Incidence Of Internal Browning Research Articles

Postharvest physiology, storage quality and physiological disorders of ‘Gem’ pear (Pyrus communis L.) treated with 1-methylcyclopropene

‘Gem’ is a crisp, juicy European pear (Pyrus communis L.) that can be consumed immediately at harvest or directly from cold storage. Alternatively, ‘Gem’ pears can ripen (5 d of 20 °C) to a soft, buttery, juicy texture once fruit accumulate 30 to 60 d of low temperature chill. In either condition, ‘Gem’ has a relatively short postharvest storage life of 5 months in regular air (RA). The purpose of this work was to evaluate two concentrations of 1-methylcyclopropene (1-MCP), 0.15 and 0.3 μL L−1, to maintain crisp, juicy textural properties and extend the postharvest storage life of ‘Gem’. Fruit were treated with 1-MCP, held in −1.1 °C RA and evaluated monthly (+1 d at 20 °C) for 7 months. Only minor differences were observed between 0.15 and 0.3 μL L−1 1-MCP for any of the response factors assessed. The respiration (Rs) and ethylene production rates of non-treated fruit increased ∼2- and 30-fold, respectively, between 2 and 7 months. Fruit firmness (FF), peel chlorophyll content (IAD), and titratable acidity (TA) all decreased linearly over the 7-month storage period. Treatment with 1-MCP completely inhibited internal ethylene production for the first four months. Ethylene production increased linearly between 5 and 7 months to a maximum value ∼15% of non-treated fruit. 1-MCP similarly suppressed Rs. FF, IAD, and TA were all significantly higher for 1-MCP-treated fruit than non-treated fruit. 1-MCP maintained the crisp and juicy textural properties of non-ripened fruit throughout the entire 7-month experiment by inhibiting ripening, despite a five-day 20 °C ripening treatment. In contrast, non-treated ‘Gem’ ripened after 2 months; however, the eating quality of non-treated fruit decreased after 5 months. Poor eating quality was associated with mealiness and insufficient softening after ripening. Internal browning and scald were first observed in non-treated fruit following five months of RA and reached levels of 26% and 85%, respectively, after seven months. The development of scald was closely associated with the accumulation of α-farnesene and conjugated trienols (CTols) in the fruit skin. 1-MCP significantly reduced the incidence of internal browning and completely inhibited the development of scald. Overall, 0.15 μL L−1 1-MCP maintained texture and fruit quality for 7 months RA and reduced the incidence of physiological disorders.

Application of pre- and postharvest salicylic acid on internal browning alleviation and postharvest quality of ‘Phulae’ pineapple fruit

The effect of pre- and postharvest salicylic acid (SA) treatments on internal browning (IB) alleviation and postharvest quality of pineapple (Ananas comosus L. 'Phulae') fruit were investigated. The experiment was divided into 4 treatments: preharvest SA (Pre SA), postharvest SA (Post SA), pre- and postharvest SA (Pre SA + Post SA) and non-treated was as a control. After treatment fruit was stored at 10°C for up to 28 days. Quality parameters including IB incidence, peel and flesh color, weight loss, total soluble solid (TSS), titratable acidity (TA), TSS/TA ratio, ascorbic acid (AA), total phenolics (TP), antioxidant activities by ferric reducing antioxidant power (FRAP) assays and the product of lipid peroxidation by measuring of malondialdehyde (MDA) contents, were analyzed every 7 days. The results showed that post-SA was the most effective treatment on reducing IB. The IB incidence of all treatments became more severe when moved and held to 25°C. However, SA did not affect fruit color, TSS, TSS/TA ratio and ascorbic acid content while TA and weight loss increased with storage time. For TA, at the end of storage, control treatment was significantly higher than the other treatments. The TP content of all treatments trended to increase during storage while FRAP activity trended to decrease on day 7 subsequently increase until end of storage. SA treatments could maintain higher FRAP activity than the control during storage. In addition, MDA content and PPO, POD, PAL activity were lower in SA treatments when compared with control. SA application alleviated IB in 'Phulae' pineapple which may involve reduction of lipid oxidation and maintaining of antioxidant activity in fruit including enzyme activities.

