Effect of pre‐harvest salicylic acid spray treatment on post‐harvest antioxidant in the pulp and peel of ‘Cara cara’ navel orange (Citrus sinenisis L. Osbeck)

BACKGROUND: Exogenous salicylic acid (SA) pretreatment could change the antioxidant system and maintain the nutritional value of fruits and vegetables, which have a higher ability to withstand oxidation injuries. However, the relationship between a pre‐harvest SA spray and post‐harvest antioxidant compounds in fruit remains unknown. RESULTS: The post‐harvest behaviour of antioxidant compounds in ‘Cara cara’ navel orange (Citrus sinenisis L. Osbeck) fruit was investigated in relation to the pre‐harvest SA applications. Pre‐harvest SA treatment significantly increased the content of carotenoids (lycopene and α‐carotene), ascorbic acid, glutathione, total phenolics, and total flavonoids in the pulp and peel during storage. Furthermore, the values of these antioxidant compounds were high in the fruit treated with high SA concentrations (1.0 and 2.0 mmol L^?1). High antioxidant activity was also observed in the SA pre‐harvest treated fruit when compared with the control. The positive relationships were found between the antioxidant activity and the content of these active compounds. CONCLUSION: These results indicated that SA could maintain fruit antioxidant activity and nutrition which was shown by the increase in content of antioxidant compounds and suggested that pre‐harvest treatment with SA promised a novel technology, which was a substitute for the perplexing programme control of post‐harvest nutrition in fruit. Copyright © 2007 Society of Chemical Industry     

Effects of a chitosan‐based coating with ascorbic acid on post‐harvest quality and core browning of ‘Yali’ pears (Pyrus bertschneideri Rehd.)

BACKGROUND: Chitosan (CTS), as an ideal coating material, has been used for post‐harvest treatment of fruits and vegetables. The effects of coating with 1.5% CTS, alone or combined with 10 mmol L^?1 ascorbic acid (AsA), on post‐harvest quality and core browning (CB) incidence in ‘Yali’ pears during storage at room temperature (25 ± 1 °C) were investigated in this study. RESULTS: It was found that both CTS coating and CTS + AsA coating delayed the increase of weight loss, retained greater firmness, total soluble solids and titratable acidity content than controls; coatings decreased respiration rate and membrane permeability, and also effectively inhibited CB after 60 days of storage. Compared with CTS coating alone, CTS + AsA coating increased these beneficial effects and also helped to retain a much higher AsA content and the activities of antioxidative enzymes (superoxide dismutase, catalase and ascorbate peroxidase). CONCLUSION: The CTS coating has the potential to maintain post‐harvest quality and control CB which is the main problem in ‘Yali’ pears during storage. The CTS + AsA coating has more effective application in this study, which could not only be due to reducing the respiration rate and inhibiting the senescence process, but also to increasing the antioxidant capability of the fruit. Copyright © 2008 Society of Chemical Industry     

Enhanced preservation effects of sugar apple fruits by salicylic acid treatment during post‐harvest storage

BACKGROUND: Salicylic acid (SA) is recognised as an endogenous signal, mediating in plant defense and against pathogens. It has been reported that SA treatment can reduce decay and extend storage life of various fruit, such as bananas, peaches and apples. RESULTS: Physiological and biochemical responses in harvested sugar apple fruit (Annona squamosa L.) to SA at 0.4, 0.8 and 1.2 mmol L^?1 were investigated during post‐harvest storage. Results indicated that SA treatments lowered respiration, increased activities of antioxidant enzymes of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX), decreased lipoxygenase (LOX) activity and correspondingly lowered Malondialdehyde (MDA) contents in treated fruits was observed as compared to the control. Moreover, production of superoxide free radical (O₂^{?, ?}) and ethylene was significantly decreased in the treated fruits. Total soluble solids, total soluble sugar, softness and decay rate were significantly lowered in treated fruits, and in turn a delay in the fruits ripening process was achieved after 10 days of storage. CONCLUSION: SA has positive effects in maintaining membrane integrity and in delaying fruit ripening process, which results in improved storability of sugar apple. Copyright © 2008 Society of Chemical Industry     

