延迟和缩短苹果气调处理时间对贮藏效果的影响

 以新红星苹果为试材探讨延迟和缩短低氧气调新组合(10 ℃, 2 %O₂ + 7. 5 %CO₂) 处理时间对其贮藏效果的影响。结果表明, 贮藏123 d 时, 冷藏对照(0 ℃, 空气) 和常规气调处理(0 ℃, 3 %O₂ + 3 %CO₂) 果实的虎皮病果率分别为25. 6 %和1. 02 % , 果肉硬度分别为5. 79 和6. 52 kg/ cm², 而低氧新组合处理无虎皮病, 果肉硬度(6. 63 kg/ cm²) 显著高于冷藏对照, 而与常规气调处理无显著差异。10 ℃空气中放15 d 后再用低氧新组合处理108 d 的果实虎皮病果率6. 67 % , 果肉硬度(4. 8 kg/ cm²) 显著低于冷藏对照和常规气调处理。这些结果说明果实采后及时进行低氧气调处理是必要的。冷藏对照、常规气调处理和在10 ℃下低氧新组合处理123 d 的果实再于0 ℃空气中放58 d , 其虎皮病果率分别为46. 9 %、36. 4 %和0 , 果肉硬度分别为5. 28 、5. 21 和4. 5 kg/ cm²。在10 ℃下低氧新组合处理96 d 再冷藏的苹果, 在贮后50 d 时无虎皮病果, 果肉硬度为4. 67 kg/ cm² 。综合来看, 计划贮期约5 个月时, 10 ℃下低氧新组合处理的时间可由4 个月缩短为3. 3 个月。低氧气调新组合处理的苹果在气调期间α2法尼烯和共轭三烯的形成受到显著抑制。     

Control of superficial scald in ‘Granny Smith’ apples by ultra-low and stress levels of oxygen as an alternative to diphenylamine

Summary

‘Granny Smith’ apples were harvested at weekly intervals, commencing approximately 155 d after full bloom (DFFB), over two successive seasons. Subsamples of the fruit were stored for periods of five and six months, without the application of diphenylamine, under regular atmosphere (RA) (1990/91 season only), and ultra-low oxygen (ULO) controlled atmosphere (CA) conditions. Further samples were subjected to initial low oxygen stress (ILOS) conditions before ULO CA storage. During the 1989/90 season, scald development after five months’ storage was low for fruit which had been picked in the pre- and post-maturity phases, but high on fruit picked at optimum maturity (170 DFFB). Although storage regime had little effect on scald development after five months’ storage, the ILOS + ULO CA treatment resulted in lower levels of scald on the post-mature fruit after six months of storage than was the case under ULO CA storage alone. There was more scald in the 1990/91 season than in the previous season. Under RA storage conditions, scald levels were high after both five and six months of storage, and decreased only slightly the later the apples were picked. Relative to RA, storage under ULC CA conditions led to markedly lower scald levels on the post-mature fruit, but did not greatly reduce scald on the pre-mature and mature fruit. Storage under the ILOS + ULO CA regime, however, conferred low levels of superficial scald on pre-mature, mature and post-mature fruit after both five and six months of storage. These results suggest that although superficial scald on ‘Granny Smith’ apples can be inhibited by a combination of ILOS and ULO CA storage, the development of scald is also affected by factors other than maturity and storage period.     

