• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1529-1529
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• 2001

The watercore in apple is very important factor in storage and sorting of fruit. Most consumers tend to prefer the apple included watercore in immediately after harvest, however the watercore causes fruit flesh to brown during storage and lose the worth after all. But it is practically impossible to judge to the naked eye whether an apple has watercore or not. Therefore, the rapid, accurate and non-destructive analysis method for discrimination of watercore should be settled without delay. In this study we attempted the discrimination and quantitative analysis of watercore in apple fruit using near-infrared transmittance spectroscopy ‘Fuji’ apple fruits produced in Kyungpook of Korea was used in this experiment. The watercore content in apple was evaluated by graphic treatment of culled slice sections(10 mm). NIR transmittance spectra were collected over the 500 to 1000 nm spectral region with a spectrometer (Sentronic Co., Germany). The calibration models were carried out by partial least squares (PLS) analysis between NIR spectra data of apples and chemical data of watercore content. The spectra were different in absorbance between apple included watercore and not included one. Apple included watercore had higher absorption band than sample not included one at 732 and 820 nm. The calibration model seems to be accurate to predict the watercore content in apple fruit, the correlation coefficient (R) and root mean square error of prediction (RMSEP) were 0.99 and 0.93%, respectively. This result indicates that the PLSR calibration model by using NIR transmittance spectroscopy could be used for discrimination of watercore in apple fruit.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.118-124
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• 2008

Skin sooty dapple disease, a fungal disease that lowers Asian pear fruit quality, has emerged recently in Korea but has not yet been thoroughly characterized. This disease affects the surface of fruit, leaves, and young shoots of the Asian pear, typically appearing as a dark or pale black dapple on the fruit surface. The disease initiates on the fruit with small circular lesions that become bigger, eventually spreading to form large circular or indefinite lesions. Sparse dark or flourishing white-greyish aerial mycelia and appearance of a dark or pale black dapple on the fruit surface are typical signs of this disease. The disease was severe during cold storage of the Niitaka and Chuhwangbae varieties, but more limited on the Gamcheonbae and Hwangkeumbae varieties. To identify causal pathogens, 123 fungal isolates were obtained from lesions. The fungi that caused typical skin sooty dapple disease symptoms in our bioassay were identified. Based on their morphological characteristics, 74% of the isolates were Cladosporium sp. and 5-7 % of the isolates were Leptosphaerulina sp., Tripospermum sp., or Tilletiopsis sp. None of the isolates caused severe soft rot by injection to a wound plug, but some of the Cladosporium sp. isolates caused mild maceration. Therefore this microbiol complex cannot account for the soft rot also observed in stored fruits. The high frequency of isolation of Cladosporium sp. from disease tissues and bioassay on pear fruit surface suggest that Cladosporium sp. could be a major pathogen in the microbial complex associated with skin sooty dapple disease of the Asian pear in Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.2-3
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• 2003

A method for rapid propagation of mature Jack fruit was developed. Four types of explants (mature embryos, apical meristems of young seedlings, apices from mature plants and nodal segments) were used. It has been found 88% of young apical meristems produced shoots in Campbell and Durzan (CD) medium compared to 60% in Murashige and Skoog (MS) medium. Only 1/3 of them produced multiple shoots. Shoot initiation from nodal segments was very rare. Mature apices produced callus. Although removal of the sheathing cover around mature buds enhanced the shoot initiation but success rate was low in growth regulator free medium. Embryos respond to the CD medium but not to the MS medium. Embryos from seeds soaked in water for 24 hours produced shoots after 8 weeks of incubation and the success rate was 70% while embryos from dry seeds only produced roots. There was no significant effect of cold storage (refrigeration) for 7 days on shoot initiation from mature embryos (65%) but the ability for shoot induction declines with storage time (55% after 21 days of cold storage). Mature axillary buds were established in Modified Campbell and Durzan (CD) medium supplemented with 0.5mg/1 and IBA. There was a significant difference in the growth performance of shoots according to the period of the year in which explants were collected. Highest (60%) was observed in November-January period. It was only 30% when the explants were collected in February-April or May-July and decreased to 20% in August-October. The shoots produced in November-January showed a higher vigor than those produced in other months. Since Jak fruit show seasonal changes in fruit bearing and shedding of leaves, it can be suggested that the difference in growth performances of tissues cultured in artificial culture media would have been affected by endogenous rhythms.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.19-25
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• 1998

This study was conducted to develop an appropriate postharvest technique to extend the shelf-life of an early cultivar, 'Tsugaru' apples. The general quality of stored fruit was more affected by maturity at harvest than postharvest treatments. When firmness and internal quality were considered, fruits harvested at the medium stage of color development showed better results. Between postharvest treatments examined in this study, a simple polyethylene film(PE) wrapping (30um) was excellent on inhibition of weight loss but this treatment revealed no clear effect on other quality factors including firmness and acidity. Ethylene scrubber(ES) in polyethylene wrapping showed a positive effect on keeping fruit quality in general. Especially acid content was higher in fruit stored with PE + ES, thus, fruit seemed to be better in freshness. A physiological disorder was observed regardless postharvest treatments. The symptom was associated with incidence of pitting on surface and breakdown of the effected tissue. And much more symptoms were developed near the calyx end. Thus, future studies concerning 'Tsugaru' storage should include an examination of the optimum storage temperature.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.300-313
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• 2017