Changes in physicochemical and nutritive parameters and bioactive compounds during development and on‐tree ripening of eight plum cultivars: a comparative study

BACKGROUND: There is no literature on changes in organoleptic, nutritive and functional properties during plum development and on‐tree ripening. In this work a comparative study on the evolution of physical, chemical and nutritive parameters and bioactive compounds of eight plum cultivars (yellow and dark‐purple) was performed. RESULTS: The main changes related to ripening (colour, total soluble solids, acidity, firmness and bioactive compounds) started at the early stages of fruit development, with significant differences among cultivars. Colour hue angle was highly correlated with increase in anthocyanins or carotenoids (in both skin and flesh). Total antioxidant activity (TAA) was determined in the hydrophilic (H‐TAA) and lipophilic (L‐TAA) fractions separately, and values were always higher in the skin than in the flesh. A continuous increase in both H‐TAA and L‐TAA during the process of ripening occurred. H‐TAA was about twofold higher than L‐TAA in the dark‐purple cultivars, while the opposite was found in the yellow cultivars. In addition, H‐TAA was correlated with total phenolics and total anthocyanins, while L‐TAA was positively correlated with total carotenoids. CONCLUSION: In order to achieve the optimal organoleptic, nutritive and health‐beneficial properties of plum consumption, it would be advisable to harvest the fruits at the fully ripe stage. Copyright © 2008 Society of Chemical Industry     

Increased ethylene biosynthesis elevates incidence of chilling injury in cold‐stored ‘Amber Jewel’ Japanese plum (Prunus salicina Lindl.) during fruit ripening

Mature ‘Amber Jewel’ Japanese plum fruit were stored at 0 or 5 °C for 3 and 6 weeks to investigate their effects on ethylene (C₂H₄) biosynthesis during ripening at ambient temperature in the development of chilling injury (CI) and fruit quality. CI (internal breakdown and browning) and fruit softening were higher during ripening, in the fruit stored at 5 °C than 0 °C, irrespective of storage period (SP). C₂H₄ production and activities of 1‐aminocyclopropane‐1‐carboxylic acid synthase (ACS) and 1‐aminocyclopropane‐1‐carboxylic acid oxidase (ACO) enzymes, and 1‐aminocyclopropane‐1‐carboxylic acid (ACC) content were higher during ripening in fruit stored at 5 °C than 0 °C. The fruit stored at 5 °C also exhibited higher respiration rate and higher soluble solids concentration/titratable acidity ratio. In conclusion, increase in storage temperature and SP elevates the activities of ACS and ACO enzymes and consequently C₂H₄ production which leads to the development of CI in plum fruit with advancement of ripening.     

EFFECTS OF 1‐METHYLCYCLOPROPENE AND MODIFIED ATMOSPHERE PACKING ON POSTHARVEST LIFE AND QUALITY IN TOMATOES

ABSTRACT

The effects of 1‐methylcyclopropene (1‐MCP), modified atmosphere packaging (Xtend, StePac L.A. Ltd., Tefen, Israel) and their combination were investigated on storage and quality maintenance of tomatoes cv. “Perla” harvested at two maturity stages. 1‐MCP treatment was performed in 1,000 nL/L doses for 24 h while untreated fruits were considered as control. Fruits were stored at 12C with 90% relative humidity for 21 days. Weight loss, skin color, elasticity, lycopene, ascorbic acid, soluble solid content (SSC), titratable acidity (TA) and SSC/TA were evaluated with the intervals of 7 days. MAP with and without 1‐MCP reduced weight loss and maintained to elasticity compared with control and 1‐MCP alone. Nevertheless, 1‐MCP or its combination with MAP significantly delayed changes in parameters related to fruit ripening, such as skin color, lycopene, TA and SSC/TA increase in both ripening stages. Overall results indicated that the combination of 1,000 nL/L 1‐MCP and modified atmosphere package was the most effective treatment in both ripening stages.

