• Food Science and Preservation
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• 제22권4호
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• pp.520-527
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• 2015

This study investigated the physiological activities of garlic extracts frozen at -20, -80, and $-196^{\circ}C$. To determine the optimum freezing temperature for maintaining garlic's physiological activity, antioxidant and antibacterial activities were investigated. The antioxidant activities were determined by DPPH radical scavenging ability, SOD-like activity, nitrite-scavenging ability, and reducing power. Total phenolic compounds and flavonoids of garlic extract frozen at $4^{\circ}C$ (control) were measured as $6.91{\pm}0.69{\mu}gGAE/g$ and $0.315{\pm}0.017{\mu}gQE/g$, respectively. Although the content of total phenolic compounds was not affected by the different freezing temperatures, the flavonoids contents of garlic extract frozen at $-20^{\circ}C$ were slightly decreased. The DPPH radical scavenging ability of garlic extracts (2 mg/mL) frozen at $-80^{\circ}C$ was 61%, whereas those frozen at $-20^{\circ}C$ and $-196^{\circ}C$ were 51%. SOD-like activity was slightly increased by freezing. However, the nitrite scavenging ability (18% at pH 3.0) and reducing power (OD700=1.6) were not affected by freezing temperatures. Antimicrobial activities did not show significant differences depending on freezing temperatures. Taken together, the physiological activities of the frozen garlic extracts were not significantly changed by the freezing temperatures; however, the antioxidant and antibacterial effects of the phenolic compounds and flavonoids were maintained at $-80^{\circ}C$. These results suggest that $-80^{\circ}C$ frozen garlic could maintain a higher quality than the conventional freezing method ($-20^{\circ}C$) without loss of physiological activities during the storage.

• Korean Journal of Agricultural Science
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• 제20권1호
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• pp.9-17
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• 1993

Postharvest treatments such as polyethylene film wrapping, ethylene scrubber, and fruit coatings were compared to find a potential effect on the fruit quality in 'Fuji' apples during storage and simulated marketing. Polyethylene film wrapping appeared to be excellent in preventing weight loss during storage but fruits lost weight at a high rate when exposed to ambient temperature during simulated marketing. Also, surface cracking disorder was observed in parts of film-wrapped fruit under marketing condition after storage of 21 weeks. Ethylene scrubber effectively removed ethylene in polyetheylene bags but this effect reduced along with the increase of storage time. Although Prolong-treated fruits were good in appearance at 12-week storage, no beneficial effect was found on the inhibition of weight loss during storage as well as marketing. In addition, wax-like substances were accumulated on the surface after storage of 21 weeks, resulting in the reduction of marketability. Water soluble wax seemed highly effective on the inhibition of weight loss during storage and marketing. However, parts of fruit were severely injured probably due to the high concentration of wax. Undamaged fruit showed excellent appearance in shape and flesh quality even after 21 weeks of storage. Further study is required to find the proper concentration of wax.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제9권6호
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• pp.1882-1888
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• 2008

Effects of 1-MCP(1-methylcyclopropene) on the postharvest life and fruit quality of cucumber 'Baekdadaki' were investigated. Cucumber were held at room and cold chamber($10^{\circ}C$) treated with several concentrations of 1-MCP. Physico-chemical characteristics such as fresh weight and firmness were greatly varied during storage, and the treatment with I-MCP(500ppb) showed the minimal loss of the values at harvest. The peel b value representing a senescence process was higher investigated in 1-MCP(250 and 1,000ppb treatment, and led to the apparent yellowing and softening after cold storage for 15 days. 1-MCP(500ppb) showed lower decay rate and better marketability of cucumber than other treatments after cold storage for 15 days. The respiration rate was higher found in cucumber treated with 1-MCP(250ppb) than in other treatment. Ethylene evolution was most detected in cucumber treated with 1-MCP(1000ppb) after room storage for 6 days. 1-MCP did not affect the production of ethylene in cucumber during room and cold storage.

• Korean Journal of Food Science and Technology
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• 제38권1호
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• pp.28-34
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• 2006

Effects of various surface sterilization and washing methods on sterilization of fresh chicory surface were evaluated. Fresh-cut chicory was washed with tap water for 1 min, 100 ppm chlorinated water, and 3 ppm ozonated water using mechanical washing machine for 3 min, packed with bi-axially oriented polypropylene (OPP 0.04 mm) film, and stored for 3 weeks at 4 and $10^{\circ}C$. Tap water washing resulted in approximately 1 log CFU/g reduction of microbial load, and ozonated water and chlorinated water treatments resulted in additional 2 log CFU/g reduction.

