• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2004.10a
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• pp.67-72
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• 2004

Quality of fresh-cut tomato slices was compared during cold storage under various modified atmosphere packaging conditions. Chilling injury of slices in containers sealed with Film A was higher than with Film B; these films had oxygen transmission rates of 87.4 and 60.0 ml $h^{-1}\;m^{-2}\;atm^{-1}$ at $5^{\circ}C\;and\;99\%$ RH, respectively. While slices in containers with an initial atmospheric composition of air, $4\%\;CO_2+1\;or\;20\%\;O_2,\;8\%\;CO_2+1\;or\;20\%\;O_2,\;or\;12\%\;CO_2+20\%\;O_2$ showed fungal growth, slices in containers with $12\%\;CO_2+1\%\;O_2$ did not. Low ethylene in containers enhanced chilling injury. Modified atmosphere packaging provided good quality tomato slices with a shelf-life of 2 weeks or more at $5^{\circ}C$. Experiments were conducted to compare changes in quality of slices of red tomato (Lycopersicon esculentum Mill. 'Sunbeam') fruit from plants grown using black polyethylene or hairy vetch mulches under various foliar disease management systems including: no fungicide applications (NF), a disease forecasting model (Tom-Cast), and weekly fungicide applications (WF), during storage at $5^{\circ}C$ under a modified atmosphere. Slices were analyzed for firmness, soluble solids content (SSC), titratable acidity (TA), pH, electrolyte leakage, fungi, yeasts, and chilling injury. With both NF and Tom-Cast fungicide treatments, slices from tomato fruit grown with hairy vetch (Vicia villosa Roth) mulch were firmer than those from tomato fruit grown with black polyethylene mulch after 12 days storage. Ethylene production of slices from fruit grown using hairy vetch mulch under Tom-Cast was about 1.5- and 5-fold higher than that of slices from WF and NF fungicide treatments after 12 days, respectively. The percentage of water-soaked areas (chilling injury) for slices from tomato fruit grown using black polyethylene mulch under NF was over 7-fold that of slices from tomato fruit grown using hairy vetch under Tom-Cast. When stored at $20^{\circ}C$, slices from light-red tomato fruit grown with black polyethylene or hairy vetch mulches both showed a rapid increase in electrolyte leakage beginning 6 hours after slicing. However, slices from tomato fruit grown using the hairy vetch mulch tended to have lower electrolyte leakage than those grown with black polyethylene mulch. These results suggest that tomato fruit from plants grown using hairy vetch mulch may be more suitable for fresh-cut slices than those grown using black polyethylene mulch. Also, use of the disease forecasting model Tom-Cast, which can result in lower fungicide application than is currently used commercially, resulted in high quality fruit for fresh-cut processing. Experiments were conducted to determine if ethylene influences chilling injury, as measured by percentage of slices exhibiting water-soaked areas in fresh-cut tomato slices of 'Mountain Pride' and 'Sunbeam' tomato (Lycopersicon esculentum Mill.). Ethylene concentration in containers without ventilation significantly increased during storage at $5^{\circ}C$, whereas little or no accumulation of ethylene occurred in containers with one or six perforations. Chilling injury was greatest for slices in containers with six perforations, compared to slices in containers with one perforation, and was over 13-fold greater than that of slices in control containers with no perforations. An experiment was also performed to investigate the effectiveness of including an ethylene absorbent pad in containers on subsequent ethylene accumulation and chilling injury. While ethylene in the no-pad controls increased continually during storage of both 'Mountain Pride' and 'Sunbeam' tomatoes at $5^{\circ}C$ under modified atmosphere conditions, no increase in accumulation of ethylene was observed in containers containing ethylene absorbent pads throughout storage. The ethylene absorbent pad treatment resulted in a significantly higher percentage of chilling injury compared with the no-pad control. In studies aimed at inhibiting ethylene production using AVG during storage of slices, the concentration of ethylene in control containers (no AVG) remained at elevated levels throughout storage, compared to containers with slices treated with AVG. Chilling injury in slices treated with AVG was 5-fold greater than that of controls. Further, we tested the effect of ethylene pretreatment of slices on subsequent slice shelf-life and quality. In slices treated with ethylene (0, 0.1, 1, or $10\;{mu}L\;L^{-1}$) immediately after slicing, ethylene production in non-treated controls was greater than that of all other ethylene pre-treatments. However, pretreatment of slices 3 days after slicing resulted in a different pattern of ethylene production during storage. Ihe rate of ethylene production by slices treated with 1 L $L^{-1}$ ethylene 3 days after slicing was greater during storage than any of the other ethylene treatments. With slices pre-treated with ethylene, both immediately and 3 days after slicing, the rate of ethylene production tended to show an negative correlation with chilling injury. Chemical name used: 1-aminoethoxyvinylglycine (AVG).