PRACTICAL APPLICATIONS

Tomato is a climacteric fruit and its ripening depends on ethylene production physiology. 1‐Methylcyclopropene (1‐MCP) prevents ethylene action by blocking ethylene receptors and extends the storage life of tomatoes. Modified atmosphere packaging (MAP) of fresh fruits and vegetables refers to the still evolving technique of matching the respiration of the product with the O₂ and CO₂ permeability of packages in order to modify the oxygen and carbon dioxide concentrations of the atmosphere to desired levels within the package. Recent studies revealed that combined applications of 1‐MCP and MAP have significant effects on maintaining storage quality of banana, litchi and plums. This study was conducted on the investigation of the effects of 1‐MCP and MAP combination on storage duration and quality of tomatoes harvested at different maturity stages.     

Respiration,pectolytic activity and textural changes in ripening African mango (Irvingia gabonensis) fruits

Post-harvest changes in fruit firmness, respiration, pectinesterase (PE) and polygalacturonase (PG) activities were followed in African mango fruits during storage ripening at tropical ambient conditions (28±1°C and 68±2% RH). Respiration followed a climacteric pattern attaining a peak of 99·37 ml CO₂ kg^?1 hr^?1 on the fifth day of storage while full ripeness (colour index—5) was attained on the tenth day. PE and PG activities increased with progressive fruit ripening attaining their optima on the fifth day (1·8 PE unit) and tenth day (27 PG units), respectively. Fruit firmness decreased as pectolytic activity increased with a concomitant reduction in the deformation force from 49 kPa in the unripe fruit to 25 kPa at the edible ripe stage.     

Effect of pre‐ripening chilling temperatures on ripening,shelf life and quality of bananas treated with 1‐methylcyclopropene

Ethylene production, shelf life and fruit quality of Cavendish bananas (cv. Williams), held at different pre‐ripening storage temperatures (5 °C, 10 °C or 15 °C) prior to ethylene and/or 1‐methylcyclopropene (1‐MCP) application, were determined and compared. Levels of ethylene production during ripening were highest for control fruit that had been stored at 5 °C followed by 10 °C and then 15 °C. 1‐MCP treatment (at 300 nL L^?1) had no effect on ethylene production of fruit that had been stored at 10 °C by day 10 of storage, but ethylene production was significantly higher for fruit that had been stored at 15 °C and lower for those stored at 5 °C before 1‐MCP treatment. 1‐MCP also increased shelf life to a greater extent when applied to fruit that had been stored at 10 °C or 15 °C. Even though 1‐MCP had no significant effect on under peel chilling injury, it increased discolouration significantly, regardless of storage temperature. Firmness of 1‐MCP‐treated fruit decreased significantly compared to the control when fruit were held at 5 °C or 15 °C prior to ripening (and 1‐MCP application) but had no effect on fruit stored at 10 °C before ripening. These results indicate that pre‐ripening storage temperature affects ripening, shelf life and quality in both ethylene and 1‐MCP‐treated bananas.     

The effects of fruit maturation,delayed storage and ethylene treatment on the incidence of low‐temperature breakdown of ‘Hayward’ kiwifruit

BACKGROUND: Low‐temperature breakdown (LTB), a disorder inducing quality loss, during and after cold storage of ‘Hayward’ kiwifruit was investigated. Harvested kiwifruits during fruit maturation or after delayed storage (DS) at 20 °C for 0, 1, 2, 3 and 4 weeks and 1 µL L^?1 ethylene treatment for 24 h were stored at ? 0.5 °C for 24 weeks and additional ripening at 20 °C for 5 days. Fruit quality indices and LTB incidence and severity were determined before and after treatments. RESULTS: Harvested fruits ripened during maturation, DS and after ethylene treatment. After storage and shelf life, fruits of all treatments were at complete ripening stage. LTB incidence of early harvested fruits was high, while that of fruits of the mid (third) and late harvests was low. Fruits of the third harvest date showed progressively increased LTB incidence with increasing duration of DS to as high as 95–100% after 4 weeks. Ethylene‐treated fruits showed a comparable increase in LTB to that corresponding to 2–3 weeks of DS. CONCLUSION: In contrast to fruit maturation, postharvest (after harvest and before storage) DS at non‐chilling temperature and ethylene treatment advanced the ripening of ‘Hayward’ kiwifruit and resulted in increased LTB incidence. Copyright © 2012 Society of Chemical Industry     

