary experiments demonstrate a tendency for reduced release of cell death markers in hearts treated with HOPE compared to all other groups. <h3>Conclusion</h3> HOPE provides superior preservation of ventricular and vascular function, as well as improved metabolic recovery, compared to the current clinical standard (CSS). Importantly, preservation of NOS activity during the cold storage period is required for the protective effects of HOPE. The application of HOPE prior to normothermic reperfusion is a promising approach to help optimize cardiac graft recovery following warm ischemia in DCD cardiac grafts.

Ethylene and abscisic acid play a key role in modulating apple ripening after harvest and after cold-storage

An autocatalytic burst in ethylene production generally accompanies ripening of detached apple fruit. However, if apples are left to ripen attached to the tree, some cultivars, will not experience this autocatalytic ethylene production and the fruit will never acquire the organoleptic properties of detached ripened fruit. Accordingly, the present study aimed to understand how the hormonal crosstalk regulates ripening in ‘Golden Reinders’ apples, ripened on-tree, detached from the tree or after a period of cold storage, following the commercial harvest date. Our results showed that during on-tree ripening, ethylene production remained low, and no significant changes were observed in fruit colour or firmness. In fruit ripened detached from the tree, ethylene production was preceded by an increase of indole 3-acetic acid (IAA) and gibberellic acid (GA3) levels, whereas a cold-induced accumulation of jasmonic acid (JA) seemed to induce an earlier initiation of the climacteric burst in fruit ripened after cold storage. In both postharvest conditions, the accumulation of abscisic acid (ABA) may be either needed or facilitating the action of ethylene on triggering some ripening-related changes, pointing out the importance of both hormones in mediating apple ripening. In contrast, changes in sugars and ROS/antioxidants did not vary among the different ripening scenarios suggesting that none of the measured compounds may act as signalling molecules during apple ripening. Collectively, our results highlight that ethylene together with ABA played a crucial role in triggering ripening-related changes during postharvest ripening of ‘Golden Reinders’ apples.

Cold storage demand for 'Rocha' pear ripening: A comparison between a shorter and longer cold period

'Rocha' pear is a cultivar that when harvested at the recommended maturity stage (physiological condition that allows resisting to prolong cold storage), requires chilling exposure after harvest, to induce an autonomously ripening appreciated by the consumer. Fruit were stored immediately after harvest, for 6 d (batch 1) or 26 d (batch 2), in normal cold atmosphere storage, to further our understanding of 'Rocha' pear ripening under different short cold storage durations. The ripening events were then monitored at 0, 3, 7, and 10 d of shelf-life at room temperature (± 20 °C) through physicochemical and biochemical changes, including firmness, soluble sugars, malic acid, esters profile, and ethylene metabolism (1-aminocyclopropane-1-carboxylic acid (ACC) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO)). We found that ripening behaviour upon rewarming from both cold storage periods was similar, with fruit ripening with a typical pattern of ethylene production and respiration rates concomitant with a higher ACO activity. Soluble sugar and esters emission were not influenced by cold storage duration, but interestingly butyl acetate levels were significantly higher on pear, which was cold stored for 26 dOur data provide more novel information about Rocha' pear's ripening physiology, indicating for the first time that approximately one week of chilling temperature is enough to promote ripening rate processes. Such knowledge could be an asset to the efficient management of 'Rocha' pear storage.

Physicochemical and Storage Characteristics of Pork Tteokgalbi Treated with Boesenbergia pandurata (Roxb.) Powder