Calcium chloride and calcium gluconate peduncle infiltrations alleviate the internal browning of Queen pineapple in refrigerated storage

This study determined the effects of calcium chloride (CaCl2) and calcium gluconate (CaGlu) in alleviating the incidence of internal browning (IB) in ‘Queen’ pineapple (Ananas comosus) cv. ‘Sawi’ during storage at 13 °C. Pineapples were vertically peduncle-infiltrated with 2% CaCl2 or 2% CaGlu for 48 h. IB and browning-related factors of tissue adjacent to the core were investigated after 7 and 14 days of cold storage followed by 2 days at room temperature. CaGlu treatment alleviated IB intensity and severity more effectively than CaCl2. CaCl2 and CaGlu retarded membrane peroxidation and the activity of browning enzymes such as phenylalanine ammonia-lyase and polyphenol oxidase and increased the total phenols in the fruit. However, CaGlu-treated fruit had lower levels of tissue electrolyte leakage and lipoxygenase activity and higher antioxidant capacity and antioxidant enzyme activity. This evidence suggests that CaGlu peduncle infiltration is the preferred choice for alleviating IB in ‘Queen’ pineapple during low temperature storage.

QUALITY PRESERVATION OF ‘LAETITIA’ PLUMS IN ACTIVE MODIFIED ATMOSPHERE STORAGE

ABSTRACT Recent studies have shown that passive modified atmosphere storage (MA) delays the ripening of ‘Laetitia’ plums but it increases the incidence of internal browning in comparison to cold storage (CS), possibly due to high CO2 and/or ethylene accumulation inside the package. The aim of this study was to evaluate the effect of active MA conditions [LDPE film (40 µm)] with CO2 absorber combined with low ethylene (LE) on ripening and quality preservation of ‘Laetitia’ plums during storage at 0.5ºC±0.1ºC and RH of 96%±2%. The treatments evaluated were cold storage (CS; 21.0 kPa O2 + <0.03 kPa CO2); nonperforated MA with CO2 absorber; non-perforated MA with CO2 absorber and LE; perforated MA (with two perforations with diameter = 0.5 mm) with CO2 absorber; and perforated MA with CO2 absorber and LE. The partial pressures of O2 + CO2 (kPa) were 1.2 + <0.1 and 2.8 + <0.1, in non-perforated and perforated MA, respectively. Active MA, mainly non-perforated package, with CO2 absorber and LE, delayed fruit ripening, but did not reduce the incidence of internal breakdown in ‘Laetitia’ plums cold stored for 60 days. Fruits in active MA, with perforated or non-perforated package, with CO2 absorber and LE, showed lower intensity of internal breakdown than CS.

Internal browning disorder of eight pear cultivars affected by bioactive constituents and enzyme activity

Internal browning (IB) is a disorder in pears that is frequently observed in some cultivars. The present research was carried out to study biochemical changes and IB disorder of pear fruit during storage and ripening. Eight pear cultivars harvested and stored at 1°C up to 90days. IB incidence, some bioactive compounds, polyphenol oxidase (PPO), peroxidase (POX), and superoxide dismutase (SOD) enzymes activities were measured during storage. IB increased during storage time but the susceptibility of cultivars was different. The ascorbic acid (AA), antioxidant capacity (AC) and SOD activity decreased while POX activity increased during storage but the rate of changes were different in studied cultivars. Total phenol (TP) and total flavonoid (TF) average content varied among pear cultivars and the highest TP and TF were observed in ‘Bakhi’ cultivars during storage. Fruit IB had positive correlation with the PPO activity, but negative correlation with TP, AC and AA.

POTENCIAIS BENEFÍCIOS DO AUMENTO DA TEMPERATURA DE ARMAZENAGEM EM ATMOSFERA CONTROLADA DE MAÇÃS ‘GALA’ TRATADAS COM 1-MCP

RESUMO O armazenamento refrigerado pode induzir o desenvolvimento de danos por frio (caracterizado pelo escurecimento de polpa) em maçãs de algumas cultivares, mesmo quando mantidas em temperatura superior ao ponto de congelamento. O presente estudo avaliou o aumento da temperatura de armazenagem de maçãs clones de ‘Gala’ sob atmosfera controlada (AC), tratadas com 1-metilciclopropeno (1-MCP), como método para redução do desenvolvimento de escurecimento da polpa e do consumo de energia durante o armazenamento. Experimentos foram conduzidos em 2011, com maçãs produzidas em Fraiburgo (armazenadas em câmaras experimentais a -0,3 e 1,2 °C, e em câmaras comerciais a 0,7 e 2 °C) e em São Joaquim (armazenadas em câmaras comerciais a 0,8; 1,4 e 1,9 °C). Frutos de todos os tratamentos foram mantidos sob AC (1,8±0,2 kPa de O2 e 2,0±0,2 kPa de CO2/UR de 91±4%), sendo que metade dos frutos de cada temperatura de armazenamento foi tratada com 1-MCP. Os frutos foram analisados após o armazenamento em AC quanto à firmeza da polpa e incidência de escurecimento da polpa, rachaduras e podridões. De maneira geral, maçãs armazenadas em temperaturas mais elevadas mantiveram melhor firmeza da polpa e apresentaram menor incidência de escurecimento da polpa rachaduras e podridões, quando não tratadas com 1-MCP. O tratamento com 1-MCP retardou a perda de firmeza de polpa e reduziu a ocorrência de escurecimento de polpa e rachaduras. O aumento da temperatura de armazenagem em câmaras comerciais de AC em Fraiburgo, de 0,7 °C para 2,0 °C resultou em economia no consumo de energia em aproximadamente 21% para ventilação do ar da câmara e 50% para refrigeração.

