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1.
Chemical–physical properties, colour parameters, antioxidant activities (AA), carotenoid and polyphenol levels (CL) in seven cultivars of yellow flesh peaches, five cultivars of yellow flesh nectarines and one cultivar of white flesh nectarines at harvest time and after 7 days of cold storage were evaluated. Peaches had major variability in flesh firmness (FF) and titratable acidity (TA) and lower soluble solid concentration (SSC) than nectarines. Evaluation of ground colour parameters, a*, b* and L*, showed that nectarines had a yellow-orange hue with high lightness, while peaches were darker, tending to red-green. Hydrophilic, lipophilic antioxidant activities of extracts (W-AA and L-AA), carotenoids and polyphenols levels (CL and PL) were evaluated and their relation with commercial maturation. The average of W-AA at harvest time was 11.0 TEAC, while the L-AA values at harvest time was on average higher in peaches (2.0 TEAC) than in nectarines (1.3 TEAC). The yellow flesh had higher amounts of total carotenoids (182.45 μg/100 g fw for peaches and 117.37 μg/100 g fw for yellow flesh nectarines). During cold storage, W-AA increased for nectarines (+22.9% in yellow flesh and +19.2% in white flesh) and peaches as well as polyphenolic compounds (+13.37%) while, contents of carotenoids decreased (−8.7%).  相似文献   

2.
Plum (Prunus domestica L. cv. ‘President’) fruits were harvested at two pre-climacteric stages of ripeness (stage 1 and stage 2), and then treated with 1-methylcyclopropene (1-MCP) at two doses (0.3 and 0.5 μl l−1) followed by 1, 2, 3, 4 and 5 weeks of cold storage and their respective 7 days of shelf life at 20 °C. Both 1-MCP doses were effective in terms of ethylene inhibition during shelf life after cold storage, for both ripening stages. Similarly, lower weight losses, delayed colour changes, reduced softening rate and diminished ripening index were found in 1-MCP treated plums than in controls at both stages of ripeness. Hence, during cold storage and shelf life, the efficacy of 1-MCP on ethylene production, weight loss, pulp firmness and ripening index was dose-dependent, while for colour and respiration rate the dose-dependence was only found during shelf life. The storability of 1-MCP treated plums could be extended up to 4 weeks of cold storage plus 7 days at 20 °C, and only up to 1 week of cold storage plus 7 days at 20 °C for controls. Then, 1-MCP is an effective tool for quality improvement and extension of shelf life in plums, and fruit might be harvested in stage 2 of ripening, at which the most desirable organoleptic attributes had been developed on tree.  相似文献   

3.
European plum ( Prunus domestica L.) cv. 'Oullins Gage' was harvested according to firmness on five harvest dates. Fruit was analysed at harvest and during storage for weight loss, firmness, total soluble solids (TSS), titratable acidity (TA) and skin colour before and after a 3-day shelf-life period at 20 °C. Significant differences were found among harvest dates in fruit mass, skin colour, firmness, TSS and TA. Fruit mass, TSS and colour b * increased, whereas firmness and TA decreased significantly during the harvesting period. Firmness parameter as a maximum maturity index and TSS:TA (or b * colour, a non-destructive measurement) as a minimum maturity index could be used to distinguish maturity at harvest. It is suggested that the best post-storage quality of 'Oullins Gage' plums would be obtained when fruit is harvested with TSS:TA >9 or b * colour >30, but with a firmness >20N to assure a long storage life.  相似文献   