This study investigates the physicochemical and storage characteristics of Tteokgalbi treated with various concentrations of Boesenbergia pandurata (Roxb.) powder (BP). BP is constituted mainly of carbohydrates (77.9%), possesses free-radical scavenging activity due to the presence of polyphenol and flavonoids, and is slightly acidic (pH 5.99). Five Tteokgalbi samples were treated with 0 (CON), 0.5% (B1), 1.0% (B2), or 2.0% (B3) of BP or 0.05% of ascorbic acid (REF). Compared to CON, BP-treated Tteokgalbi demonstrated significantly higher carbohydrate content and water-holding capacity and decreased cooking loss (%). BP-treated Tteokgalbi had significantly altered Hunter color properties, with decreased L* and increased b* values. Additionally, BP treatment significantly changed the textural properties by increasing the hardness (B3) and chewiness (B2 and B3) and decreasing the springiness (B3) of Tteokgalbi. Owing to the increased total polyphenol and flavonoid content, BP addition significantly enhanced the DPPH and ABTS radical scavenging activities of Tteokgalbi during vacuum-packed cold storage (0–14 days) at 5 °C. BP-treated Tteokgalbi maintained a higher pH compared to CON, and BP-treatment significantly suppressed 2-thiobarbituric acid, volatile basic nitrogen, and total microbial count during the cold storage period (7 and 14 days). Therefore, BP is a natural, edible antioxidant that may be applied to Tteokgalbi.

Effects of the Use of Different Temperature and Calcium Chloride Treatments during Storage on the Quality of Fresh-Cut "Xuebai" Cauliflowers.

This study revealed the effect of the use of different temperature and calcium chloride (CaCl2) treatments on the storage quality of fresh-cut “Xuebai” cauliflowers. Fresh-cut “Xuebai” cauliflowers were soaked with 2% CaCl2 solution at different temperatures. The change in the firmness, color, and ascorbic acid (ASA), total glucosinolates (TGLS), polygalacturonase (PG), and lipoxygenase (LOX) content of fresh-cut “Xuebai” cauliflowers during the cold storage period was assessed. In addition, the sensory quality was also evaluated. The results show that the combined treatments with CaCl2 at different temperatures could effectively maintain the storage quality of fresh-cut “Xuebai” cauliflowers. Then, a method based on factor analysis with comprehensive quality evaluation was proposed. A factor analysis with a principal component analysis (PCA) was conducted on nine indicators of cauliflowers. Two principal components were extracted with a cumulative contribution rate of 97.513%. The results demonstrated that the treatment with the best fresh-keeping effect of cauliflowers in storage was the combination treatment at 40 °C with 2% CaCl2 solution, while the optimal storage period was 15 days.

The Role of Water Relations and Oxidative Stress in the Vase Life Response to Prolonged Storage: A Case Study in Chrysanthemum

Long storage periods have been associated with decreased vase life. In this study, the processes underlying the vase life response to prolonged storage were investigated, along with the potential of light reflectance profiles to estimate storage duration. Three cut chrysanthemum cultivars were exposed to four cold (5 °C) storage periods (0, 7, 14, and 21 d). Stomata were present on the leaves (either side) and stem, but not on petals. As compared to the leaves, stomata on the stem were non-functional, smaller, and less dense. Floral transpiration was a small portion of the whole-cut flower transpiration, with the major contributor being the leaves or stem depending on the cut flower hydration. Storage duration linearly decreased vase life, with the rate of decrease being cultivar specific. Storage duration (0–21 d) did not affect leaf stomatal functioning, non-leaf tissue transpiration, or the relative contribution of each organ to the whole-cut flower transpiration. Cut flower hydration was generally enhanced by storage, while water uptake restoration ability was not impaired. Membrane lipid oxidation increased in response to storage duration owing to enhanced H2O2 accumulation. A strong correlation between membrane lipid oxidation level and the vase life response to cold storage was apparent. By examining the light reflectance profiles (400–1050 nm) of leaves (either side) and flowers (top view), an indication of the storage period could not be deduced. In conclusion, cultivar differences in vase life response to cold storage were attributed to variation in oxidative state, whereas cut flower water relations are clearly not involved.

