초록 ▼

○ 연구결과
양파의 저장 장해별 유형을 구분하였고,저장 온도와 맹아엽 신장,동해와의 상관관계,이산화탄소의 농도와 투명인엽 현상의 발생의 상관관계를 파악하여 이로 인한 저장 장해를 억제하기 위한 최적 저장 환경을 구명을 하였다.또한,기존 수확후 관리 기술인 큐어링 관련 실험을 통하여 온도 조건을 개선하였고,이산화염소 가스를 양파에 처리하여 양파 저장을 위한 수확후 관리 기술의 응용의 폭을 확대하였다.
마늘은 저장 온도와 마늘 녹변과의 상관관계를 파악하여 마늘 저장 요건이 마늘의 녹변에 주는 영향을 파악하고,저장 요건에 따른

○ 연구결과
양파의 저장 장해별 유형을 구분하였고,저장 온도와 맹아엽 신장,동해와의 상관관계,이산화탄소의 농도와 투명인엽 현상의 발생의 상관관계를 파악하여 이로 인한 저장 장해를 억제하기 위한 최적 저장 환경을 구명을 하였다.또한,기존 수확후 관리 기술인 큐어링 관련 실험을 통하여 온도 조건을 개선하였고,이산화염소 가스를 양파에 처리하여 양파 저장을 위한 수확후 관리 기술의 응용의 폭을 확대하였다.
마늘은 저장 온도와 마늘 녹변과의 상관관계를 파악하여 마늘 저장 요건이 마늘의 녹변에 주는 영향을 파악하고,저장 요건에 따른 마늘 녹변 후보 유전자의 활성을 파악하고,관련 유황화합물과 아미노산의 마늘 녹변에 있어서의 역할을 파악하여 마늘의 녹변과 관련한 마늘 녹변 기작을 밝혀내어 마늘 녹변에 대한 이해의 폭을 넓혔고,열처리와 유기산 처리,수확 후 마쇄 마늘 냉동 보장 등의 방법을 통하여 마늘 녹변 억제를 위한 최적 가공 기술의 개발하였고,녹변 마늘의 유해성 평가를 통하여 녹변 마늘의 상업적 이용 가능성을 높였다.

Abstract ▼

1. Investigation on postharvest disorders of onion bulbs during storage
In this study, patterns of loss and causes of physiological disorders in several varieties of onion bulbs (Allium cepa) at different storage temperatures were investigated. Quality tests were also conducted to confirm the rel