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2004.03a
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• pp.163-167
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• 2004

• Research in Plant Disease
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• v.24 no.2
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• pp.113-122
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• 2018

Ripe rot, Botrytis storage rot and Sclerotinia rot are major fungal diseases that lead to deterioration of fruit quality in Korea. Ripe rot, which is caused by Botryosphaeria dothidea, affects harvested fruits during post-storage ripening, while Botrytis storage rot, caused by Botrytis cinerea, affects harvested fruits during cold storage, and Sclerotinia rot, caused by Sclerotinia sclerotiorum, mainly affects immature fruits on the trees. Major fungal fruit rots tend to affect yellow- and red-fleshed cultivars of kiwifruit more severely because of the sharp increase in their cultivation acreage in recent years in Korea. In this review, we summarize symptoms and epidemiological characteristics of the major fungal fruit rots and propose integrated management methods of the diseases that can be practically utilized at the farmers' orchards in order to prevent the diseases based on our research works and field experiences and the research works of others conducted during the last three decades worldwide.

• Journal of Biosystems Engineering
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• v.32 no.4
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• pp.269-275
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• 2007

In this study, ultrasonic transducers for non-destructive contact measurement of whole fruits were developed. The design parameters for ultrasonic transducer such as acoustical impedance of fruits, kinds of piezoelectric materials, ultrasonic wave frequency, and transducer diameter were investigated. In order to match the acoustical impedance between piezoelectric material and fruit, various materials were fabricated and evaluated. Also to control the sensitivity and bandwidth of the ultrasonic transducer, various backing materials were fabricated and evaluated. Especially, the wear plate of the ultrasonic transducer was designed and fabricated considering the curvature of fruit. The central frequencies of two developed ultrasonic transducers were about 100 kHz and 200 kHz, respectively. With the developed ultrasonic transducers, non-destructive evaluation of the fruit will be possible.

• Culinary science and hospitality research
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• v.18 no.2
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• pp.206-215
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• 2012

The results of influence on the saccharification and $Sikhea$ by adding mulberry fruit in this study are as follows. pH was decreased with the amount of mulberry fruit increased during the saccharification period. A significant change was not found after 4 hours of saccharification. It is considered that 4-5 hours was proper for saccharification because brix increased by more than 1 brix per hour up to 4 hours while there were little change after 5 hours. L was decreased while a and b values were increased in the Hunter' value of mulberry fruit $Sikhea$. The DPPH free radical scavenging activities and SOD-like activity of mulberry fruit $Sikhea$ were increased as the addition quantity of mulberry fruit increased. Anthocynin color pigment in mulberry fruit has the inhibiting effect on microbes. The preferences of mulberry fruit $Sikhea$ were 10% < 30% < 15% < 20% < 0% < 25%, and less than 25% of mulberry fruit addition seems to be desirable. The addition of mulberry fruit will help decrease the amount of sugar to use in $Sikhea$ because the sugar level of $Sikhea$ increases with the addition of mulberry fruit. It will also improve the preference for Sihkea by giving it better color and sourness.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.353-358
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• 2014

In order to obtain the basic data that could be used to evaluate the harvest time of new hardy kiwifruit cultivars (Actinidia arguta 'Saehan', 'Daesung' and 'Chilbo'), the seasonal fruit quality and ripening characteristics of hardy kiwifruit were investigated. Fruit sizes of 'Saehan', 'Daesung' and 'Chilbo' were increased from full bloom to 66 days, 85 days and 78 days, respectively. The growth curve of developing fruit of three cultivars showed double sigmoid. As a result of correlation analysis, the seed number per fruit showed a significant positive correlation with fruit weight (r = 0.94~0.97, p<0.01). Fruit length, width, thickness, weight, soluble solid content and titratable acidity were significantly different among the cultivars. Titratable acidity was increased from full bloom to harvest time and the titratable acidity of 'Saehan', 'Daesung' and 'Chilbo' were 1.77%, 1.22% and 1.37% on havest time, respectively. Optimal harvest time of 'Saehan' was 108 days (23 Sep.) after full bloom, those of 'Daesung' and 'Chilbo' were 92 (9 Sep.) days after full bloom.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.831-841
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• 2017