Effects of Modified Atmosphere Packaging and Methyl Jasmonate Treatments on Fruit Quality and Bioactive Compounds of Apricot Fruit during Cold Storage

The study was carried out to investigate the effects of methyl jasmonate (MeJA) [0.5 and 1.0 mmol L-1] and modified atmosphere packaging (MAP) treatments on weight loss, respiration rate, firmness, colour, soluble solids content (SSC), titratable acidity, vitamin C, total phenolics, flavonoids and antioxidant capacity (DPPH and FRAP assay) of apricot fruit (Prunus armeniaca) during cold storage. Fruit were stored at 0±0.5˚C and 90±5% relative humidity (RH) for 20 days, and analysis and measurements were performed at 5-day intervals. At the end of cold storage, the lowest weight loss was determined in fruit stored with the MAP following MeJA1 application. The lowest respiration rates were determined in fruits stored with the MAP following MeJA1 or MeJA2 treatment. The softening of fruit stored without the MAP or MAP was significantly delayed with the MeJA. The fruit stored without the MAP or MAP following MeJA2 treatment had the highest vitamin C at the end of storage period. MAP treatments had greater total phenolic and total flavonoids and antioxidant capacity than the treatment without MAP regardless of MeJA applications. At the end of storage, the highest total phenolic and antioxidant capacity were determined in fruits stored in the MAP following MeJA2 application. It was concluded that MAP and MeJA2 treatments could be used as an efficient postharvest tool to minimize quality losses throughout the cold storage period.

Biochemical Composition and Antioxidant Activity of Different Types of Tomatoes Affected by Ethylene Treatment

The effect of ethylene on biochemical composition and antioxidant activity in beefsteak, heirloom and cluster type of tomatoes were determined. For that purpose, tomato fruit were harvested at breaker maturity stage and divided into two groups one of which was applied with 150 μL L−1 ethylene while another remained untreated. Ethylene treated and untreated control fruit were stored at 12 °C and 90+5% relative humidity for 35 days with subsamples removed every 7 days for quality analysis. After each removal time, fruit were kept at 20 °C for additional 3 days to determine shelf life performance. Ethylene treatment enhanced the breakdown of total chlorophyll and accumulation of lycopene and carotenoid contents. At the end of cold storage and shelf life period, the maximum antioxidant activity, carotenoid and flavonoid contents were recorded in ethylene treated heirloom type tomatoes. It can be concluded that ethylene treated heirloom type tomatoes exhibited maximal postharvest quality as compared to beefsteak and cluster type of tomato in term of biochemical composition and antioxidant activity after 35 days of cold storage and shelf life.

Postharvest performance interpretation and storage temperature optimization in some newly introduced melon hybrids

Temperature is a key factor in melon cold storage. Thus, optimizing storage temperature is an important goal in postharvest research. In this experiment, postharvest attributes of four inbred lines and five derivative hybrids were investigated under three storage temperatures (1, 4, and 12°C). Melon fruit were evaluated for their main characteristics directly after harvest and postharvest changes were monitored through cold storage period. Cluster analysis results showed that most of the hybrids clustered with their maternal parents illustrating the significant role of cytoplasmic inheritance for the studied traits. Similarly, principal component analysis clustered the studied types into three clusters according to their average postharvest behaviour. The best postharvest performance belonged to inodorus and cantalupensis netted melon with their intercrossing breeds. While the dudaim inbred line and its hybrid scored the highest postharvest changes. Response surface analysis showed that 1.8°C was the optimum storage temperature for inodorus and cantalupensis clusters, while 5.1°C was the best storage temperature of dudaim cluster. The results of the current study are similar to previous reports for optimum storage temperature in similar melon types.

Survivability of probiotic strains, Lactobacillus fermentum CECT 5716 and Lactobacillus acidophilus DSM 20079 in grape juice and physico-chemical properties of the juice during refrigerated storage

In this study, non-fermented probiotic grape juices were produced with the inoculation of two different strains of lactic acid bacteria (Lactobacillus fermentum CECT 5716 and Lactobacillus acidophilus DSM 20079) separately. The viability of probiotic microorganisms, as well as the grape juices’ physicochemical properties were evaluated throughout 21 days of storage at 4 °C. In grape juice, both strains had similar survival rates, and viable cell counts remained above the recommended therapeutic minimum (107 CFU mL-1) throughout the monitored storage time. Both of the probiotic samples showed a drop in pH, total phenolic content and viscosity during storage, as well as an increase in acidity. The values of lightness, redness, and yellowness in grape juice containing L. acidophilus DSM 20079 were reduced over cold storage period; otherwise, color characteristics for the control and sample with added L. fermentum CECT 5716 were maintained. This study showed that grape juice is an effective vehicle for delivering the Lactobacillus strains studied, with their probiotic activity remaining for 21 days at 4 oC, making it a probiotic beverage alternative for non-dairy product users. Furthermore, L. fermentum CECT 5716 can be more suitable due to its maintenance of color properties in grape juice over the storage.