• Food Science and Preservation
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• 제11권3호
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• pp.304-312
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• 2004

Early harvested Satsuma mandarin (Citrus unshiu) was treated with hot air at 45$^{\circ}C$ for 2, 4, and 6 hours and stored at 5$^{\circ}C$ for 3 weeks and additional one week at 18$^{\circ}C$ (simulated shelf-life) in order to examine the effect of mild heat treatment on the storage quality of the citrus fruits. Quality attributes of the sample fruits evaluated during storage included the respiration rate, internal gas composition, pH, titratable acidity, soluble solids content, flesh weight loss, firmness, peel color, decay ratio, and sensory properties. The initial respiration rates, just after hot air treatment, were significantly higher in the heat-treated fruits compared to the untreated. However, during storage at 5$^{\circ}C$, the respiration rates showed a similar level in all treatments. Internal gas composition exhibited no significant difference between the heat-treated and untreated samples. Hot air treatment also exerted no significant effects on the pH, titratable acidity, soluble solid contents, flesh weight loss, firmness, and peel color of the fruits during the whole storage period. The decay ratio was manifestly lower in the heat-treated fruits than the untreated. For sensory attributes including visual and organoleptic quality, no significant difference was observed among sample fruits. Results suggested that mild heat treatment with hot air at 45$^{\circ}C$ for 4-6 hours could be used as an effective preconditioning method to keep the postharvest quality of Satsuma mandarin by reducing the decay incidence remarkably during storage.

• The Plant Pathology Journal
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• 제17권3호
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• pp.141-148
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• 2001

Postharvest decay of onion bulbs was examined by inspecting the commercial packages in the market or in storage. Bulb rot incidence was unexpectedly high, and onion bulbs with 1st quality grade were rotten most severely by 51%, followed by 32% for 2nd and 21% for 3rd grades. This indicates that larger bulbs had higher incidences of bulb rots. Major pathogens associated with basal and neck rots were Fusarium oxysporum and Aspergillus sp. or Botrytis allii, respectively, of which basal rot was most prevalent and damaging during storage. Among the epiphytic microorgani는 from onion plants, several Bacillus and Paenibacillus spp. and previously selected Pseudomonas putida and Trichoderma harzianum had inhibitory efficacy against bulb rot pathogens. Among these B. amyloliquefaciens BL-3, Paenibacillus polymyxa BL-4, and P. putida Cha 94 were highly inhibitory to conidial germination of F. oxysporum and B. allii. P. putida Cha 94, B. amyloliquefaciens BL-3, P. polymyxa BL-4, and T. harzianum TM were applied in the rhizoplane of onion at transplanting. Initially antagonist populations decreased rapidly during the first one month. However, among these antagonists, rhizoplane population densities of BL-3, Cha 94, and TM were consistently high thereafter, maintaining about 10$^4$-10$^{5}$ cells or spores per gram of onion root up to harvest time. The other bacterial antagonist BL-4 survived only for two months. TM was the most effective biocontrol agent against basal rot, with the number of rotten bulbs recorded at 4%, while that of the control was 16%. Cha 94 was effective for the first 20 days, but basal rot increased thereafter and had about the same control efficacy as that of BL-3 and BL-4. When the antagonists were applied to the topping areas of onion bulbs at harvest, TM was the most effective in protecting the stored onion bulbs from neck rotting. The second effective antagonist was BL-3. TM and BL-3 completely suppressed the neck rot in another test, suggesting that biocontrol of postharvest decay of onion using these microorganisms either at the time of transplanting or at harvesting may be promising.

• Proceedings of the Plant Resources Society of Korea Conference
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.108-108
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• 2019

느타리버섯은 전남 장흥군에서 병재배로 재배된 '곤지 7호' 느타리버섯 품종을 $3^{\circ}C$에서 1일간 냉각시킨 후 실험에 사용하였다. 이산화탄소 처리는 10mm 두께의 아크릴로 제작한 밀폐 챔버($40{\times}70{\times}40cm$)를 이용하여 CO2가스를 주입하여 내부의 CO2 농도를 $30{\pm}1%$로 조정하여 3시간 동안 밀폐시켰으며 $3^{\circ}C$ 저온 저장고에서 수행하였다. 처리 후 포장필름은 3처리로 하여 PVC랩, 재배농가에서 이용하는 필름인 $20{\mu}m$ OPP필름, $30{\mu}m$ OPP필름을 재료로 하여 산소투과율을 $5,000cc/m2{\cdot}day{\cdot}atm$로 조정한 필름(OPP5)을 사용하였다. PVC랩 처리는 스티로폼 트레이에 옮긴 후 균일하게 한 겹으로 둘렀고, OPP와 OPP5는 봉지에 옮겨 봉지 입구 4cm 안쪽을 비닐접착기로 열접착하여 밀봉하였으며 $3^{\circ}C$에 저장하면서 필름내부의 기체조성, 경도, 색도, 이취, 종합선도 변화를 조사하였다. 포장된 느타리버섯의 포장재 내 이산화탄소 농도는 저장초기 0.03%에서 점차 증가하여 저장 3일 후 PVC랩은 3.5~3.9%, 나머지 처리는 18%이상으로 증가하였으며 OPP필름보다 OPP5필름의 경우 포장재 내 이산화탄소 농도가 더 낮게 유지되었다. 생체중 감소는 PVC랩에서 저장 26일 후 9.9% 이하로 육안으로 보이는 시들음이 관찰되었으며 나머지 처리들은 저장 26일 후까지 1.6% 이하의 중량감소율을 보였다. 느타리버섯 갓 경도는 유지되었으며 줄기표면의 황색도 $b^*$값은 PVC랩에서는 증가 경향을, OPP나 OPP5에서는 유지 경향을 보였다. 느타리버섯의 이취 및 전체적인 품질은 무처리 후 PVC랩 포장은 저장 6일 후에 이취가 상품성 한계로 발생하였고 OPP5 포장은 포장재 중 가장 이취발생이 늦게 발생하였으며 CO2 처리에 의해 지연되는 것을 알 수 있었다. 이런 결과를 종합하여 느타리버섯의 $3^{\circ}C$ 저장 중 품질유지기간은 각 PVC랩(6일) ${\rightarrow}$ 30% CO2+PVC랩(7일) ${\rightarrow}$ OPP(10일) ${\rightarrow}$ 30% CO2+OPP(17일) ${\rightarrow}$ OPP5(20일) ${\rightarrow}$ 30% CO2+OPP5(22일)로 조사되었다. CO2처리 후 산소투과율을 $5,000cc/m2{\cdot}day{\cdot}atm$으로 조정한 미세천공(OPP5)필름이 가장 높은 전체적 품질점수를 나타내었으며 상대적으로 낮은 이취발생, 갈변과 갓무름이 적어 높은 점수를 얻는데 영향을 준 것으로 보인다.