4.
While nitrogen (N) and potassium (K) fertilizers are commonly used in tomato fields for increasing plant growth and productivity, concepts regarding the interactive effects of these elements on tomato fruit quality during storage are ambiguous. The interactive effects of potassium (0, 250 and 500 mg kg soil??1) and nitrogen (0, 150 and 300 mg kg soil??1) fertilizers were tested on tomato fruit size at harvest, and their quality was evaluated after 30 days of storage at 4 °C. Fruit mass, firmness, taste-related parameters, inorganic nutrients, bioactive compounds, and antioxidative capacity of the fruits were investigated after the storage period. Application of 250–500 mg K in combination with 150 mg N per kg soil improved fruit mass at harvest and reduced loss of mass during storage. By increasing the soil’s K supply, the fruits exhibited significant increases in their amount of potassium, TSS and TA contents, antioxidative capacity, concentrations of lycopene, phenolics and ascorbic acid. Nonetheless, increasing the soil’s K concentration reduced Ca concentration and firmness of the fruits. By increasing the N concentration in the soil, a trend of decline was observed in the fruits’ TSS, soluble phenolics, lycopene and ascorbic acid contents. However, higher amounts of N and TA contents were detected in fruits treated with 300 mg N kg soil??1. N treatments did not affect the antioxidative capacity of the fruits. Accordingly, application of 250 mg K?+?150 mg N kg soil??1 was suggested as the optimum treatment that could yield tomato fruits with high quality and that would also have improved storage capability.  相似文献   

5.
为研究不同浓度硫化氢(Hydrogen sulfide,H2S)处理对采后粉蕉果实品质的影响,将粉蕉果实分别用0.3、0.6和0.9 mmol/L NaHS溶液释放的H2S处理,并定期观察和测定了贮藏期间果实的硬度、色泽、失重率、褐变指数、可溶性固形物(TSS)、可滴定酸(TA)、呼吸速率和乙烯生成速率。结果表明:H2S处理明显延缓了粉蕉果实表皮黄化和果肉褐变指数的增加,减缓了果实的软化和失重率的上升,果实TSS含量以及TA含量上升幅度受到一定程度抑制。并且,除了TSS 3个不同浓度处理组间差别不显著外(P>0.05),其余都表现出0.6 mmol/L NaHS处理组效果更明显;与此同时,经NaHS处理还显著地抑制了果实的呼吸作用和乙烯生成速率的上升(P<0.05),推迟了呼吸和乙烯达到峰值的时间4 d。但不同浓度NaHS处理组间对乙烯影响不显著(P>0.05)。综合来看,不同浓度NaHS处理均可以延缓采后粉蕉果实的成熟衰老,其中以0.6 mmol/L NaHS处理的保鲜效果最明显。  相似文献   

6.
The effects of 1-methylcyclopropene (1-MCP) on quality and cell wall hydrolases activities changes in fresh-cut muskmelon fruit stored at 4?±?1 °C for 7 days were investigated. The results showed that ethylene production of the fresh-cut fruit remained constant during refrigerated storage. 1-MCP treatments delayed the loss of fresh weight and the increase in electrolyte leakage and maintained the firmness of the fresh-cut fruit. The best results are showed in the fresh-cut fruit treated with 1.0 μL L?1 1-MCP. The use of 1-MCP had no influence on the total soluble solids (TSS) content and pH of the fresh-cut fruit which they remained constant over storage. The titratable acidity (TA) of the fresh-cut fruit decreased during storage and the sample treated with 1.0 μL L?1 1-MCP showed the lowest data. TSS/TA ratio increased during storage and the TSS/TA ratio was lower in 1-MCP-treated samples than that for the control one. The use of 1-MCP inhibited polygalacturonase (PG), β-galactosidase (β-Gal) and β-galactanase activities, whereas the increases in these enzymes activities were found in the control. Antioxidant capacity and total phenolics content of both 1-MCP-treated and untreated samples remained constant over storage. The reduction of total ascorbic acid content was detected after 7 days of storage. The ascorbic acid content in 1-MCP-treated sample was slightly higher, although not significantly different, than that of the control after 7 days. These results suggest that the loss of firmness was the key factor affecting quality of fresh-cut muskmelon fruit and the use of 1-MCP maintained the quality and inhibited the loss of firmness by retarding the increase in electrolyte leakage and inhibiting cell wall hydrolases activities.  相似文献   