Effect of native and acetylated‐crosslinked waxy corn starch‐beeswax coatings on quality attributes of raspberries during storage

Edible coatings (ECs) are a thin layer of a mixture of edible materials, applied in the liquid state and dried over the surface of a food product to maintain its quality during storage. This work was aimed to study the effect of ECs made from wx corn starch (WCS) or acetylated cross‐linked starch (ACLS) added with beeswax on fresh raspberry quality attributes during short‐term cold storage. Freshly harvested fruits were coated, dried, packed in plastic trays and stored up to 8 days at 4°C. During storage quality parameters such as firmness, respiration rate, anthocyanins content, total phenols, color changes, and weight loss were evaluated. A clear effect on control of respiration rate was observed in coated raspberries. Respiration rate of uncoated fruit was 4.5 ± 0.28 mmol/kg/h and decreased to 4.2 ± 0.27 for ACLS and to 4.1 ± 0.08 mmol/kg/h for WCS‐coated raspberries, after 56 h of storage at 15°C. Ethylene production followed a similar trend under these conditions decreasing from 0.043 ± 0.005 to 0.034 ± 0.004 mmol/kg/h for uncoated and ACLS coated fruits, respectively, indicating an effect on ripening control. Additionally, ACLS and WCS coatings permitted the preservation of color without affecting anthocyanins content. However, the presence of anaerobic metabolites and reduction of terpenes production in cold stored coated raspberries indicated hypoxic conditions, which can adversely affect shelf‐life quality attributes of raspberries such as firmness and weight loss.     

The post harvest sensory and chemical characteristics of cold‐stored pineapples pretreated with different Fruitone concentrations

The effects of Fruitone CPA [2‐(3‐chlorophenoxy)propionic acid] (0‐44 ppm) on post‐harvest storage, chemical characteristics and sensory evaluation of pineapples for fresh consumption after storage at 10 ± 1 °C were studied. Pre‐harvest Fruitone treatment beneficially affected the physical characteristics of pineapples, namely increased fruit weight, reduced texture loss, reduced crown size and delayed ripening, but adversely affected their chemical characteristics. Almost all parameters analysed (total soluble solid, titratable acidity, pH and sugars) showed that Fruitone concentrations between 35.2 and 44 ppm were most effective in delaying the ripening of pineapples compared to other concentrations. At these concentrations, Fruitone significantly (P < 0.05) reduced the total soluble solid and pH, but significantly (P < 0.05) increased the titratable acidity. Fruitone treatment was effective in maintaining the TSS and reduced the fluctuation of sugar and the sugar–acid ratio during storage and between fruits. Sensory scores showed that there was a slight increase in the score for odour after 3 weeks of storage between Fruitone‐treated pineapples and control pineapples, while all other sensory attributes (sourness, sweetness, flavour and overall acceptability) were insignificantly different. All sensory attributes correlated positively with pH and sucrose at low concentrations of Fruitone (0–8.8 ppm and 0–26.4 ppm, respectively); with glucose at intermediate Fruitone concentration (17.6–26.4 ppm); with total soluble solid at higher Fruitone concentrations (35.2–44 ppm); and with sugar–acid ratio at all concentrations (except at 44 ppm Fruitone). Copyright © 2006 Society of Chemical Industry     

Regioisomeric distribution of 9‐ and 13‐hydroperoxy linoleic acid in vegetable oils during storage and heating

BACKGROUND

The oxidative deterioration of vegetable oils is commonly measured by the peroxide value, thereby not considering the contribution of individual lipid hydroperoxide isomers, which might have different bioactive effects. Thus, the formation of 9‐ and 13‐hydroperoxy octadecadienoic acid (9‐HpODE and 13‐ HpODE), was quantified after short‐term heating and conditions representative of long‐term domestic storage in samples of linoleic acid, canola, sunflower and soybean oil, by means of stable isotope dilution analysis–liquid chromatography‐mass spectroscopy.