Effect of harvesting date and packaging materials on core browning and phenolic contents of pear cv. Punjab Beauty during storage

Core browning in pears is characterized by softening and browning of tissues and development of cavities. It is one of the major disorders that develop during storage of pears. The relationship between core browning, total phenolic contents in relation to harvest time and packaging materials during storage was investigated in pear fruits cv. Punjab Beauty. Results indicated that core browning incidence was significantly higher in fruits from the last harvest. The fruits harvested 125 and 140 days after full bloom had 2.88 and 5.57 per cent core browning incidence, respectively after a storage period of 60 days, as compared to 13.30 per cent incidence in fruits harvested 155 days after full bloom. It is concluded that the lower incidence of internal browning in early harvested fruits was due to the presence of higher level of total phenolic contents than in late harvested fruits. Among the various packaging materials, CFB boxes proved to be the most effective in reducing the core browning in the fruits.

Effects of multiple 1-methylcyclopropene treatments on apple fruit quality and disorders in controlled atmosphere storage

The objective of this study was to investigate the effects of multiple 1-methylcyclopropene (1-MCP) treatments on fruit quality and disorder development in apples, with a second 1-MCP treatment applied after several months of controlled atmosphere (CA) storage. ‘McIntosh’, ‘Empire’, and ‘Northern Spy’ apples were harvested from commercial orchards and cooled overnight to 3°C. 1-MCP (1μLL−1) was applied 2d after harvest and then again to half of the fruit after 4 months of CA storage. ‘Northern Spy’ apples also received a single 1-MCP treatment after 4 months of CA storage. Similar fruit from all cultivars were also not treated with 1-MCP. ‘McIntosh’ and ‘Empire’ were held at 3°C and ‘Northern Spy’ at 0°C for 9 months in CA storage (2.5kPa O2+2kPa CO2 for ‘Empire’, 2.5kPa CO2 for ‘Northern Spy’, and 2.5 up to 4.5kPa CO2 for ‘McIntosh’). Overall, 1-MCP reduced internal ethylene production, and improved firmness and acidity retention in all apple cultivars. The addition of a second 1-MCP treatment after 4 months of CA storage further improved firmness retention in ‘McIntosh’ and late harvested ‘Empire’ apples after 7d at room temperature. ‘Northern Spy’ apples treated with 1-MCP had lower incidence of external CO2 injury, regardless of 1-MCP treatment timing. Multiple 1-MCP treatments had varying effects on the incidence of core browning; late-harvested ‘McIntosh’ treated twice with 1-MCP exhibited the highest incidence of core browning, while late-harvested ‘Empire’ treated twice had less core browning than those not treated. ‘Northern Spy’ treated only at harvest time had more core browning compared to those treated only or also after 4 months of CA storage and non-treated fruit. 1-MCP treatment had no significant effect on the incidence of internal browning in ‘McIntosh’ or ‘Empire’ apples. These results suggest that a second application of 1-MCP after 4 months of CA storage may improve firmness retention in some cultivars during holding at room temperature, but it can also have variable responses associated with susceptibility to disorders, especially when holding apples in long-term CA storage.