7.
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.  相似文献   

8.
Storage at 2% O2 plus 5% CO2 at 1.1°C maintained higher flesh firmness and lower pH and retarded decay more effectively than air storage of immature (M1) and over-mature (M3) Patterson and Tilton apricot fruits. CA storage of fruits picked at the optimum maturity stage (M2) produced little benefit over air storage, however. -Treatment with 100 ppm ethylene for 48 hours accelerated softening and color change at 20°C compared to ripening in air and may potentially be used to prepare immature apricot fruits for canning in the shortest possible time. Large differences in storageability and canned quality following storage were found among the five clingstone peach cultivars tested. Loadel and Carolyn: peaches, if in sound condition at harvest, can be stored for up to 4 wk under 2% O2+ 5% CO2 at 1.1°C. Andross, Klamt and Halford peaches should be stored for shorter storage periods only. Fruits ripened at 20°C with ethylene (100 ppm for 48 hr) were similar to those ripened without it in appearance, texture, and flavor.  相似文献   

9.
Peach is characterised by a rapid senescence associated with a high production of autocatalytic ethylene at the beginning of ripening, a fact which reduces markedly its postharvest shelf-life. The application of antisenescent compounds after harvesting has been assayed to solve this problem. One of the newest and more promising compounds is the free radical gas nitric oxide (NO). In this work, peaches of cv. ‘Rojo Rito’ were treated with 5 μL L−1 of NO for 4 h, at 20 °C, and then stored at the same temperature for 14 days. Untreated fruits stored under the same conditions were used as control fruits in the experiment. Key physiological parameters of senescence (ethylene production and respiratory rate) and quality parameters (firmness, titrable acidity, total soluble solids and colour) were analysed. A particular emphasis was placed on the analysis of the oxidative status and the antioxidant capacity during storage and as a response to the NO treatment. The ethylene production and respiratory rate of fruits treated with NO were lower than those of control fruits. Treated fruits underwent a lesser loss of firmness during storage. The degree of disintegration of cell membranes, assessed as the percentage of electrolyte leakage, was also lower in fruits treated with NO. NO did not seem to affect lipid peroxidation or LOX activity, but it did affect PPO activity. The treatment with NO stimulated POX activity and, especially, SOD and CAT activities. It seems that total carotenoids and free ASC were not influenced by the pretreatment; however, the oxidised form of ASC, DHA, showed a slight increase. NO seemed to have a beneficial effect on the oxidation equilibrium and the antioxidant capacity of peach fruit. A delay in the initiation of the senescence of fruits treated with NO, that extended the postharvest shelf-life, was observed.  相似文献   

10.
BACKGROUND: Plum has a very short storage life. The role of pre‐ or post‐harvest applications of putrescine (PUT) and low temperature storage on fruit ripening and quality was investigated in plum fruit (Prunus salicina Lindl. cv. Angelino). RESULTS: Pre‐ or post‐harvest PUT treatments [(0.1, 1.0 or 2.0 mmol L?1) + 0.01% Tween‐20 as a surfactant] delayed and suppressed the climacteric ethylene production and respiration rate irrespective of the method used to apply PUT. PUT‐treated fruit following low temperature storage (0 ± 1 °C; 90 ± 5% RH), at the ripe stage exhibited higher fruit firmness and titratable acidity (TA), while soluble solids content (SSC), levels of ascorbic acid, total carotenoids and total antioxidants were lower than in untreated fruit. Fruit both sprayed with PUT and stored in low temperature for 6 weeks, at the ripe stage showed reduced respiration rate, delayed changes in the SSC:TA ratio and levels of total carotenoids compared to post‐harvest PUT application. CONCLUSION: Pre‐harvest application of 2.0 mmol L?1 PUT 1 week before the anticipated commercial harvest was more effective in delaying plum fruit ripening and can be used to extend the storage (0 ± 1 °C) life of plums for up to 6 weeks with minimum losses in fruit quality. Copyright © 2008 Society of Chemical Industry  相似文献   