RESULTS

Although heating of pure linoleic acid at 180 °C for 30 min led to an almost complete loss of 9‐HpODE and 13‐HpODE, heating of canola, sunflower and soybean oil resulted in the formation of 5.74 ± 3.32, 2.00 ± 1.09, 16.0 ± 2.44 mmol L^–1 13‐HpODE and 13.8 ± 8.21, 10.0 ± 6.74 and 45.2 ± 6.23 mmol L^–1 9‐HpODE. An almost equimolar distribution of the 9‐ and 13‐HpODE was obtained during household‐representative storage conditions after 56 days, whereas, under heating conditions, an approximately 2.4‐, 2.8‐ and 5.0‐fold (P ≤ 0.001) higher concentration of 9‐HpODE than 13‐HpODE was detected in canola, soybean and sunflower oil, respectively.

CONCLUSION

A temperature‐dependent distribution of HpODE regioisomers could be shown in vegetable oils, suggesting their application as markers of lipid oxidation in oils used for short‐term heating. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Effect of delayed storage and continuous ethylene exposure on flesh reddening of ‘Royal Diamond’ plums

BACKGROUND: Flesh reddening has been described as one of the manifestations of plum fruits to low‐temperature storage for prolonged periods. The influence of factors such as ethylene and delayed storage has not been studied to date. In order to assess that, plum cv. ‘Royal Diamond’ fruits were (a) stored at 5 °C (control), (b) held at 20 °C for 2 days before storage at 5 °C (delayed storage) or (c) maintained at 5 °C under 15 µL L^?1 ethylene. Fruits were then transferred to 20 °C and ethylene, respiration, weight loss, firmness, soluble solids content, acidity, flesh reddening, anthocyanin accumulation and phenylalanine ammonia‐lyase (PAL) activity were determined. RESULTS: Delayed storage fruits showed more extensive flesh reddening than control fruits, with increased PAL activity and higher anthocyanin accumulation. Symptoms were expressed more markedly when fruits were stored at 5 °C in ethylene. CONCLUSION: Results indicated that the fruit ripening stage is a critical factor determining the susceptibility of ‘Royal Diamond’ plums to flesh reddening. Fruits continuously exposed to ethylene showed a dramatic increase in reddening, suggesting that ethylene contributes to the development of the disorder. Copyright © 2008 Society of Chemical Industry     

Effects of stage II and postharvest deficit irrigation on peach quality during maturation and after cold storage

Effects of regulated deficit irrigation (RDI) on the quality of a mid–late maturing peach (Prunus persica L Batsch cv Andross) were determined at commercial harvest as well as 1 week before (early pick‐up) and after 1 week of cold storage. Respiration and ethylene evolution were measured during 96 h on fruits sampled at early pick‐up and at harvest. Fruits from a well‐watered irrigation treatment (Control) were compared with a treatment of RDI during stage II of fruit growth (RDI‐SII) and with RDI applied postharvest (RDI‐PH). A fourth treatment received a combination of deficit irrigation applied during stage II and postharvest (RDI‐SII‐PH). Higher soluble solids content (SSC) amd SSC/titratable acidity (TA) ratio for RDI‐SII were already noted at early pick‐up and these differences were enhanced after cold storage (RDI fruits having higher SSC, lower TA and higher SSC/TA ratio than Control fruits). This improvement in quality (high SSC/TA ratio) was also correlated with a more reddish colouration in the fruit skin. Moreover, ethylene production indicated different behaviour of the physiological evolution for fruits from the different treatments. Copyright © 2004 Society of Chemical Industry     