Changes in Ripening Behaviors of 1-MCP-Treated ‘d’Anjou' Pears After Storage

Abstract

1-Methylcyclopropene (1-MCP), an ethylene action inhibitor, was applied to ‘d’Anjou' pears (Pyrus communis L.) at 20°C between 2 and 5 days after harvest. Scald of ‘d’Anjou' pears was completely controlled by 1-MCP at a concentration between 0.05 and 0.3 µl l1 after a prolonged cold storage plus 7 days of exposure to an environment with or without 500 µl l1 ethylene at a temperature of 20°C or 25°C. 1-MCP inhibited the biosyntheses of α-farnesene and its oxidative products (conjugated trienes) and thus controlled scald. However, fruit treated with the above concentrations of 1-MCP did not ripen normally in an environment with or without ethylene. Ethylene production and fruit softening of 1-MCP-treated ‘d’Anjou' pears were inhibited during 7 and 15 days at 20°C. ‘d’Anjou' fruit treated with 0.01 and 0.02 µl l¹ 1-MCP ripened normally on day 7 at 20°C after 3 months of cold storage at ? 1°C, and ripened fruit did not develop any incidence of scald. Untreated fruit developed substantial scald. After 4 months of storage or longer, both untreated fruit and fruit treated with 0.01 and 0.02 µl l 1 1-MCP developed an unacceptable incidence of scald upon ripening. Thus, use of other scald control methods may be necessary in addition to treatment with a low dosage of 1-MCP to insure both normal ripening and scald control for d'Anjou pear fruit from the Mid-Columbia district.     

1-MCP verlängert die Lagerfähigkeit und vermindert Schalenbräune bei der Apfelsorte ‘Berlepsch’

‘Berlepsch’ as an apple cultivar of large vitamin C contents in excess of 30?mg vitamin C/100?g FM looses marketing share due to its poor storage quality and sensitivity to superficial scald. The objective of the present work was to use 0, 500 or 1000?ppb of 1-MCP (Smartfresh^TM) for 24 hours at 2?°C to overcome these two cultivar-related shortcomings. Slightly overripe apples were stored at 2?°C, 95% relative humidity either in normal air (NA) or in controlled atmosphere (CA) under 2% CO₂ and 1.8% O₂. Each of these six treatments consisted of four replicates of ca. 20?kg apples each. Treatments with 1-MCP did not affect the fruit sugar content. While the storage conditions (NA or CA) did not affect initial fruit respiration, 1-MCP reduced final fruit respiration to ca. 60% and 1-MCP effects on respiration rates in shelf life were more pronounced than in storage. While 1-MCP reduced the initial ethylene formation from 70 to nearly 0?μl/kg/h, this effect was declined with prolonged storage. Similarly, the temperature driven increase in ethylene evolution during shelf life was not affected by 1-MCP treatments. MCP treated fruit lost less weight in storage and shelf life relative to untreated fruits. Doubling the 1-MCP concentration from 500?ppb to 1,000?ppb did not further reduce respiration, ethylene formation, loss of fresh mass or incidence of superficial scald. This corresponds to the dose of 1-MCP commonly used in fruit storage.     

低温对苹果贮藏过程中H_2O_2水平的影响

在低温贮藏条件下,苹果虎皮病从11一12月间开始发生并迅速加重.在此之前,果皮中H_2O_2水平逐渐上升,11—12月达最大值.H_2O_2水平的变化与细胞中保护系统和木质素合成有关.与晚采果相比,早采果中SOD和CAT活性均高,低温下CAT活性较SOD下降为快,早采果尤为显著,因此果皮中H_2O_2水平也高.抗氧化剂二苯胺对SOD和CAT无影响,但显著抑制木质素合成,降低H_2O_2水平,减少发病率.     

虎皮病的防治研究概况

虎皮病的防治主要包括化学和非化学防治。化学防治的方法很多，目前最有效的是使用二苯胺，但是人类出于对自身健康的考虑，许多消费者已开始不愿接受化学处理的果实，非化学防治成为人们研究的热点。非化学防治主要包括气调贮藏、采后热处理和虎皮病预测。     

Studies of the Physiologically-Active Volatile Organic Compounds Produced by Fruits : II. The Rate of Production of Carbon Dioxide and of Volatile Organic Compounds by King Edward VII Apples in Gas Storage,and the Effect of Removal of the Volatiles From the Atmosphere of the Store on the Incidence of Superficial Scald

The present method of controlling superficial scald of apples in gas storage by wrapping them in paper containing oil is usually very effective but is costly. This is mainly because it requires so much labour. It also takes time and delays the closing of the store. Can simpler, equally effective methods be found ? It was expected that removal of part of the volatile vapours given off by the apples, by circulating the storage atmosphere through a gas-mask type of filter, would reduce scald. This expectation was based on the theory that scald is caused by the accumulation of one or more of these volatiles in the storage atmosphere. Suitable filters were developed and experiments in which the storage atmosphere was analysed showed that these filters did remove a very large part of the apple volatiles. Nevertheless, it was found that the amount of scald occurring on unwrapped King Edward VII apples in gas storage was almost the same in a store with filters as in one without.