11.
Preconditioning is a thermal treatment that consists in maintaining stone fruits immediately after harvest and prior to cold storage at 20 °C for 24–48 h in special chambers aimed to extend fruit market life reducing chilling injury symptoms. This work investigates whether preconditioned ‘September Sun’ peaches had better eating quality than control fruit. Commercially harvested peaches were preconditioned and transferred to cold storage for 12, 26 and 40 days and evaluated for sensory characteristic perception after a ripening period at 20 °C. Acceptability of preconditioned fruit was higher than control fruit during this 40‐day cold‐storage period. Preconditioned and control fruit were also segregated into two clusters by PCA analysis; preconditioned fruit clustered together and show association to acceptability, sweetness and juiciness, while the second cluster was associated with flesh texture, acidity and aroma, suggesting the positive effect of preconditioning on final fruit quality. Preconditioned fruit maintained their sensory characteristics longer than control fruit during this 40‐day cold‐storage period.  相似文献   

12.
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  相似文献   

13.
Antisense ACC‐oxidase Cantaloupe Charentais melons, unsuitable for autocatalytic ethylene production, were harvested at different ages and exposed to a standard post‐harvest manipulation to reproduce the handling chain that occurs from harvesting to retail sale. The stages were as follows: storage in a chamber at 2 °C during 2 or 3 weeks, second storage at 8 °C for 4 days, treatment with 50 ppm ethylene for 2 days and, finally, maintenance at 20 °C for four more days. The date of harvest and the different periods of storage at 2 °C assayed did not affect the final de‐greening of the rind, while the change in pulp colour depended on the harvest date. Storage conditions also influenced the texture of the pulp and acidity. Weight loss was dependent mainly on date of harvest, like soluble solids content, although the period of storage at 2 °C influenced too. The impact of cold on the appearance of the fruits is discussed. Copyright © 2007 Society of Chemical Industry  相似文献   

14.
The effects of cold storage and shelf life of ‘Big Top,’ ‘Honey Blazecov,’ ‘Honey Royalecov,’ ‘Venus,’ ‘August Red,’ and ‘Nectagalacov’ nectarines were evaluated. Volatile compounds, firmness, soluble solids content, titratable acidity, color, and degree of consumer acceptance of the fruit were determined at harvest, after storage at ?0.5 °C for 10, 20, or 40 days and following 3 days at 20 °C. Ten days cold storage plus 3 days at 20 °C produced the highest total ester emission for ‘Nectagalacov’ and ‘August Red,’ while similar results were obtained after 10 days cold storage for the ‘Big Top’ and ‘Honey Blazecov’ and 20 days cold storage for ‘Honey Royalecov’ and ‘Venus.’ For ‘Nectagalacov,’ this higher total ester emission coincided with the greatest percentage of satisfied consumers. Increased consumer acceptance was associated with the cultivars and storage time that resulted in firmer fruits and greater concentrations of specific volatile compounds.  相似文献   

15.
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  相似文献   

16.
Treatment of mango (Mangifera indica cv ‘Kent’) fruits with methyl jasmonate (MJ) vapour for 20 h at 20 °C reduced chilling injury (CI) symptoms and enhanced skin colour development. MJ at 10?4 M was the most effective concentration for reducing CI and decay in fruits stored at 5 °C followed by 7 days at 20 °C (shelf‐life period). The use of 10?5 M MJ enhanced yellow and red colour development of mangoes stored at 20 °C. These fruits possessed higher L*, a* and b* values than untreated fruits and those treated with 10?4 M MJ. Ripening processes were inhibited by cold storage (5 °C) in control fruits. After cold storage and shelf‐life period, fruits treated with 10?5 M MJ ripened normally and contained the highest total soluble solids (TSS). These fruits also maintained higher sugar and organic acid levels than fruits subjected to other treatments. We concluded that MJ treatment could be used to reduce decay and CI symptoms and also to improve colour development of mango fruits without adversely affecting quality. © 2001 Society of Chemical Industry  相似文献   

