Carotenoids are major secondary compounds in Citrus determining the color of fruit and nutritional values. Carotenoids are isoprenoic compounds, and function as color pigments in the flower and fruit to attract pollinators and seed-dispersing animal and chromophore for light harvest and photoprotectant during photosynthesis. In the aim of developing new cultivars with high value using molecular breeding technology, we had performed screening of flesh and peel specific genes by differentially expressed gene screening in Citrus unshiu fruits. From the screening, carotenoid isomerase (CRTISO)1, which converts pro-lycopene to all-trans-lycopene, was identified as peel-specifically expressed gene. In this study, the gene encoding the CRTISO1 was cloned, sequenced, and compared to the CRTISOs in other plant species. Comparison of the cds sequence to other plant species revealed 75% and 78% identity with CRTISO1 of Zea maize and CRTISO2 of Arabidopsis thaliana respectively. We also cloned CRTISO2 from C. unshiu which declines the expression while maturation (Kato et al., 2004), and the gene structure was analyzed. This is the first work reporting the full sequence and gene structure of CRTISOs in C. unshiu, and would give important information in understanding the carotenoid synthesis in the Citrus fruit.

This study was conducted to determine the effects of the humidity and gas composition on the quality of satsuma mandarins during their heat treatment, in an effort to reduce their acidity. To come up with different humidity and gas conditions, various plastic films were used. The fruits were wrapped with an 18-μm high-density polyethylene (HDPE) punched film, a 30-μm low-density polyethylene (LDPE) film, or a 100-μm LDPE film just before treatment at 30℃ for 55 hours. After heat treatment, the titratible acidity (TA) was significantly reduced while the soluble-solid content (SSC) showed no differences, which resulted in increased SSC/TA ratios in all the treatments. The fruits that were not wrapped with a film, however, which had low RH, developed higher ethanol and acetaldehyde contents than those wrapped with an 18-μm HDPE punched film, which had high RH and a similar gas composition. Among the films, the higher the CO2 concentration in the film was, the more the ethanol and acetaldehyde contents increased, which induced more off-flavor. It was thus concluded that high humidity and normal gas composition are favorable conditions for heat treatment to reduce the acidity of satsuma mandarins.

A new early maturing satsuma mandarin (Citrus unshiu Marc.) ‘'Haryejosaeng’' was developed as a nucellar seedling selection of ‘'Tachima Wase’' (C. unshiu Marc.) that was crossed with C. natsudaidai Hayata at the National Institute of Subtropical Agriculture in Jeju island in 1992. The ‘'Jegam ga No. 2’', a first selection from the seedlings fruited in 2001 was finally named “"Haryejosaeng”" through field evaluation trials at three locations in Jeju island from 2003 to 2004. ‘'Haryejosaeng’' produces seedless fruit maturing in early November, and has higher soluble solids and lower acidity than ‘'Miyagawa Wase’', the leading early-maturing satsuma mandarin cultivar in Jeju island. Fruit weight is moderate at about 80～90 g and its shape is compressed-oblate globose with a light orange color. The rind thickness of about 2 mm provides easy peeling. The flesh shows light orange colored and contains 10 to 11 Brix and 1 to 1.1% acidity when mature. Tree shows vigorous growth and spreading thornless twigs. Alternate bearing is similar to ‘iyagawa Wase’ ‘aryejosaeng’is susceptible to citrus scab disease and melanose, but resistant to citrus canker.

감귤의 수확 후 저장, 유통과정에서 부패 억제 및 품질유지 효과를 얻기 위하여 환경친화적 방법으로서 중-고온 예조처리의 적용 가능성을 확인하고자, 조생종 온주 감귤의 열풍처리에 따른 저장 중 품질특성 변화를 살펴보았다. 45에서 2, 4, 6시간 동안 열풍을 가한 다음, 충분히 냉각시킨 감귤을 통기성 천공 LDPE 필름에 포장하여 5에서 3주, 18에서 1주간저장하면서 호흡률, 과실내부 기체조성,pH, 산도, 가용성 고형분 함량, 과피 표면색,

저장고 형태에 따른 온주밀감의 저장 중 품질특성을 검토하였다. 항균제로서 베프란(iminoctadime-triacetate) 2,000배 희석액과 키토산 1.5%에 0.5% CaCl를 혼합한 용액에 감귤을 충분히 침지 하였다. 풍건시킨 후 26L인 플라스틱 컨테이너에 감귤을 12kg 정도씩 담아 3에서 24시간동안 저장전처리를 하고, 상온저장과 내부온도 4 상대습도 87%를 기준으로 저장하였다. 저장고내의 온습도 편차가 적은 저장고에서 가장 낮은

저장고 형태에 따른 온주밀감의 저장 중 품질특성을 검토하였다. 항균제로서 베프란(iminoctadime-triacetate) 2,000배 희석액, 키토산 1.5%에 0.5% CaCl를 혼합한 용액에 감귤을 충분히 침지하였다. 풍건시킨 후 26 L인 플라스틱 컨테이너에 감귤을 12 kg 정도씩 담아 3에서 24시간동안 저장전 처리를 하고, 상온저장과 내부온도 4, 상대습도 87%를 기준으로 저장하였다. CaCl를 함유한 키토산 용액을 처리한 감귤이

감귤의 저장 중 손실율을 줄이고 신선도를 유지하기 위하여 베프란, 키토산과 CaCl을 처리하고 상온저장과 4, 873%의 조건에서 저장하면서 궁천조생 온주밀감의 품질변화를 검토하였다 온주밀감의 저장기간 중 부패율은 2월 중순부터 상온 및 저온저장에서 무처리에 비하여 2000배 희석한 베프란 용액, 0.5% CaCl를 함유한 1.5% 키토산 용액을 처리한 감귤이 부패과 발생이 매우 낮았다. 또한, 키토산과 CaCl을 처리한 감귤에서 중량감소도 적게