The well-known effect of gas storage in lowering the rate at which apples lose CO₂ is shown in the present paper by means of diagrams. It is this condition which is responsible for the extension of storage life of apples in gas mixtures.     

苹果低氧气调新组合贮后效应的利用研究

利用0.12mm聚乙烯薄膜大帐进行低氧气调新组合的较大规模应用试验,对2394kg玫瑰红苹果进行低氧处理,帐内O2浓度可下调至约2%,CO2浓度可自动维持在5%～8%的较理想状态,处理结束后很易转为MA自发气调。低氧处理后再MA贮藏的苹果,虎皮病果率低、症状轻,腐烂果少,果柄和果皮新鲜,叶绿素保持效果好,果肉硬度明显高于小包装气调和冷藏对照。说明利用塑膜大帐进行前期低氧新组合处理与后期自发气调、实现低氧气调新组合贮后效应的利用是可行的。     

Chlorophyll fluorescence as affected by some superficial defects in stored apples

Summary

Chlorophyll fluorescence, skin coloration and surface contour were measured for apple (Malus domestica Borkh.) fruit with and without common storage and handling surface defects. Defects included C0₂ injury in ‘Empire’, bitter pit in ‘Jonagold’, superficial scald in ‘Cortland’, ‘Law Rome’, ‘Gala’ and ‘Red Delicious’ and bruising in ‘Cortland’. Measurements were made along a transect established on the fruit surface. The fluorescence parameters, minimal fluorescence (Fo), maximal fluorescence (Fm) and photochemical efficiency (Fv/Fm, where Fv = Fm - Fo) were relatively similar around the circumference of undamaged control fruit. Skin colour was not found to influence chlorophyll fluorescence. With the exception of bruises, there were marked changes in fluorescence in the areas where surface disorders or damage had developed. C02 injury and bitter pit reduced Fv/Fm, whereas superficial scald did not. However, scald symptoms were accompanied by a reduction in Fo and Fm. The reduction in Fo and Fm became more marked as scald symptoms intensified during post-storage holding at 22°C. Chlorophyll fluorescence may have some potential for sorting fruit having superficial defects.     

Re-initiating softening ability of 1-methylcyclopropene-treated ‘Bartlett’ and ‘d’Anjou’ pears after regular air or controlled atmosphere storage

Summary

‘Bartlett’ and ‘d’Anjou’ pears treated with 300 nl l^–1 1-methylcyclopropene (1-MCP) did not soften to eating quality within 7 d, a desirable ripening period. A pre-conditioning method was evaluated as a means to re-initiate the softening ability of pears prior to marketing. Fruit were treated with 1-MCP and stored at –1°C in regular air, or in a controlled atmosphere for 2 – 9 months. After storage, fruit were pre-conditioned with nine temperature (10°, 15° or 20°C) and time (5, 10 or 20 d) combinations. Pre-conditioned fruit were then assessed for ripening ability following storage for 14 d at 20°C. The ripening ability of 1-MCP-treated ‘Bartlett’ fruit recovered in response to many pre-conditioning combinations of 10° – 20°C for 10 – 20 d, as indicated by a decrease in flesh firmness to 27 N or lower. The requirements for pre-conditioning regimes are storage atmosphere- and time-dependent. For ‘d’Anjou’ pears, no pre-conditioning combination resulted in re-initiating the ripening of fruit treated with 300 nl l^–1 1-MCP. However, when the 1-MCP dose was 50 nl l^–1, ‘d’Anjou’ pears ripened over an extended shelf-period with a substantial decrease in superficial scald. The results indicate that treatment with 1-MCP at approx. 50 nl l^–1, combined with a pre-conditioning prior to marketing, is a potential means to control scald in ‘d’Anjou’ fruit. Re-initiation of ripening occurred concomitantly with a substantial increase in ethylene production. The control of superficial scald by 1-MCP in ‘d’Anjou’ pears was due to the inhibition of the biosynthesis of -farnesene and conjugated trienes.     