Different timings of coverage by a small paper bag at the young fruit stage were tested in order to evaluate the effect on the protection of fruit damage occurred by disease or pest, and quality deterioration during organic cultivation of 'Hwasan' (Pyrus pyrifolia Nakai) pear cultivar. The occurrence of four major moth populations and two major diseases in pears were monitored from April to September 2015. Among major moths and diseases, Grapholita molesta and pear rust were found often in the organic pear orchard, and they were observed frequently in May. Coverage by a small paper bag at the young fruit stage resulted in better fruit quality and a higher proportion of commercial fruits compared to a coverage timing of conventional paper bag. Interestingly, the fastest coverage timing of a small paper bag at the young fruit stage (when it was covered in April) showed the lowest occurrence of damaged fruits, which indicates that it successfully protected fruits from the damage caused by moths and diseases during April and May. Moreover, this timing of small paper bag coverage did not negatively affect the major qualitative and quantitative characteristics of fruits. These results suggest that early coverage by a small paper bag at the young fruit stage can be considered an efficient management strategy for organic cultivation of 'Hwasan' pear cultivar.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.733-739
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• 2004

Model for optimally dimensioned PE film bag was developed according to fruit size to maintain best quality of 'Fuyu' persimmon in modified atmosphere packaging (MAP) storage based on relationship between quality and oxygen and carbon dioxide in PE film bag. Harvested persimmons were graded into five sizes, and average weights were LL:261, L:217, M:188, S:168, and SS:154 g. Five fruit units of each grade were optimized in five PE film bag sizes of $150{\times}376,\;140{\times}357,\;130{\times}344,\;130{\times}333,\;and\;120{\times}3l8\;mm$. To minimize quality deterioration such as softening and discoloration, optimal oxygen and carbon dioxide concentrations in PE film bag were 0.5-1.0 and 6.0-8.0%, respectively, and optimal thickness of PE film bag according to fruit size were LL:45, L:50, M:55, S:60, and $SS:65\;{\mu}m$. For all fruit sizes, model for PE film bag area $(mm^2)$ was good quadratic simple equation by fruit weight (g): $Y=-4055.707+627.993X_1-0.701{X_1}^2$. Model far optimal oxygen and carbon dioxide (Y) concentration in PE film bag was suited to linear multiple equation by fruit weight $(X_1,\;g)$ and PE film thickness $(X_2,\;{\mu}m)$. Equations for oxygen and carbon dioxide concentrations (%) were $Y=5.798-0.0109X_l-0.0491X_2\;and\;Y=-2.427+0.01927X_l +0.09646X_2$, respectively.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.429-433
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• 2010

The effects of 1-methylcyclopropene (1-MCP) for controlling ripening processes such as weight loss, fruit softening, soluble solids content (SSC), titratable acidity (TA), and fruit skin color were investigated and also the possibility that 1-MCP can inhibit the development of brown rot was explored in 'Formosa' plum ($Prunus$ $domestica$ L.). Fruit were treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP on the day of harvest and one day after harvest for 16 h at ambient temperature ($20^{\circ}C$), followed by 14 days of shelf life. 1-MCP treatment delayed fruit softening, weight loss and changes in skin color and TA during the shelf life period, but did not affect SSC. These 1-MCP effects were similar with and without delayed treatment. 1-MCP treatment inhibited the development of brown rot caused by $Monilinia$ $laxa$ during storage. Our data shows that treatment delays of ${\geq}1$ day before 1-MCP application had no negative effect of fruit softening, fruit skin color, and TA at ambient temperature ($20^{\circ}C$). Overall, these results indicate that 1-MCP can be used to maintain the quality of non-refrigerated plums.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.383-386
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• 2000

To clarify the effects of application time of $GA_{4+7}$ paste (GA paste) on tree and fruit growth, fruit quality, and maturity of 'Kamcheonbae' and 'Whangkuembae' pears, GA paste of 25 mg each was applied directly to fruit stalk 25, 35, and 45 days after full bloom (DAFB). Later application of GA paste tended to increase the fruit weight of 'Kamcheonbae' pear. GA paste applied 45 DAFB increased the titratable acidity of the two cultivars. Fruit firmness of 'Kamcheonbae' was not affected by the GA paste treatment, while that of 'Whangkuembae' was increased by more than 20%. Fruit maturity of the two cultivars was hastened for 4 days by the GA paste treatment at any application time. Sharp increase in the fruit weight of the GA paste-treated 'Kamcheonbae' was noted from early July while that of control exhibited slow increase from early September. The initial growth pattern of 'Whangkeumbae' was similar to that of 'Kamcheonbae', but the growth slowed down from early September, regardless of the treatments.