Effects of maternal vitamin D3 status on quality characteristics of pork batters in offspring pigs during cold storage

Seventy-two offspring pigs (150 d) from 27 sow (9 sows per group) fed different vitamin D3 levels were used to evaluate the effects of maternal vitamin D3 status and postmortem cold storage on cooking loss, color, texture profile analysis (TPA), low-field nuclear magnetic resonance (LF-NMR) T2 relaxation times and dynamic rheological of gel properties of chilled pork batters in offspring pigs. Sows were allotted to low, normal, and high dietary vitamin D3 groups which contained 200 (LD), 800 (ND), and 3200 (HD) IU of vitamin D3/kg basal diet, respectively. Results showed that HD group had higher a* value, hardness, cohesiveness, springiness, chewiness, and storage modulus (G') values, while had lower cooking loss, L* value, T21 and T22 relaxation time compared with LD group during postmortem cold storage period (P < 0.05). In addition, cold storage time increased cooking loss and b* values of LD and ND groups, TPA parameters, T22 relaxation time and G' values of all experimental groups, while decreased a* and L* values of LD and ND groups (P < 0.05). The results revealed that maternal high-dose vitamin D3 levels influenced these indicators of chilled pork batters in offspring pigs, which improved the quality attributes during postmortem cold storage.

저온 저장이 레드키위 과실 품질에 미치는 영향

This studies was conducted to investigate the effect of cold storage on red kiwi fruit quality by cultivar. As a result of investigating the firmness and acidity of fruit after cold storage, the firmness and acid content decreased in all cultivars, and sugar content increased in all cultivars. The reason for the decrease in acid content during cold storage of kiwi is that it is converted from organic acid to sugar and used for breathing. And the reason for the increase of The total soluble solids (TSS) during storage is that it is converted from starch to sugar. ‘Hongyang’ had a commodity rate of 94.4% and a non-commodity of 5.6% on February 5, 110 days after storage. ‘EnzaRed’ had a commodity rate of 93.9% and a non-commodity of 6.1% on January 15, 89 days after storage. ‘QiHong’ had a commodity rate of 94.8% and a non-commodity rate of 5.2% on February 23, 113 days after storage. The appropriate cold storage period for each culrivar is considered to be 110 days for ‘Hongyang’, 89 days for ‘EnzaRed’, and 113 days for ‘QiHong’.

Enhancement of Selected Health Benefits in Fermented Cow and Soy Milk Supplemented with Water Soluble Curcumin

Different formulates of fermented cow and soy milk by Lactobacillus plantarum EMCC 1027 with 50, 100, and 150 mg/100 mL curcumin were investigated for antibacterial, antioxidant, anti-colonic cancer, and anti-inflammation activities. Also, the viability of L. plantarum was monitored during cold storage period. Our results showed that values of antibacterial, antioxidant, anti-colonic cancer, and anti-inflammation activities in crude extracts of fermented soy milk were significantly increased in comparison with crude extracts of fermented cow milk. The addition of different concentrations (100 and 150 mg/100 mL) of curcumin had a significant enhancement effect for all selected health benefits properties. The increase in antioxidant capacity of different crude extracts was in a good correlation with their polyphenols content. Addition of water soluble curcumin did not have any adverse effect on the viability of L. plantarum during fifteen days of cold storage. Therefore, the synergistic effect between fermented cow/soy milk and water soluble curcumin could be recommended. Indeed, extensive research is still needed in order to investigate the molecular mechanisms of health a benefit of different formulates of fermented cow/soy milk and water soluble curcumin.

Inulin Clearance During Ex vivo Normothermic Machine Perfusion as a Marker of Renal Function.