17.
BACKGROUND: In Florida, tomatoes are harvested green (GR), which includes mature green (MG) and immature green (IG) fruits, and stored at low temperature (13 °C), resulting in poor flavour. Flavour improvement might be achieved if fruits were harvested with some colour (to eliminate IG fruits) and/or stored at higher temperature with the ripening inhibitor 1‐methylcyclopropene (1‐MCP). RESULTS: ‘Florida 47’ tomatoes were harvested at GR (MG + IG), breaker (BR), turning (TR) and pink (PK) stages, treated (+) or not (?) with 1‐MCP and stored at 13 and/or 18 °C. 1‐MCP treatment resulted in a gain of up to 6 days of shelf life depending on harvest maturity and storage temperature. Storage at 18 °C rather than 13 °C resulted in an increase in internal red colour, soluble solids (SS)/titratable acidity (TA) ratio and levels of many volatiles studied. The shelf life of BR (+) MCP fruits stored at 13 °C was similar to that of MG fruits. IG fruits exhibited lowest levels of SS, TA and ten volatiles compared with BR fruits. CONCLUSION: Harvesting tomatoes with colour (BR), thereby eliminating IG fruits, and treating with 1‐MCP resulted in better quality with adequate shelf life. Published 2011 by John Wiley & Sons, Ltd.  相似文献   

18.
贮前热处理对番茄采后生理的影响   总被引:8,自引:1,他引:8  
肖红梅  周光宏 《食品科学》2004,25(8):184-187
绿熟番茄采后用38℃热水处理60min,晾干,1±1℃,RH80%~95%冷藏37d后,转入20℃后熟,以20℃室温水处理为对照。结果显示,热处理果实的后熟率比对照提高了1.8倍。贮前热水处理对冷藏中果实的硬度和多聚半乳糖醛酸酶(PG)活性无显著影响,但促进该酶在后熟期间的增加,却减缓果实的软化;热处理刺激果实的呼吸、1-氨基环丙烷-1-羧酸(ACC)含量的增加,和ACC合酶(ACS)活性、乙烯含量的减少,但长期冷藏后作用消失,且显著增加后熟期间ACS的活性、ACC含量、乙烯生成以及呼吸强度。热处理可能通过调节乙烯的代谢来促进果实的后熟,降低果实的冷害。  相似文献   

19.
研究了60%和80%2种采收成熟度对不同后熟条件下(自然成熟、促进成熟和抑制成熟)台农芒果贮藏品质的影响。结果表明:与对照(自然成熟)相比,使用乙烯利处理台农芒果果实,加速了2种成熟度果实的成熟进程,而使用热处理结合乙烯吸收剂处理则具有明显的延缓病害发生和果实软化,抑制可溶性糖积累、有机酸和Vc降解的作用。在同一种后熟条件下(自然成熟、促进成熟和抑制成熟的任何一种),60%成熟度的果实其品质变化慢于80%成熟度的果实,但其风味品质却差于80%成熟度的果实。  相似文献   

20.
BACKGROUND: A series of physico‐chemical quality (peel and pulp colours, pulp firmness, fruit pH, sugars and acids content, respiration rate and ethylene production) were conducted to study the optimum harvest periods (either week 11 or week 12 after emergence of the first hand) of Rastali banana (Musa AAB Rastali) based on the fruit quality during ripening. RESULT: Rastali banana fruit exhibited a climacteric rise with the peaks of both CO2 and ethylene production occurring simultaneously at day 3 after ripening was initiated and declined at day 5 when fruits entered the senescence stage. De‐greening was observed in both of the harvesting weeks with peel turned from green to yellow, tissue softening, and fruits became more acidic and sweeter as ripening progressed. Sucrose, fructose and glucose were the main sugars found while malic, citric and succinic acids were the main organic acids found in the fruit. CONCLUSION: Rastali banana harvested at weeks 11 and 12 can be considered as commercial harvest period when the fruits have developed good organoleptic and quality attributes during ripening. However, Rastali banana fruit at more mature stage of harvest maturity taste slightly sweeter and softer with higher ethylene production which also means the fruits may undergo senescence faster than fruit harvested at week 11. Copyright © 2011 Society of Chemical Industry  相似文献   

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