INTERNAL BROWNING IN 'KANZI®' APPLES - REASONS AND POSSIBILITIES TO REDUCE THE DISORDER

‘Kanzi’® (‘Nicoter’) apple shows a high sensitivity to internal browning disorders during CA-storage. To investigate the reasons and to develop optimal storage conditions for the ‘Kanzi’ apple, storage experiments have been carried out for five 5 years. Fruit were picked from different orchards at up to four different harvest dates. After harvest apples were stored at various temperatures (1, 2, 3 or 5°C), and at different O2- (1 and 3 kPa) and CO2-partial pressures (0.7, 1.5, 2.0 and 3.0 kPa). In addition, a delayed establishment of CA conditions (7 or 21 days) was compared with a CA, employed immediately after harvest. After 4 to 8 months storage plus 7 d shelf-life at 20°C the influence of the tested factors on storability and fruit quality attributes (firmness, TA, TSS and skin colour) as well as on the incidence of browning disorders was investigated. Mineral analyses were carried out to find possible correlations between the mineral status of the fruit and the occurrence of internal browning. Results showed that ‘Kanzi’ apple is very sensitive to low temperatures and to increased CO2 partial pressure during CA storage. Apple stored at 3°C showed significantly less incidence of internal browning compared to fruit from 2 or 1°C, respectively, without having a negative influence of the increased temperature on fruit quality attributes. In a similar manner, increasing CO2 partial pressure (>1.5 kPa) led to an increase of the browning symptoms compared to apple stored at 0.7% CO2. The application of delayed CA-conditions did not show any positive effect in reducing the symptoms, but the sensitivity for internal browning was significantly increased with later harvest dates. Fruit mineral status did not appear to be correlated with sensitivity to internal browning symptoms. For ‘Kanzi’ apples, from the Lake Constance region, storage temperatures of 3°C, 1 kPa O2, E‚1 kPa CO2 and a CA start immediately after room filling seem to be suitable to reduce the occurrence of internal browning and to maintain fruit quality during long term storage.

Internal browning disorder and fruit quality in modified atmosphere packaged ‘Bartlett’ pears during storage and transit

Internal browning (IB) can be a serious problem with the use of modified atmosphere packaging (MAP) for ‘Bartlett’ pears (Pyrus communis L.) grown in the Pacific Northwest during storage and transit to distant markets. To investigate this disorder, ‘Bartlett’ pears harvested at commercial maturity were packed in a commercial MAP (MAPc), an experimental MAP (MAPe) and commercial perforated plastic bags (control) and stored in air at −1.1°C. After 1 and 3 months of storage, samples of MAPc and control fruit were transferred to rooms at temperatures of 2, 4.5, 7.5, and 10°C for 3 weeks to simulate transit temperatures and the time required to reach distant markets. MAPc maintained an average internal atmosphere of 12.3% O2+5.6% CO2 and significantly extended ‘Bartlett’ pear storage life with high eating quality and without IB and other disorders for up to 4 months at −1.1°C. The internal gas atmosphere of MAPe equilibrated at 2.2% O2+5.7% CO2, which resulted in fruit with 25.5 and 62.3% IB after 3 and 4 months of storage, respectively. During simulated transit conditions of 2, 4.5, 7.5, and 10°C, the CO2 level in MAPc was maintained at 5.6–7.9%, while O2 was reduced dramatically to 10.5, 5.0, 2.5, and 1.0%, respectively. IB developed at 7.5 and 10°C but not at 2 and 4.5°C, regardless of pre-transit storage duration (1 and 3 months) at −1.1°C. The longer the storage duration and the higher transit temperature, the higher the incidence and severity of IB. The MAP-related IB disorder observed in this study included two types of symptoms: classic pithy brown core and wet brown flesh. The MAPc storage gas atmospheres maintained fruit firmness, color and higher eating quality after ripening, eliminated senescent scald and core breakdown, suppressed the loss of ascorbic acid (AsA) and titratable acidity, and slowed the accumulation of malondialdehyde (MDA) during storage at −1.1°C for up to 4 months or 3 months+3 weeks at simulated transit temperatures of 2 and 4.5°C. In contrast, fruit held in MAP with low O2 levels (1.0–2.5%) developed IB that appeared to be associated with a reduction in AsA, accumulated MDA and exhibited an increase in membrane leakage. MAP inhibited ripening at high CO2+high O2 but lead to IB when the packaging material or elevated temperatures resulted in high CO2+low O2 conditions. The incidence of IB closely correlated with lipid peroxidation and appeared to be related to fruit AsA concentration. The MAPc designed for pears appears to be suitable for ‘Bartlett’ fruit stored at −1.1°C for up to 4 months or storage for 3 months and a transportation duration of up to 3 weeks at 0–4.5°C during the early season and at 0–2°C during the late packing season. These conditions yielded fruit of high eating quality and without IB or over-ripening upon arrival at distant markets.

High-throughput NMR based metabolic profiling of Braeburn apple in relation to internal browning

NMR is a valuable tool for metabolomics due to its short analysis time and reproducibility. However, this technique remains little used due to its high cost. Recently, cheaper NMR machines for high-throughput screening have been developed. In this study, NMR was used to study the effect of several pre- and postharvest factors on apple metabolite levels during air and controlled atmosphere storage, including metabolic changes related to the incidence of internal browning. The results show that the selected fertilizer treatments and fruit side (green versus red side) did not affect the metabolite levels. However, the different postharvest storage conditions (optimal CA and brown inducing CA) did result in significant changes in metabolite levels. In addition, differences (e.g., pyruvate, citrate, fumarate, alanine, chlorogenate, methanol, ethanol, acetaldehyde and acetoine) between brown and unaffected apples stored under the applied CA conditions could be demonstrated.