Normothermic machine perfusion (NMP) offers a unique opportunity to objectively assess donor organ quality. This study describes the evaluation of inulin clearance as a potential marker for the ex vivo function of porcine kidneys during NMP. The function assessment was performed in both kidneys from slaughterhouse pigs (n = 20) and kidneys from pigs in a laboratory setting (n = 28). The kidneys were exposed to different warm ischemia times (WIT). After a period of static cold storage, the kidneys underwent a 4-hour NMP with autologous whole blood. Inulin clearance, hemodynamic parameters, and urine output were measured. Based on the inulin excretion behavior laboratory pig kidneys were assigned to three classes (functional, limited functional, and nonfunctional), slaughterhouse pig kidneys to two classes (limited functional and nonfunctional), respectively. Contrary to the marginal kidneys of the slaughterhouse pigs, the functional variation of kidneys of the laboratory pigs was associated with the WIT. A correlation between functional kidneys and a WIT less than 25 min was shown. Because none of the slaughterhouse pig kidneys could be assigned to the functional class, only the laboratory pig kidneys were used for examinations with functional markers. Renal blood flow and urine output during NMP correlated significantly ( p < 0.01) with ex vivo kidney function. This study demonstrated that inulin is a marker of high quality for the evaluation of suggested kidney function after NMP with whole blood. Furthermore, surrogate markers measured during NMP can be used to describe and predict the physiologic behavior of kidneys before transplantation.

Impact of Hot Water and Modified Atmosphere Packaging Treatments on the Postharvest Quality of Pomegranate Fruit cv. Hicaznar

Hot water (HW) and modified atmosphere packaging (MAP) treatments were evaluated to maintain postharvest quality of pomegranate fruit (Punica granatum cv. ‘Hicaznar’). Pomegranates were subjected to hot water (HW) treatment (at 50 °C for 3 min) and packaged with or without MAP bags. Fruit was then kept at 6 °C for 6 months and at 20 °C for 7 days after cold storage period. The untreated and unpackaged fruit was served as a control treatment (C). MAP and HW+MAP treatments was more effective in reducing weight loss, fungal decay and husk scald, compared to HW and C treatments. The lightness and red color intensity of husk and aril (higher values of L* and C* and lower values of h°) were maintained better in the packaged fruit with MAP (MAP + HW+MAP treatments). The unpackaged fruit from HW and C treatments became unmarketable while those from MAP and HW+MAP treatments were still marketable after 6 months of cold storage and shelf life period. Although fungal decay incidence was low in HW-treated fruit, relatively high scald incidence and weight loss had adverse effect on overall visual acceptability of HW-treated fruit. Hot water dipped pomegranate fruit cv. ‘Hicaznar’ (50 °C for 3 min) could be kept in MAP bags for 6 months at 6 °C and for 7 days 20 °C without adverse effect on quality.

Comparison of Ethylene Sensitivity of Three Tomato Cultivars From Different Tomato Types and Effects of Ethylene on Postharvest Performance

The aim of study was to investigate ethylene sensitivity of different types of tomatoes and the effects of ethylene on their postharvest performance. For that purpose, beefsteak, heirloom and cluster types of tomato fruit were harvested at the breaker maturity stage and divided into two groups one of which was treated with 150 μL L−1 ethylene and the other was untreated for comparison. Ethylene treated and untreated fruit were stored at 12 °C and 90+5% relative humidity for 35 days and subsamples removed every 7 days for postharvest quality analysis. After each removal time, fruit were kept at 20 °C for 3 days in order to determine shelf life performance. Ethylene treatment lead to increase respiration rate, ethylene production, weight loss but decreased fruit firmness in all tested tomato cultivars. Minimum ethylene production and respiration rate occurred in untreated beefsteak tomatoes. At the end of cold storage and shelf life period, the highest L* values and fruit firmness were recorded for control beefsteak tomatoes. The conclusion drawn from this experiment was that the cluster type of tomatoes was more sensitive, while beefsteak type of tomatoes was found to be less sensitive to ethylene treatment as they had the highest and lowest amount of ethylene productions respectively. Untreated beefsteak tomatoes exhibited maximal postharvest quality compared to other treatments after 35 days cold storage and shelf life.