Extending shelf-life of persimmon (<Emphasis Type="Italic">Diospyros kaki</Emphasis> L.) fruit by hot air treatment

‘Qiandaowuhe’ persimmon fruits (Diospyros kaki L.) were stored at 20 °C after exposed to 20 °C (control), 44 °C (T ₄₄), 48 °C (T ₄₈) or 52 °C (T ₅₂) hot air for 3 h, respectively. Firmness, weight loss, peel color, total carotenoids content, soluble solids content (SSC), titratable acidity (TA), respiration, and ethylene production and cell wall hydrolysis enzymes activities were monitored to determine the efficacy of hot air treatment in delaying persimmon fruit ripening. Results showed that ‘Qiandaowuhe’ persimmon fruit displayed a typical climacteric pattern of respiration and ethylene production. Peak of CO₂ and ethylene production was observed after 4 days. Fruit softening was accompanied by a progressive increase in weight loss, total carotenoids content and decrease in h°. The activities of pectinmethylesterase (PME) and polygalacturonase (PG) sharply increased and reached maximal values after 4 and 6 days, respectively. Hot air treatment significantly delayed the onset of climacteric ethylene production, respiration, PME and PG activities in persimmon fruit. Moreover, it also significantly retarded the increase in carotenoids content and SSC, while decreased the firmness, h°, and TA. The hot air treatment promoted fruit weight loss. The shelf-life of persimmon ripening increased 4 days by T ₄₄, and 6 days by T ₄₈ or T ₅₂. Results suggest that hot air treatments can greatly extend the postharvest life of ‘Qiandaowuhe’ persimmon fruit.     

How to prevent ripening blockage in 1-MCP-treated 'Conference' pears

BACKGROUND: Some European pear varieties treated with 1‐methylcyclopropene (1‐MCP) often remain ‘evergreen’, meaning that their ripening process is blocked and does not resume after removal from cold storage. In this work this was confirmed also to be the case in ‘Conference’ pears. To reverse the blockage of ripening 1‐MCP treatments combined with external exogenous ethylene were tested. RESULTS: 1‐MCP treatment of ‘Conference’ pears is very effective in delaying ripening and, more specifically, softening. The same 1‐MCP concentration in different experimental years caused a different response. The higher dose of 1‐MCP (600 nL L^?1) always resulted in irreversible blockage of ripening, whereas the behaviour of fruit receiving a lower dose (300 nL L^?1) depended on the year, and this did not depend on maturity at harvest or on storage conditions. Simultaneous exposure to 1‐MCP and exogenous ethylene significantly affected fruit ripening, allowing significant softening to occur but at a lower rate compared with control fruit. CONCLUSION: The application of exogenous ethylene and 1‐MCP simultaneously after harvest permitted restoration of the ripening process after storage in ‘Conference’ pears, extending the possibility of marketing and consumption. Copyright © 2011 Society of Chemical Industry     

Changes of Bioactive Compounds and Ethylene Production of Japanese Plums Treated with Pre-Harvest Aminoethoxyvinylglycine

The effects of pre-harvest aminoethoxyvinylglycine treatments on bioactive compounds, fruit ripening, and quality of plum fruits (Prunus salicina Lindell cvs. “Black Beauty,” “Black Amber,” and “Friar”) were investigated in this research. Whole trees were sprayed once with an aqueous solution containing aminoethoxyvinylglycine (0, 100, and 200 mg L^–1) two weeks before the anticipated commercial harvest for each cultivar separately. In all plum cultivars, the results showed that aminoethoxyvinylglycine treatments were effective in reducing ethylene production and respiration rate. The red color development was delayed by aminoethoxyvinylglycine treatments during the ripening. The fruit mass and geometric mean diameter significantly decreased, while loss of flesh firmness was decelerated with aminoethoxyvinylglycine concentrations. Aminoethoxyvinylglycine treatments decelerated loss of flesh firmness. Soluble solid content was reduced, whereas titratable acidity and ripening index increased with aminoethoxyvinylglycine treatments. Aminoethoxyvinylglycine-treated fruits exhibited lower levels of total phenolics, total antioxidant activity, and individual phenolics. This study revealed that pre-harvest aminoethoxyvinylglycine treatments were more effective in delaying plum fruit softening. The main advantage is to maintain the firmness of late-harvested fruit by retaining bioactive compounds of plum fruit.     