'Unicon' cherry tomato (Solanum lycopersicum) is one of the most highly perishable horticultural crops due to its high water content and respiration rate. This study was carried out to assess the effect of continuous application of $CO_2$ (control [air], 3%, and 5%) on the quality and shelf life of cherry tomato fruits stored at $10^{\circ}C$ and $85{\pm}5%$ relative humidity (RH) at two maturity stages (pink and red). Continuous application of $CO_2$ did not affect the soluble solids content (SSC) or titratable acidity (TA) of the fruit at either maturity stage during storage. However, there was a significant difference among treatments in terms of flesh firmness, cell wall thickness, pectin content, vitamin C content, skin color, lycopene content, weight loss, ethylene production rate, respiration rate, and acetaldehyde and ethanol production. Fruits treated with 5% $CO_2$ maintained their high quality with regards to vitamin C, skin color ($a^*$), lycopene content, weight loss, physiological parameters (ethylene production rate, respiration rate, and volatile compounds), flesh firmness, cell wall thickness, and pectin content at both maturity stages compared with 3% $CO_2$ treatment and the control. Continuous application of $CO_2$ (5%) reduced the ethylene production rate and the production of volatile compounds during storage. Therefore, cherry tomato 'Unicon' fruit can be stored for two weeks without losing fruit quality at both maturity stages under continuous application of 5% $CO_2$ as a postharvest treatment.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.136-144
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• 1992

This study was aimed to extend the marketing period through the postharvest application of fruit coating materials in early cultivar 'Tsugaru' apples. Postharvest application of fruit coating materials were effective on remaining freshness during storage and marketing. Prestorage waxing showed higher flesh firmness and weight loss was greatly reduced after storage. This tendency was continued even after marketing period. While no clear effect of prestorage Prolong application on keeping freshness was found, poststorage application of Prolong appeared to be most effective on the prevention of weight loss and keeping firmness during marketing. Parts of fruit developed $CO_2$ injury - like disorder regardless posthavest treatments but no trial was conducted to examine this disorder in this study. Further study should include to determine the cause of this disorder.

• Food Science and Preservation
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• v.16 no.6
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• pp.838-842
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• 2009

We explored how 'Wonwhang' pear fruit quality was affected by selenium (Se) application. The fruit skin color and fruit type differed between Se-treated trees and controls. Se-treated fruits had higher potassium and Se concentrations, more fruit soluble solids, and lower acidity, compared to the controls. All Se treatments improved fruit firmness during cold temperature storage compared to the controls. Also, Se-treated fruits had greater specific gravity and minuteness, which reduced fruit pithiness and rendered test fruits denser than the controls. Overall, Se foliar application improved fruits marketability compared to the Se fertilization or Se trunk injection.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.74-79
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• 1995

This study was made to investigate the effects of soil moisture content according to irrigation methods on the storability and quality of cucumber. The fresh weight loss of cucumber fruit harvested in drip irrigation plot was more than that in conventional irrigation plot at both 13$^{\circ}C$ and 24$^{\circ}C$ storage temperature. Dry weight ratio decreased during storage, and was higher in conventional irrigation plot than drip irrigation plot both 13$^{\circ}C$ and 241 storage. The decrease of dry weight ratio was higher at 24$^{\circ}C$ than 13$^{\circ}C$. Vitamin C was not influenced by soil moisture content, but decreased during storage at 13$^{\circ}C$ and 24$^{\circ}C$ The decrease of vitamin C at 24$^{\circ}C$ in 8 days after storage was twice as much at 13$^{\circ}C$. Firmness was measured differently in two parts of cucumber ; fruit stalk and blossom part. The firmness of fruit stalk part was higher than that of blossom part. This phenomena was observed continuously at until final day at 13$^{\circ}C$ and 24$^{\circ}C$ storage. But the difference of firmness was not showed in soil moisture content. Vitamin C, firmness and other quality characteristics were not influenced by soil moisture content during cultivation. The different soil moisture content according to irrigation methods did not affect the storability and quality of cucumber.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.177-183
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• 2006

The summer production of sweet pepper in Korea which cultured in the highland area such as Hapchon is essential for a year-round export, but has the problem, fruits lose easily those marketability. This study was carried out to find changes of fruit quality in response to storage on sweet pepper cultivars in summer. Seven cultivars of sweet peppers, 'Jubilee', 'Plenty', 'Goal', 'Romeca', 'Derby', 'Midas' and 'Maximalia' were obtained iron growers in Hapchon which was highland of 600-800m from sea level and stored at $10^{\circ}C$ with box packing. Fruit quality was evaluated every 4days up to 4weeks. The weight loss of 'Jubilee' was the lowest, that of 'Romeca' was the highest. The firmness of 'Goal' was maintained highly for 4weeks and the red cultivars was higher than those of other color cultivars. The lightness of 'Jubilee' was sensitively affected by storage duration. Seeds of 'Plenty' and 'Derby' were plentifully browned after 4weeks storage. The occurrence of fruit rotting was after 16-204ay storage and those of 'Plenty' and 'Maximalia' were the earliest. The marketability of 'Jubilee' and 'Romeca' maintained by 70% for 16 days was the highest, but most cultivars lost those by 20% after 24days storage. It may be suggested that the marketability of sweet pepper producted in summer can be stored at $10^{\circ}C$ for 2weeks to maintain that of 80%.

• Food Science and Preservation
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• v.8 no.3
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• pp.252-257
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• 2001

This studies were carried out to investigate the physical properties and quality of sweet persimmon fruits which packaged with polyethylene for improvement of quality and storage. The fruits which packed 5 fruits a pack by 0.06mm PE film was maintained freshness during 120 days of storage, but those which packaged a fruit was maintained freshens during 150 days of storage, and quality of fruits was excellent during storage. It was more excellent quality of fruits packaged 5 fruits a pack with 0.08 and 0.10mm PE film than quality of those packaged by 0.06mm PE film. Hardness of fruits were decreased during storage, and the color of fruits was changed. But the fruits which packaged each with 0.08mm PE film was maitained freshens during 180 days of storage, and the quality of fruits was excellent during storage. The hardness and color of fruits were net changed during storage.