Effects of Rapid Consecutive Postharvest 1-Methylcyclopropene Treatments on Fruit Quality and Storage Disorders in Apples

The objective of this study was to investigate the effects of rapid consecutive 1-methylcyclopropene (1-MCP) treatments on apple quality and disorders in storage. ‘McIntosh’ and ‘Spartan’ apples were harvested twice from commercial orchards and 1-MCP (1 μL·L−1) was applied postharvest either 1 day after harvest or 1 and 2 days after harvest. Similar fruit from both cultivars were also not treated with 1-MCP, plus an additional treatment of 2 μL·L−1 (double rate) 1-MCP was used on ‘McIntosh’. Fruit were held in either air storage at 0.5 °C for three or six months or in controlled-atmosphere (CA) storage for six or nine months. Overall, 1-MCP treatment improved firmness and acidity retention and reduced internal ethylene in both cultivars. However, ‘Spartan’ stored in CA often maintained these attributes without 1-MCP. ‘McIntosh’ apples treated twice with 1-MCP were often firmer than those treated just once. All 1-MCP treatments substantially reduced superficial scald and there was no difference in scald incidence among the treatments. Core browning was generally reduced by 1-MCP, but fruit treated once with 2 μL·L−1 or twice with 1 μL·L−1 1-MCP sometimes had higher incidence than fruit treated only once with 1 μL·L−1. ‘Spartan’ treated twice with 1-MCP also had higher incidence of internal browning after nine months. 1-MCP increased the incidence of external CO2 injury in ‘McIntosh’ from the first harvest, with fruit treated with 2 μL·L−1 having the highest incidence after six months of CA storage and those treated once with 1 μL·L−1 having the highest incidence after nine months. Storage rots were greatest after six months of air storage and 1-MCP treatments usually reduced the incidence, regardless of treatment. These results suggest that using more than the traditional single application of 1 μL·L−1 1-MCP may improve firmness retention, but there is also some risk associated with increased disorders, especially when storing apples long-term, such as for six months in air or nine months in CA storage.

Quality changes and internal browning developments of summer pineapple fruit during storage at different temperatures

The influences of storage temperature on quality parameters, comprising total soluble solids (TSS), free sugars, vitamin C, titratable acidity (TA) and soluble proteins, and internal browning (IB) of summer pineapple (Ananas comosus L. cv. ‘Comte de Paris’) fruit were investigated. The fruit were subjected to three different temperatures (6, 10 and 25°C) with relative humidity of 80% for 24 days. In addition, the activities of polyphenol oxidase (PPO), peroxidase (POD) and catalase (CAT) were measured during storage. The results indicated that a decrease in TSS in fruit kept at 25°C was noted, while TSS remained relatively constant in fruit storage temperature at 10 and 6°C. A high correlation was observed between the different sugars during storage periods. There was a noticeable decline in sucrose content in pineapple fruit during storage, with a more rapid decrease with higher temperature. The maximum retentions of glucose and fructose concentrations can be achieved with storage of fruit at 6°C rather than storage at 10 or 25°C. The effective slowing down of vitamin C and TA rate of decreases was the fruit stored at 6°C, followed by 10 and 25°C. There was a decrease in contents of soluble proteins as storage temperature increased throughout the storage period, and significant differences were found between fruit stored at low temperature and room temperature after 12d in storage. Storage temperature also significantly affected IB development, the incidence of IB was more rapid and with higher intensity in fruit held at 25°C than 10°C, and IB intensity was minimal in fruit held at 6°C. Additionally, PPO activity increased with higher storage temperature during 24 days storage. CAT activity gradually increased at three storage temperatures and in the fruit stored at 25°C was higher than those at 10 and 6°C. However, POD activity was not influenced by storage condition. The results suggest that lower temperature can provide a useful means of maintaining quality and resist IB development during storage of pineapple fruit.