苹果采后热空气处理对表面伤口愈合的影响

 以‘嘎拉’和‘红富士’苹果为对象，研究热空气处理（38°C 4d）对苹果伤口愈合的影响。扫描电镜观察发现，38°C 4d热空气处理能使苹果表面的果蜡融化，从而封堵微小伤口，并使真菌菌丝体胶囊化而失活，阻止病原菌的入侵。与人工刺伤后立即接种病原菌相比较，苹果伤口在38°C或者20°C下处理 4d后再接种病原菌能显著提高伤口的抵抗能力，降低伤口处病害的发生和发展。与20°C处理相比，38°C热处理有利于‘红富士’苹果人工刺伤伤口的愈合，但是不利于‘嘎拉’的伤口愈合。     

Multiformulation dips for controlling storage disorders of apples and pears. III. Throughput limitations in dip application

Effectiveness of post-harvest diphenylamine (DPA) dip treatments for superficial scald (scald) control is dependent on application method, DPA formulation, dip age, quantity of fruit throughput and the inclusion of additives (calcium chloride and fungicides).With bin-immersion systems, throughput up to 100 × 18 kg cases per 561 of dip, caused no loss of DPA. However, with an Australian miscible oil formulation DPA (M.O. Aust.) containing additives there was increased scald and lenticel spot (spot) after 50-case throughput, and with a wettable powder formulation DPA (P) there was increased spot after 50-case throughput, but these limitations were not apparent with an American miscible oil formulation DPA (M.O. U.S.). Replacing lost dip-volume with normal strength DPA after 50-case throughput prevented the occurrence of these disorders with further throughput. Dips which had had prior throughput and were then aged for 1–2 weeks were effective provided they were agitated before use.With bin-flooding systems using DPA (M.O. Aust.) or DPA (P), effective scald control was limited to the case throughput which was treated in 40–75 min. Exceeding this limitation caused the DPA (M.O. Aust.) emulsion to break down due to mechanical agitation in pumping, and DPA (P) to form a surface scum of DPA ingredient in the return tank. The DPA (M.O. U.S.) formulation was stable and effective in this system for at least 100 min pumping.     

Energiebilanzen für Obstimporte: Äpfel aus Deutschland oder Übersee?

This work compares the primary energy requirement for apples marketed in Germany in April which were either home-grown in Germany or imported from overseas. The primary energy requirement was calculated for apples (cv. ‘Braeburn’ and ‘Golden Delicious’) picked during mid-October near Bonn, Germany, with subsequent 5-month on-site CA storage at ca. 1°C until mid-March. This was compared with energy requirements for apples of the same cultivar grown in a Southern hemisphere winter in Hawke’s Bay, New Zealand or Grabouw-Elgin, Western Cape, South Africa, picked in March, and with subsequent 28- or 14-day transport, respectively, on reefers to Antwerp for sale in April in Germany. The primary energy required for cultivating Braeburn apples in New Zealand (ca. 2.1 MJ/kg apple fruit) represented 38% of their overall primary energy requirement, compared with 2.8 MJ/kg fruit in Germany or South Africa, with smaller harvests of 40 t/ha cf. 90 t/ha in New Zealand. Braeburn and Golden Delicious apples grown and stored locally in Germany consumed nearly 6 MJ/kg fruit, which included ca. 0.8 MJ/kg for 5-month CA storage during the winter. This compared favourably with 7.2–7.5 MJ/kg for overseas shipment from New Zealand or South Africa, i.e. a 22–27% greater energy requirement for imported fruits. The CA storage of home-grown apples in Germany partially compensated for the energy required to import the fresh fruit from overseas. To compensate fully for imports from South Africa or New Zealand, home-grown apples had to be stored locally for ca. 9 or 18 months, respectively, i.e. in the latter case beyond the next harvest. The lower primary energy required for domestic apple fruit is discussed with respect to providing local employment, fruit orchards preserving the countryside, fruit quality, food safety and quality assurance schemes such as QS and EUREP-GAP, food security of local fruit, and networking favouring regional produce.     