• Horticultural Science & Technology
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• 제33권2호
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• pp.233-241
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• 2015

Kimchi cabbage 'Choon Gwang' cultivar that was grown in highlands in Gangneung was subjected to predrying, room cooling, and forced air cooling, and then packed with/without 0.02 mm HDPE film to investigate the effect of postharvest treatment on quality characteristics during 8 weeks storage at $2^{\circ}C$ (RH $90{\pm}5%$). Weight loss in forced air cooling and room cooling was lower than 3-4% with 0.02 mm HDPE film liner treatment during storage. However, it was only below 10% in room cooling without liner treatment and forced air cooling without liner treatment led to the highest weight loss, above 15%. Conversely, the control had lower weight loss than the others. SSC was $2-4^{\circ}brix$ for all treatments and there was no difference between postharvest treatments and liner treatments. Color index and firmness both showed no differences with/without 0.02 mm HDPE film and postharvest treatments. In sensory evaluation, forced air cooling with liner treatment was effective, with the highest score, especially in appearance and crispness. After 6 weeks, control kimchi cabbage without liner treatment was damaged seriously in appearance and the internal color had changed to brown. Room cooling and predrying with liner treatment changed the start of internal browning to after 8 weeks storage.

• Korean Journal of Medicinal Crop Science
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• 제21권5호
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• pp.334-341
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• 2013

Studies were carried to evaluated the influence of storage method by temperatures and fillers on yield and quality of seed rhizome in turmeric. Seed rhizome was stored at styrofoam box filled with rice hull and sand (3:1) or vermiculite for 30, 60 and 90 days at different temperatures (5, 10 and $15^{\circ}C$. compared to traditional method (rhizome only). Parameters were obtained for weight loss, cold injury, percentage of decayed in stored rhizome during storage periods. Also, the germination, growth pattern and yield from stored rhizome has been investigated. It was confirmed that storage of turmeric in stored with filled with vermiculite helps in prevention of rhizomes from microbial and fungal attack. The storage of rhizomes in styrofoam box without any filler at low temperature below $10^{\circ}C$. is not advocated due to heavy losses weight and decayed in management of postharvest for turmeric rhizome. Germination percentage, growth pattern and yield was maximum for rhizomes stored at styrofoam box filled with vermiculite for 90 days at $15^{\circ}C$. The paper outlines a brief attempt to assess the efficacy of non-chemical methods including optimal storage method (temperature and filler) of control of decay and moisture losses during storage of turmeric.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.26-32
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• 2003

Rice is one of the most important cereals in the world. Japanese people use about 9 million tons of rice per you. We use rice for cooked rice as staple foods and for processing, such as rice wine (sake), rice crackers and miso fermentation, etc. Palatability, eating quality, of rice is evaluated by the sensory test and various kinds of physicochemical measurements. Japanese National Food Agency started the storage of 1.5 million tones of rice in 1996. We carried out the storage test using high quality rices since 1995 until 1996. As indices for the quality deteriorations of rice grains during the storage, germination ratio, enzyme activities, fat acidity, physical properties of cooked rice were clarified to be useful. We applied colorimetric method for the measurements of fat acidities in the place of titration method. Processing suitabilities of rice differ depending on the products. Low amylose rice is more suitable for soft rice crackers and high amylose rice is preferred more for rice noodle. Pre-cooked rice products, such as frozen cooked rice, retort-pouched rice and aseptic rice, are increasing recently in Japan. In addition to above-mentioned physico-chemical tests, NIR spectroscopy,“Midometer”and“Taste sensor”are novel and useful to evaluate eating quality and processing suitabolities. Recently, rice wholesalers and retailers have been obligated to display the name of cultivar, location of cultivation and the year of production of rice grains which they sell by the Japanese Agricultural Standard Law (JAS). In order to detect the dishonest labeling of rice cultivars, we developed new cultivar identification method based on DNA polymorphism.