1. Investigation on postharvest disorders of onion bulbs during storage
In this study, patterns of loss and causes of physiological disorders in several varieties of onion bulbs (Allium cepa) at different storage temperatures were investigated. Quality tests were also conducted to confirm the relationship between varieties and storage temperatures. Onion varieties such as 'Daego', 'Turbo', and 'Sunpower' were stored at -1, 0, 20℃ for 5 months to investigate physiological disorders during storage and at 0 and 20℃ for 5 months to evaluate quality changes in onion bulbs. Sprouted onions were found in onion bulbs stored at 20℃ and freezed ones at -1℃. Diseases, such as soft rot caused by Erwinia, basal rot by Fusarium, neck rot by Botrytis, and black mold by Aspergillus, were also founded during storage. Soft rot was the most usual disease in onion bulbs stored at -1 and 0℃ and molds were the most prosperous in onion bulbs stored at 20℃. However, one of physiological disorders, translucent scale, was not found during storage at any temperature. In quality tests, hardness was significantly decreased in onion bulbs stored at 20℃ than onion bulbs at 0℃ and accelerated disease development.
2. Improvement of postharvest handling in storage of onion bulbs
The effect of heated air vent, storage temperature, and high concentration of CO₂ gas on onion bulbs were investigated and pathogen of soft rot was isolated. Forced heated air vent was conducted on onion bulbs at 30℃ for 8 days and 40℃ for 4 days under the 60% relative umidity, and then onion bulbs were stored at 5℃ for 6 months. Storage of onion bulbs at 0, 5, 10, 15, and 20℃ was also conducted to elucidate the relationship between storability of onion bulbs and storage temperatures. To confirm the effect of CO₂ gas on onion bulbs, CA conditions (10, 20, 40, and 100% CO₂ gas, and 10, and 20% CO₂ gas with 6% O₂ gas) were applied to onion bulbs stored at 0℃ for 4 weeks. Sequencing of 16S rRNA and EF-TEM image analysis were conducted to elucidated pathogen of soft rot. Forced heated air vent reduced moisture content of onion skins and percentage of sprouted onion bulbs, and made deeper color. Under the temperature condition over 5℃, sprouted onion bulbs we e found after 5 months of storage and the most numerous sprouted onion bulbs were found at 10℃ after 7 months. None of onion bulbs exposed to any of the gas condition for 4 weeks showed translucent scale except for 100% CO₂ gas condition. The pathogen isolated from onion bulbs showing the symptom of soft rot was identified as Bacillus genus. In conclusion, forced heated air vent at relatively high temperature is an available method to reduce the moisture content of the outer surface of onion bulbs and storage of onion bulbs at 0℃ needs for long term of storage more than 5 months. With frequent ventilation and air circulation there are little chance of translucent scale caused by high concentration of CO₂ gas and the symptom of disease caused by Bacillus genus is quite similar with the symptom of soft rot.
3. Development of onion postharvest technology and program for onion storage
A sterilization method was developed for onion postharvest technology and a postharvest program for onion was designed. Chlorine dioxide (CD) gas was applied on onion bulbs (Allium cepa) to develop onion postharvest technology. CD gas was applied to unpeeled and peeled onion bulbs, and onion skins inoculated with microorganism at the concentration of 1000, 500, and 250 ppmv for 1, 05, and 0.25 hour, then samples were stored at 0℃ for 7 weeks. Reduction of the number of microorganism, visual appearance, weight loss, total soluble solids (TSS), pungency, firmness, total phenolic content, and antioxidant activity (ABTS) were measured. The postharvest program for onion was designed by adopting result of previous studies and research data. Application of CD gas reduced the number of microorganism inoculated on onion skins. No influence was caused by the application of CD gas in unpeeled onion bulbs, but numerous small sunken regions on the outer surface of onion bulbs, average more weight loss, and initial reducti n of total phenolic content and antioxidant activity were occurred by the application of CD gas in peeled onion bulbs. As onion bulbs without intact skins lose their marketability, CD gas is a disinfectant applicable for the storage of onion bulbs without any deleterious effect on the qualities of onion bulbs, and the postharvest program designed in this study would help reduce onion losses during storage.
4. Elucidation of the cause of greening in crushed garlic bulbs and synthesis of green pigment
Greening of crushed garlic bulbs occurs when garlic bulbs are stored at low temperature. Studies on the activities of candidate genes related to greening, g-glutamyl transpeptidase (GGT) and alliinase, in garlic bulbs stored at different temperatures and the color-forming ability of different amino acids with thiosulfinates in crushed garlic bulbs were conducted to elucidate the mechanism of greening in crushed garlic bulbs (Allium sativum). For the analysis of GGT activity, GGT sequence of garlic was partially cloned using an onion GGT sequence, and the relationships between garlic greening and related gene expressions depending on storage condition were investigated by using reverse transcription-polymerase chain reactions (RT-PCR) for GGT and alliinase of garlics stored at different temperature condition. Thiosulfinates were extracted from the crushed garlic and onion bulbs, and solution of extracted thiosulfinates and each one of 22 amino acids were incubated together at 60℃ for 3 h to confirm amino acids related to the greening of crushed garlic bulbs. As a result, the expression of the alliinase was unaffected by the storage condition, but GGT expression was changed with condition of storage temperature. As for the experiments on amino acids related to greening in crushed garlic bulbs, it was elucidated that the greening was created by the combination of yellow and more than eight blue pigments, and free amino acids forming blue pigments when reacted with thiosulfinates were glycine, arginine, lysine, serine, alanine, aspartic acid, histidine, asparagine, glutamine, and tyrosine. These results indicate that the greening in crushed garlic bulbs develops with increasing GGT expression at low temperature and the amino acids which would most likely be related with greening in crushed garlic bulbs are arginine, asparagine, and glutamine in the view of similarity of spectra with naturally-greened garlic extract.
5. The mechanism and suppression of greening in crushed garlic bulbs
The study was conducted to elucidated the mechanism of greening in crushed garlic bulbs and to develop methods for suppression the greening. The mechanism of greening were investigated through the model reactions performed with alliinase, glycine, ACSOs at different concentrations. Changes of storage temperature and application of organic acids were conducted to find methods to suppress greening in crushed garlic bulbs. In the model reactions, pink pigment was generated from 1-PeCSO, green pigment was generated with reaction of 1-PeCSO, 2-PeCSO, alliinase and amino acids. Therefore, 1-PeCSO was essential for the greening. Even non-greening garlic bulbs stored at 20℃ turned green by the addition of 2 % 1-PeCSO, thus 1-PeCSO isolated from onion bulbs had the same role with 1-PeCSO in greening of garlic bulbs. Onion bulbs turned green by the addition of 6% 2-PeCSO. The greening level of crushed garlic bulbs were different depending on cultivars, but the greening was appeared in all varieties of garlic at 0℃ after 3 months. Garlic greening was suppressed and content of 1-PeCSO were lowered in garlic bulbs when bulbs were transferred to 25℃ and stored for several weeks. While application of organic acids was also valid in suppressing greening, the greening of crushed garlic bulbs were not entirely suppressed and emitted sour smell. Therefore, greening of crushed garlic bulbs occurs due to increase of 1-PeCSO in garlic bulbs under low temperature and the transferring garlic bulbs to 25℃ and stored several weeks is the most suitable method to suppress garlic greening.
6. Safety evaluation of garlic greening and development in processing of crushed garlic bulb
Safety of garlic greening was evaluated and the optimal method for processing crushed garlic bulbs was developed. Safety of green crushed garlic bulb was evaluated by using mouse. The mouse was regularly fed with crushed non-greening garlic bulbs or greening crushed garlic bulbs for 28 days and damages on liver were estimated by the levels of AST, ALT, ALP, and GGT in the blood vessels. For the development of optimal method for processing crushed garlic bulbs, garlic bulbs were crushed after harvest and then stored at -10℃ for 5 months. And then, each crushed garlic bulbs was transferred to -10, 0, and 20℃ storage room and stored for aweek. Hunter 'a' value, sulfur compounds, and volatile compounds were measured. Levels of AST, ALT, ALP, and GGT in blood vessels of control mouse and mouse fed with crushed non-greening garlic or green garlic showed no difference. The garlic bulbs crushed after storage at 0℃ for 5 months showed greening after a day at room temperature. However, exposure of the crushed garlic bulbs to 20℃ condition made crushed garlic bulb de-greening. On the other hands, garlic bulbs crushed after harvest and stored at -10℃ for 5 months showed no greening for a week, whatever temperature condition those crushed garlic bulbs were transferred into, and also showed no greening even after a day at the room temperature, and the content of diallyl disulfide, one of the most important factors of garlic flavor, was not significantly affected by the process. In conclusion, crushed garlic bulbs and crushed garlic bulbs with greening are harmless, and the method crushing garlic bulbs after harvest and storing -10℃ is suitable for the processing of crushed garlic bulbs.