Influence of different concentrations of 1-methylcyclopropene on the quality of tomato harvested at different maturity stages

BACKGROUND: A wide range of 1‐methylcyclopropene (1‐MCP) concentrations as well as various treatment durations have been studied in tomatoes by different researchers. However, little is known about interaction of 1‐MCP doses and maturity stages of tomatoes. Therefore the effects of different concentrations of 1‐MCP on storage and postharvest quality of ‘Zorro’ tomatoes harvested at mature green or pink maturity stages were investigated in a 2‐year trial study. RESULTS: Higher concentrations of 1‐MCP delayed and/or inhibited all parameters related to fruit ripening, such as lycopene, chlorophyll, surface color, polygalacturonase (PG) activity and soluble solids content/titratable acidity (SSC/TA), and these effects were greater in tomatoes harvested at the mature green stages. Lower concentrations of 1‐MCP slightly reduced the loss in general quality features compared with untreated tomatoes. CONCLUSION: The results suggest that 1‐MCP, especially at higher doses, is effective for delaying ripening of mature green tomatoes. Mature green fruits treated with 1000 nL L^?1 1‐MCP were stored for 35 days without significant decreases in quality characteristics such as elasticity, surface color and SSC/TA with certain physiological processes (ethylene production, PG activity, lycopene synthesis). Copyright © 2011 Society of Chemical Industry     

Delayed harvest and cold storage period influence ethylene production,fruit firmness and quality of ‘Cripps Pink’ apple

The effects of harvest date and cold storage period on ethylene production, fruit firmness and quality of ‘Cripps Pink’ apple were investigated. Fruit were harvested from Perth Hills and Donnybrook (Western Australia) at commercial maturity (CM), 2, 4 and 6 weeks after CM prior to 0, 45, 90 and 135 days cold storage in 2003 and 2004. Delayed harvest significantly increased ethylene production, CIE values a* and C* at both locations in 2 years. Delayed harvest and extended cold storage period increased the internal ethylene production and reduced fruit firmness, soluble solids concentration: titratable acidity (SSC:TA) ratio and reduced CIE values L*, b*, h° during both years and locations. Fruit harvested 2 weeks after CM can be cold‐stored for 90 days with acceptable fruit quality. If the fruit is intended to be sold fresh immediately in local markets, the harvest can be delayed up to 6 weeks after CM to harness substantially improved fruit colour with acceptable fruit quality.     

Effect of hot air treatment on quality and ripening of Chinese bayberry fruit

BACKGROUND: Postharvest decay and softening are the major factors limiting the extension of storage life of Chinese bayberry fruit. To evaluate the effects of hot air treatment (HAT) on Chinese bayberry fruit, fruits were stored at 2 °C after exposure to 20 °C (control), 40 °C (HAT₄₀), 45 °C (HAT₄₅) or 50 °C (HAT₅₀) hot air for 3 h. The effects of HAT on firmness, disease incidence, soluble solid content (SSC), titratable acidity (TA), respiration, ethylene production, pectic substances and activities of pectinmethylesterase (PME) and polygalacturonase (PG) were examined. RESULTS: HAT inhibited decrease in firmness, SSC and TA and retarded increase in disease incidence, while it promoted decrease in respiration rate and ethylene production. HAT suppressed the activities of PME and PG, which resulted in delaying the depolymerisation of chelator‐soluble and alkali‐soluble pectic substances and reducing the increase in water‐soluble pectic substances compared with control fruits. CONCLUSION: The present findings show that HAT can maintain postharvest quality and delay ripening of Chinese bayberry fruit and suggest that HAT could be considered for commercial use to extend the postharvest life of Chinese bayberry fruit. Copyright © 2008 Society of Chemical Industry