Heat treatment and harvest date interact in their effect on superficial scald of ‘Granny Smith’ apple

A study was made of the effect of hot water dips (HWD) at temperatures of 42, 44, 46 and 48 °C (HWD 42 °C, HWD 44 °C, HWD 46 °C and HWD 48 °C, respectively) for 3 min on development of superficial scald and the concentration of α-farnesene and conjugated trienols (CT), CT₂₅₉, CT₂₆₉, CT₂₈₁, as well as OD₂₀₀ on Granny Smith apple fruits harvested on three dates and stored 125 days in air at 2 °C. HWD 48 °C efficiently decreased surface scald in the second and third harvest. α-Farnesene and CT were measured spectrophotometrically and by HPLC. No clear relationship of OD₂₀₀ and scald development was observed. Correlation of scald index and OD₂₀₀ at the end of storage was negative for the second harvest date. There was no significant correlation between the scald index and CT₂₅₉. Scald index was positively correlated with CT₂₆₉ after 80 days for the second and third harvest and at the end of storage for the second harvest. CT₂₈₁ was spectrophotometrically detectable only at the end of the storage, for the third harvest date, in control, HWD 42 °C, and HWD 44 °C. HWD 42 °C had significantly higher CT₂₈₁ compared to HWD 44 °C and control. HPLC analysis of control samples revealed presence of CT₂₈₁ in all three harvest dates, and presence of at least two components, as was the case of CT₂₅₉ and CT₂₆₉. The ratio of these two components was different for all three CT species. Fruit maturity was an important factor determining the response of fruit to heat and occurrence of superficial scald. The results indicate that a successful treatment using HWD to control superficial scald may be obtained after further research and that there are still some questions on the role of different CT's in scald biochemistry that should be addressed in future research.     

1-MCP对“藤牧1号”苹果贮藏品质的影响

为研究1-甲基环丙烯(1-MCP)对早熟苹果品种“藤牧1号”冷藏品质和冷藏后货架品质的影响,分别以0(对照)、500、1 000和1 500 nL/L的1-MCP处理“藤牧1号”苹果,对各处理苹果在0℃贮藏期间,以及在冷藏40和60 d后货架期间的品质进行了测定.结果表明:1-MCP抑制了“藤牧1号”苹果冷藏期间呼吸和乙烯释放速率;延缓了硬度和可滴定酸含量下降;延缓了苹果总酚含量、多酚氧化酶活性高峰的出现,抑制了丙二醛含量的升高;对可溶性固形物和维生素C含量影响不明显.此外,1-MCP还延迟了冷藏40和60 d后7d货架期间果实的硬度、可滴定酸含量的下降,明显提高了果实好果率.从整体看,1 500 nL/L的1-MCP维持“藤牧1号”苹果冷藏和货架期间品质的效果优于其它3个处理.     

The action of phorone and other compounds in controlling superficial scald of apples

A new inhibitor of superficial scald, phorone (2,6-dimethylhepta-2,5-dien-4-one) is reported. Phorone reduced scald on ‘Granny Smith’ apples when applied by injection or as a vapour. Phorone was found to limit the accumulation of α-farnesene during storage and the amounts of conjugated triene oxidation products derived from α-farnesene. Monoterpenes also reduced α-farnesene, oxidation products and scald, but these compounds were less effective than phorone. In contrast, diphenylamine had little effect on the amount of α-farnesene in the fruit but it prevented the autoxidation of α-farnesene and controlled scald.     