목차 Contents

• 표지 ... 1
• 제출문 ... 2
• 요약문 ... 3
• SUMMARY ... 7
• CONTENTS ... 12
• 목차 ... 13
• 제 1 장 연구개발과제의 개요 ... 14
• 제 1 절 연구개발의 필요성 ... 14
• 제 2 절 연구개발 목표 및 범위 ... 15
• 제 2 장 국내외 기술개발 현황 ... 19
• 제 1 절 국내 기술개발 현황 ... 19
• 제 2 절 국외 기술개발 현황 ... 20
• 제 3 장 연구개발수행 내용 및 결과 ... 23
• 제 1 절 양파 수확후 장해 유형 파악 및 장해발생 원인 구명 ... 23
• 제 2 절 양파의 수확후 취급과정 및 장해 방지 기술의 개선 ... 34
• 제 3 절 양파 수확후 관리기술 및 프로그램 개발 ... 45
• 제 4 절 마늘 변색 발생원인 구명 및 녹색 색소 합성 ... 62
• 제 5 절 마늘 변색 발생 기작 및 억제 ... 73
• 제 6 절 변색 마늘의 유해 여유 판정 및 가공 후 관리기술 ... 85
• 제 4 장 목표달성도 및 관련분야에의 기여도 ... 95
• 제 1 절 목표달성도 ... 95
• 제 2 절 관련분야에의 기여도 ... 97
• 제 5 장 연구개발 성과 및 성과활용 계획 ... 98
• 제 1 절 연구개발 성과 ... 98
• 제 6 장 연구개발과정에서 수집한 해외과학기술정보 ... 101
• (1) 양파 ... 101
• (2) 마늘 ... 101
• 제 7 장 참고문헌 ... 103
• 끝페이지 ... 106