동양배 '원황' 및 '화산'의 상온유통 중 품질 및 생리장해 발생에 미치는 1-methylcyclopropene (1-MCP) 처리의 영향

본 연구에서는 1-MCP 처리가 조생종 '원황' 및 중생종 '화산 '배의 상온유통기간 중 과실품질 및 생리장해 발생 경감에 미치는 영향을 조사하였다. '원황' 배는 만개 후 130일과 140일에, '화산' 배는 만개 후 135, 145 및 150일에 각각 수확하여 실험에 이용하였다. 1-MCP를 <TEX>$1{\mu}L{\cdot}L^{-1}$</TEX> 농도로 처리한 후 <TEX>$25^{\circ}C$</TEX> 상온에서 21일간 유통시킨 후 과실경도를 조사한 결과, 1-MCP 처리에 의한 과실 경도 저하 지연효과가 인정되었다. '원황' 배에 있어 만개 후 130일에 수확한 과실의 경우, 무처리구의 과실 경도는 상온유통 14일 후 32.3 N, 21일 후 10.1N으로 유통기간이 경과하면서 경도가 급격하게 저하되었다. 1-MCP 처리구는 같은 조사 기간에 각각 39.4 및 33.1N으로 무처리구에 비해 유의하게 높게 유지되었다. 만개 후 140일에 수확한 '원황'에 있어서는 상온유통 14일에 각각 14.8 및 35.0N으로 1-MCP 처리구의 경도가 두 배 이상 높게 유지되었고 유통 21일에는 1-MCP 처리구가 33.3N이었던 반면 무처리구는 6.6N으로 상품성을 완전히 상실하였다. '화산'에 대한 1-MCP 처리 효과는 수확시기가 늦은 과실에서 효과가 크게 나타났다. '원황'에 대한 1-MCP 처리는 각 수확기에 있어 가용성고형물 함량이 높게 유지되는 경향을 보였는데 '화산'에 있어서는 1-MCP 처리에 따른 함량차이는 인정되지 않았고 1-MCP 처리에 의한 산함량 감소지연효과도 '원황'에서만 나타났다. 에틸렌 발생량은 '원황'의 경우 수확시기가 늦은 과실에서 다소 높게 측정되었으나 최대 <TEX>$0.58{\mu}l{\cdot}L^{-1}$</TEX>으로 매우 소량에 머물렀는데 '화산'의 경우에는 '원황'에 비해 현저히 낮은 수준으로 검출되었고 1-MCP 처리유무 및 유통기간의 경과에 따른 유의한 변화가 없었다. 유통기간 중 1-MCP 처리에 따른 과실의 호흡량은 '원황'에 대한 1-MCP 처리는 만개 후 130일 및 140일 수확 과실에 있어서 상온유통 14일에 무처리구 대비 각각 44 및 50% 감소시킨 것으로 조사되었다. '화산'의 호흡량은 '원황'에 비해 유의하게 낮은 수준으로 조사되었고 1-MCP 처리에 따른 호흡률의 감소는 관찰되지 않았다. 과실내부에 발생하는 생리장해를 측정한 결과, 두 품종 모두 수확시기가 늦어지는 경우 증가하는 경향이었다. '원황'에 있어 만개 후 130일 수확 과실에 대한 1-MCP 처리는 과육갈변을 완전히 방지하였고, 바람들이 및 과심갈변의 발생을 현저히 경감되었던 반면 flesh spot decay 장해는 증가하였다. 1-MCP 처리는 '원황'에서만 생리장해 경감효과가 나타났고 상대적으로 '화산'에서는 그 효과가 다소 떨어지는 것으로 조사되었다. This study was conducted to investigate the effect of 1-methylcyclopropene (1-MCP) on fruit quality and incidence of physiological disorders for keeping freshness during marketing period in Asian pear (Pyrus pyrifolia Nakai) 'Wonhwang' and 'Whasan'. Fruits were treated with <TEX>$1{\mu}L{\cdot}L^{-1}$</TEX> 1-MCP for 12 hours at <TEX>$25^{\circ}C$</TEX>, at two or three stages of ripeness as determined by days after full bloom (DAFB). Fruits were harvested at 130 and 140 DAFB in early season cultivar 'Wonhwang' and 135, 145, and 150 DAFB in mid-season cultivar 'Whasan', respectively. Fruits were stored at <TEX>$25^{\circ}C$</TEX> for 21 days and measured the flesh firmness, weight loss, soluble solids, acidity, ethylene, respiration and severity of physiological disorders at week interval. 1-MCP treatment to 'Wonhwang' pears harvested at 130 and 140 DAFB effectively delayed firmness loss during storage at <TEX>$25^{\circ}C$</TEX>. Untreated fruits of 'Wonhwang' pears harvested at 130 DAFB showed 32.3 and 10.1N of firmness after 14 and 21 days of shelf-life at <TEX>$25^{\circ}C$</TEX>, respectively, while those of the 1-MCP treated fruits showed 39.4 and 33.1N during same period. In the fruits harvested at 140 DAFB, the firmness of untreated fruit was lowered to 14.8 and 6.6N after 14 and 21 days, respectively, but those of 1-MCP treated fruit were 35.0 and 33.3N, respectively. Whereas, 1-MCP treatment delayed firmness loss only in the fruit harvested late (150 DAFB) in 'Whasan' pears. Higher soluble solids content and acidity during extended shelf-life were apparent in 1-MCP treated 'Wonhwang' pears, while those of 'Whasan' pears were little changed. 'Wonhwang' pears showed a relatively high ethylene production (maximum <TEX>$0.58{\mu}l{\cdot}L^{-1}$</TEX>) in the fruits harvested late than early harvested one. 'Whasan' pears showed little amount of ethylene production regardless of extended shelf-life. 1-MCP treatment to 'Wonhwang' pears decreased respiration rate following shelf-life, 42 and 50% reduction were observed at 14 days of shelf-life when compared with those of untreated ones harvested at 130 and 140 DAFB, respectively. No reduction of respiration rate by the treatment of 1-MCP was detected in 'Whasan' pears which showed considerably low respiration rate compared with 'Wonhwang' pears. Harvest time influenced the level of physiological disorders together with extension of shelf-life in both the cultivars. 1-MCP treatment completely blocked the incidence of internal browning of 'Wonhwang' pears harvested at 130 DAFB, and reduced the incidences of pithiness and core browning, while it promoted the flesh spot decay disorder regardless of harvest time. 1-MCP treatment was of little benefit for the prevention of physiological disorders in 'Whasan' pears compared with those of 'Wonhwang'.