Antioxidant Bioactive Compounds and Spoilage Microorganisms of Wax Apple (Syzygium samarangense) during Room Temperature Storage

Postharvest deterioration of wax apple leads to unacceptable appearances, physical and quality losses that raise serious concerns commercially. Bioactive compounds of wax apple and spoilage microorganisms were studied at room temperature storage (23 ± 1 °C). Antioxidant activity and total phenolic content increased up to a maximum of 1.56 mg AAE/100 g and 88.37 mg GAE/100 g, while prolonged storage resulted in 70.0% and 33.6% loss, respectively. Further, 80% loss in vitamin C content was observed from an initial value of 21.63 mg AAE/100 g during storage. Bacterial isolates of Enterobacter sakazakii, Klebsiella pneumoniae, Klebsiella planticola, Pantoea agglomerans, Chromobacterium violaceum, and Streptomyces roseochromogenus with microbial load of 1.19 * 10⁸ CFU/g fresh weight, and fungal isolates of Penicillium purpurogenum, Mucor hiemalis, Aspergillus niger, Aspergillus fumigatus, and Candida tropicalis with a total load of 5.64 * 10⁷ CFU/g fresh weight were identified as spoilage organisms. Bacterial isolates of Klebsiella pneumoniae was the most prevalent at 47.78%, occurring 21 times, while Penicillium purpurogenum was the most prevalent fungi, occurring 5 times at 38.46%. Results have significant implications on measures to preserve quality of wax apples during storage by adoption of advanced postharvest handling and processing approaches.     

前期低氧处理对梨虎皮病的防控及乙烯释放的影响

以'鸭梨'为试材,空气处理为对照,分析比较前期超低氧胁迫(0.8％02+0.5％C02处理15 d,转入5.0％02+0.5％C02长期贮藏)、静态低氧气调(降温后直接转入5.0％02+0.5％C02)和"两阶段"缓慢降氧气调(10.0％02+0.5％C02处理15d,转入5.0％02+0.5％C02长期贮藏)对'鸭梨...     

Determination of the optimal pre-storage delayed cooling regime to control disorders and maintain quality in ‘Honeycrisp’TM apples

Summary

Several pre-storage time (0, 1, 2, 4, and 6 d) and temperature (3.5º, 10º, 15º, 20º, 25º, and 30ºC) delayed cooling (DC) treatments were tested on harvested ‘Honeycrisp’^TM apples to determine which combination was optimal for reducing soft scald and low temperature breakdown (LTB), while maintaining the highest fruit quality [i.e., firmness, minimal mass loss, titratable acidity (TA), soluble solids content (SSC), absence of rot, and minimal skin greasiness] after 4 months of refrigerated air (RA) storage. Fruit were harvested from three separate Annapolis Valley (Nova Scotia) orchard sites in 2006 and in 2007. Multiple linear regression and surface response curves showed that fruit firmness and SSC generally increased throughout the DC treatment, but were affected curvilinearly by temperature, reaching a maximum at approx. 15ºC, then declining. Loss of fruit mass was positively related to a (day temperature²) interaction, indicating that it increased synergistically the longer and the warmer the DC treatment. Fruit acidity was affected only by temperature, with the highest TA values at approx. 15ºC, then declining at higher DC temperatures. Multiple logistic regression and surface responses demonstrated that the incidence of soft scald declined curvilinearly the longer and the warmer the DC treatment, while LTB declined curvilinearly with increasing DC temperature only. A positive (day² temperature²) interaction indicated that fruit greasiness increased non-linearly as the duration and temperature of DC increased. Collectively, these results show that both soft scald and LTB were suppressed or eliminated by a DC regime of 25ºC for 1 – 2 d, or 30ºC for 1 d, without incurring a major reduction in fruit quality.