Physicochemical properties and sensory evaluation of Satsuma mandarin produced in Cheju were investigated . Fruit index(width/Length), soluble solids and acid content of Citrus unshiu marc. var. miyagawa(miyagawa) and C. unshiu marc. var.(okitsu) harvested at 1st December were 1.16 and 1.23, 12.12 and 12.01, 0.97 and 1.09, respectively. and the fruit of miyagawa was showed somewhat round in shape, compared to ikitsu. the taste of miyagawa seemed to be better than okitsu. However, compared to miyagawa, peel thickness was thinner, flesh ratio was higher, and firmness was higher as 0.502kg-force in kitsu. Nevertheless there were some differences among panelist groups in sensory evaluation , middle size of citrus fruits were favorable to most panelists, but except very small or very large size of fruits, there were not so much differences in okitsu. The panelists referred to somewhat flat-shaped fruits from that sensory evaluation score was increased to 1.3 in fruit index. nevertheless there were not so much differences in full-colored fruits, the citrus peel color of reddish yellow was more favorable than greenish or pale yellow color. the score was increased more linearly according to citrusfruit produced in optimum ciltivation area, and was prefered to thinner in peel thickness , Correlation between soluble solids, acid content , Brix/acid ratio and flesh ratio with sensory evaluation score were not showed significantly, it was different to with citrus juice. This data obtained in this experiments are supposed to be applied to the quality evaluation of Satsuma mandarin produced in Cheju .

Changes in firmness and pectin contents during maturation and sotrage of Stsuma mandarin (Citrus Unshiu Marc. var. miyagawa) were investigated. Firmness of fruits was decreased quickly from 1,176.8g-force to 503.6g-dorce. Satsuma mandarin was stored at 3 and 85%5% relative humidity. Firmness were decreased from 538.9g-force to 336.9g-force during storage. Alcohol-insoluble solid(AIS) of peel and flesh were decreased quickly from 27.04g/100g to 12.30g/100g, and from 2.67g/100g to 1.91g/100g during maturation of fruits. During storage of fruits, AIS of peel was decreased from 14.32g/100g to 12.06g/100g . During maturation of fruits, water soluble pectin (WSP) of peel were increased from 420.82mg/100g to 601.62mg/100g as wet basis. Hexametaphosphate soluble pectin (HMP) was also increased from 450.17mg/100g to 577/53mg/100g. hydrochloricacid soluble pectin (HSP) was decreased from 1938.30 mg/100g to 695.14mg/100g. During storage of fruits, HMP and HSP of peel was decreased from 507.82mg/100g to 695.14mg/100g. During storage of fruits, HMP and HSP of peel was decreased from 527.82mg/100g to 275.47mg/100g , and from 672.28mg/100g to 351.36mg/100g, respectively. WSP of peel was increased from 543.70mg/100g to 584.31mg/100g. Total pectin substance (TPS) of peel was decreased from 2809.79 mg/100g to 1874.29mg/100g during maturation, and from 1723.80mg/100g to 1211.14mg/100g during storage, respectively. Composition ratio of pectin was in order of WSP>HSP>HMP.

제주산 감귤의 유통방법에 따른 선도 변화를 조사하고 저온유통의 효과를 검토하였다. 유통 중 성분변화는 상온(17)유통이 저온(5)유통에 비해서 중량감소는 6% 증가, vitamin C는 1.91mg 감소, 당산비는 20% 증가함을 보였다. 상온유통에서 중량감소로 인하여 당산비가 높아져서 (16.11에서 21.75) 감귤의 맛과 선도가 감소된다. 현행 감귤수송은 상온유통을 하고 있으나 고품질 감귤에는 부적합한 것으로 나타나며 고품질 소량생산 지향의

The stowage effects of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) were investigated by selecting various pretreatmnents; non-tested, wax-coating, paper packaging, 0.02mm cryovac film packaging. Weight loss of film packaging was the lowest among that of others, but decay radio was increased highly at late stages of storage. Soluble solids, moisture content of peel and total sugar were maintained almost constant, but acid content, vitamin C and firmness were reduced gradually during storage at room temperature. For 100 days storage, losses from weight and decay of ton-treated, paper packaging, wax-coating and film packaging were 15.9%, 18.5%, 17.4% and 12.9%, respectively. Acid content was decreased loom 1.28% to 0.81∼0.91% after 100 days storage. Ethylene evolution was increased in a degree after 65 days storage, and the amount was increased repidly afer 115 days. it seemed to be derived from decayed fruits and physiological activities. CO2 content of inner part of fruits was increased between 40∼100 days after storage. Optimum storage period of early variety of Satuma mandarin was regarded for 100days on the basis of appeareance and taste.

Physicochemical properties of early cultivar of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) according to harvesting year during 1990 to 1995 were investigated. Climatic conditions of every year affected the quality of citrus fruits. Compared to other harvesting years, flesh ratio and soluble solids were higher, but acid content was lower on citrus fruits produced in 1994, as for good climatic conditions during growth of fruits. Especially, acid content of fruits produced in 1993 was higher, compared to those of years, as for low mean temperature and high rainfalls. Fruit weight, peel thickness and soluble solids had a good linear correlation to fruits size, but acid content and flesh ratio had not correlation derived from difference of individual fruits. From the climatic data, the prediction of fruit quality would be possible in some degree before harvest. It seemed recommend to ably the flexibe method by harvesting year for the quality stanardization of citrus fruit.