Internal browning of pineapple (Ananas comosus L.) fruit and endogenous concentrations of abscisic acid and gibberellins during low temperature storage

The relationship between internal browning (IB) and changes in endogenous abscisic acid (ABA), endogenous gibberellin (GA) [gibberellin A1 (GA1), gibberellin A3 (GA3) and gibberellin A4 (GA4)] concentrations were investigated using pineapples (Ananas comosus L. Merr; cv. Trad-see-thong and cv. Pattavia). The fruits were subjected to three different storage temperature conditions for 21d: at 10°C, 25°C, or 10°C with 1d at 25°C on either the 7th, 14th, or 21st day. In the fourth experiment, both cultivars were stored at 25°C, but were treated with GA3 or water (a control treatment) immediately before storage. In both cultivars, the polyphenol oxidase (PPO) activity was correlated with the degree of IB and was highest in fruit transferred from 10°C to 25°C. Endogenous ABA concentrations were significantly increased during storage at 10°C and decreased after the fruit was transferred from 10°C to 25°C in both cultivars. In contrast, endogenous total GA (GA1+GA3+GA4) concentrations were significantly increased after the fruit was transferred from 10°C to 25°C. Trad-see-thong pineapple, which had higher endogenous ABA during storage at 10°C and higher GA concentrations after being transferred from 10°C to 25°C, showed a high IB incidence. In both cultivars, fruit treated with 433μM GA3 showed higher IB and PPO activity than untreated controls during storage at 25°C. In addition, GA3 application significantly increased the endogenous ABA concentration in the Trad-see-thong pineapple at 25°C. The results suggest that endogenous ABA may be associated with the resistance response to IB in pineapples and GA concentrations may be factors that influence IB in pineapples.

Pre- and post-harvest salicylic acid treatments alleviate internal browning and maintain quality of winter pineapple fruit

The post-harvest internal browning (IB) and quality in pineapple ( Ananas comosus L. ‘Comte de Paris’) fruit were studied in relation to pre-harvest salicylic acid (SA) spray (PSS) or/and post-harvest salicylic acid immersion (PSI) treatments at 10 °C for up to 20 days plus 2 days at 20 °C (shelf-life). In addition, the activities of polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) were measured during cold storage. The results showed that all SA treatments significantly reduced IB incidence and intensity. Furthermore, SA did not affect soluble solids content (SSC), titratable acidity (TA) and total phenolics (TP) content, but delayed the decline of ascorbic acid (AsA) content. At the same time, SA significantly inhibited PPO and PAL activities. The study indicated the beneficial effect of SA by pre-harvest spray and/or post-harvest immersion on pineapple fruit quality and resistance to IB, and PSS + PSI treatment showed the best effect.

Qualidade de maçãs 'Fuji' armazenadas em atmosfera controlada e influência do clima na degenerescência da polpa

O objetivo deste trabalho foi avaliar a qualidade de frutos e a relação entre condições climáticas durante o desenvolvimento dos frutos e incidência de degenerescência da polpa no armazenamento em atmosfera controlada (AC) de maçãs 'Fuji'. Foram utilizados frutos de três pomares (Vacaria, RS, e São Joaquim e Lages, SC) e de dois anos agrícolas (2006/2007 e 2007/2008). Durante o desenvolvimento dos frutos, os pomares foram monitorados diariamente, quanto a temperaturas mínimas, médias e máximas, umidade relativa e precipitação. Os frutos foram armazenados por oito meses em diferentes condições de AC, a -0,5±0,1ºC e umidade relativa de 97%. Foram estimadas as correlações de Pearson entre as variáveis relativas às condições climáticas e a incidência de degenerescência da polpa após o armazenamento sob AC. Frutos armazenados sob 1,2 kPa de O2 e 2,0 kPa de CO2 apresentaram maior acidez titulável, firmeza de polpa e textura e menores taxas respiratória e de produção de etileno; exibiram, porém, alta incidência de degenerescência da polpa, em comparação aos armazenados sob 1,2 kPa de O2 e &lt;0,5 kPa de CO2. A incidência de degenerescência da polpa diminui com o aumento nas temperaturas médias diárias, ocorridas entre 90 e 210 dias após o pleno florescimento.

Preharvest aminoethoxyvinylglycine treatments reduce internal browning and prolong the shelf-life of early ripening pears

The effect of aminoethoxyvinylglycine (AVG) on internal browning (IB) and keeping quality of early maturing European pears cv ‘Camusina di Genova’ and ‘Camusina di Bonarcado’ was examined over 10 days of storage at 18 °C. AVG was applied at 125 or 250 mg/L 2 weeks before harvest. At harvest fruit treated with AVG was less ripe than control fruit, being significantly firmer and experiencing lower values of maturity stage (based on ground color), maturity index (calculated value) and IB, depending on the AVG dose and cultivar. During storage, there was no treatment-dependent difference in titratable acidity and total soluble solids of juice, while both treatments reduced ethylene and respiration rates, delayed the ripening process and lowered the incidence of IB and the loss of firmness, especially when applied at 250 mg/L. In addition, AVG treatment significantly reduced decay development in both cultivars, mainly when it was applied at 250 mg/L. This effect was related to the delay of ripen and to possible inhibition of ethylene production by the pathogens and/or infected tissues.

ASCORBIC ACID AND TISSUE BROWNING IN MANGO CV HINDI BE-SENNARA FRUITS (Mangifera indica L.) UNDER COLD STORAGE

This study was conducted to find out the relationship between ascorbic acid (AA), and internal browning (IB) incidence in Hindi Be-sennara mango fruits (Mangifera indica L.) during cold storage (4oC). Ascorbic acid content in two main parts (stem and calyx end of fruit) and three sub-main parts (peels, inner and outer pulps) of the fruits were measured. Internal browning in mango fruits found to be dependant on the fruit AA content. Exogenous application of AA (5.6 mM) decreased IB incidence when the fruits immersed for 24 hour compared to these immersed in water for the same time and stored at ambient conditions for 35 days. Mango fruits pre-storage immersing in diluted AA (5.6 mM), water is absorbed throughout the peel cells causing an increase on AA content and a decrease on its concentration. The decrease of IB incidence was appeared due to such increase on AA content in inner and outer parts of the fruit. This protection of the treated fruits may be related to the consumption of the externally added AA. Therefore, it could be said that the application of AA increases mango fruit quality, through protecting the from development of IB, also, the obtained results indicated that such treatment maintain the total phenols (TP) content in fruits during cold storage constant.

Correlation and path-coefficient analyses of ripening attributes and storage disorders in ‘Ambrosia’ and ‘Empire’ apples

The objectives of this study were: (1) to determine correlation effects among the ripening attributes of ‘Empire’ and ‘Ambrosia’ apples during storage, and (2) to determine the direct and indirect contributions of these ripening attributes on the incidence of physiological disorders and storage rots using path-coefficient analysis. The analysis was applied to data obtained from a variety of harvest dates and storage regimes from apples. Pearson correlation analysis of the data indicated a strong positive correlation between internal ethylene concentration (IEC) and peel greasiness, a negative correlation between IEC and soluble solids concentration, and a negative correlation between firmness and peel greasiness in both cultivars, as well as a negative correlation between IEC and firmness in ‘Empire’. Results indicated that increased IEC in ‘Ambrosia’ apples during storage was related to higher incidences of core browning and lenticel damage and lower incidence of internal browning. Higher IEC in ‘Empire’ apples during storage was associated with less internal browning. Several significant correlations, representing different relationships among the ripening attributes and storage disorders were obtained.