• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.387-390
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• 1989

Citrus fruit (Citrus unshiu Marc) were stored in the facillity controlled with a microprocessor-based storage controller, and the respiration rate and weight loss of fruits were measured with the infrared gas analyzer and the strain gauge load cell. The storage conditions and measuring intervals were set by the keyboard of personal computer. The interfacing cicuitry between the computer and Z-80 microprocerssor was built with peripheral Interfacing It chips 6821 and 8255. The data measured were saved to a data file for recording and further analysis. When the fresh and bruised fruits were subjected to the storage condition for 4 days at 20 C, the respiration rate of the fresh one showed a stable value of 3-5ml $CO_2/kg$ h throughout the storage period while the bruised one exihibited an abruptly increased rate after 50 hours. And the weight loss recorded about 5% during the storage.

• Food Science and Preservation
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• v.11 no.3
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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.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.313-317
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• 2012

BACKGROUND: Citrus is usually propagated by grafting onto a rootstock. In Korea, As trifoliate orange (Poncirus trifoliata) has dwarf and strong cold hardness, it is widely used as the rootstock of satsuma mandarin. Because 'Shiranuhi' ((Citrus unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulata), a kind of citrus, also, generally is grafted onto a trifoliate orange, most of farmer has been recognized that 'Shiranuhi' root is naturally trifoliate orange. Meanwhile, reduction of flowering in 'Shiranuhi' orchard has been issued among the farmers and researchers over past few years and they guessed it was occurred by severe prune, oversupply of fertilization, overfruiting and temperature of growth period. However, a few researchers strongly assumed that it would be caused by scion rooting of 'Shiranuhi'. So, this study was carried out to identify the existence of scion rooting in 'Shiranuhi' tree in Korea. METHODS AND RESULTS: To identify the existence of scion rooting in 'Shiranuhi' tree, we randomly selected six 'Shiranuhi'orchards and we surveyed three to four trees, which flowering was not enough, from six 'Shiranuhi' orchards respectively. We took the root samples of 'Shiranuhi' mandarin, and then separated the two group which were non-scion rooting (Trifoliate orange), and scion rooting ('Shiranuhi' mandarin). To identity the scion rooting, we used primer set of three types which were a F2/R15, F4/R15 and F5/R15 primer set. As a result, when we conducted the DNA analysis, fourteen tree in less bloomed twenty tree was proved as tree with the scion rooting of 'Shiranuhi' mandarin. CONCLUSION(S): Scion roots of 'Shiranuhi'mandarin were usually observed in a deeply planted tree, and xylem of 'Shiranuhi' root indicated more white color than a case of trifoliata orange. 'Shiranuhi' tree by scion rooting was more vigorous but less flowering than trees grafted onto trifoliata orange. When we used F2/R15, F4/R15 and F5/R15 primer set for discriminance of 'Shiranuhi'mandarin root and trifoliate root, we identified the existence of scion rooting in 'Shiranuhi', From our results, it is suggested that the influence of scion root should be reviewed in 'Shiranuhi'orchards.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.69-74
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• 2015

To analyze quantitatively environmental characteristics of cultivation area of citrus, Satsuma mandarin (Citrus unshiu Marc.), we made digital maps of environmental elements such as topography and climate. Elevation, degree of slope, and slope aspect were selected as elements of topological environment, and the annual mean air temperature, annual total precipitation, mean air temperature on January, extreme value of daily minimum air temperature, and the number of days below $-5^{\circ}C$ were selected as elements of climatic environments. The grid values of 8 environmental elements were extracted by shape of citrus farm area and analyzed distribution patterns. We can determine 3 agroclimatic criteria for growing Satsuma mandarin as over $14.5^{\circ}C$ of annual mean air temperature, over $-10.0^{\circ}C$ of extreme value of daily minimum air temperature, and less 5 days of below $-5^{\circ}C$ of daily minimum air temperature.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.577-582
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• 2011

Greenhouse satsuma mandarins (Citrus unshiu Marc., cv. Gungchun) of an early harvesting cultivar were treated by hot water showering at 65$^{\circ}C$ for 10 s at a commercial scale in a packing house and then stored at 5$^{\circ}C$ for 3 weeks and subsequently at 18$^{\circ}C$ for 1 week (simulated shelf-life) to examine the potential use of hot water treatment (HWT) as an environmentally benign method to maintain mandarin quality characteristics during postharvest storage and sale. The respiration rate just after heat treatment or during storage was at a similar level in both the treated and untreated fruit. HWT also had no detrimental effects on quality attributes including pH, titratable acidity, soluble solids content, weight loss, firmness, and peel color. The development of stem-end rot, mold decay, and black rot was lower in the heat-treated fruit compared to those in the untreated control. A sensory evaluation showed that HWT markedly improved fruit appearance, making the fruit cleaner and glossier. The results suggested that HWT can be applied to satsuma mandarin as an effective pretreatment to maintain postharvest quality during storage and marketing.

• Food Science and Preservation
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• v.9 no.1
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• pp.85-91
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• 2002

Quality changes of over-wintering satsuma mandarin (Citrus unshiu Marc. var. miyagawa) during storage by chitosan and calcium treatment and type of storage warehouse were investigated. Citrus were treated with 2000-folds diluted iminoctadime-triacetate solution and 1.5% chitosan with 0.5% CaCl$_2$ solutions and were at 30$\^{C}$ far 24 h before storage. The citrus of about 12 kg/26 L plastic container were stored at room temperature, and at 4$\^{C}$ with 87% relative humidity. Chitosan and CaCl$_2$ solution treated citrus fruits were showed lower in decay ratio than the ones without treatment. Also, these chitosan and calcium treated citrus fruits skewed less in weight loss, that seems it also has restraining effect of fruits' transpiration. Decay ratio of citrus with precise temperature and humidity control were lower than the others during storage. Weight loss, moisture content of peel and flesh were decreased slowly during storage. 0.84 ∼0.90% of acid content were decreased on 120 days' storage. Reducing sugar of citrus was decreased rapidly after 90 days, and vitamin C content were also decreased rapidly after 60 days during storage.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.306-312
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• 1998

Free sugar, organic acid, naringin, hesperidin and inorganic elements change of six varities of Cheju citrus fruits; Citrus natsudaidai, C. grandis, C. platymamma., C. sudachi, C. aurantiun and C. unshiu Marc. var. miyagawa by harvest date were investigated. Changes in free sugar of citrus fruits on the different harvesting stages and varieties showed a little differencies. The content of sucrose, glucose and maltose in citrus juice were $44.9{\sim}66.0%,\;15.7{\sim}25.7%\;and\;17.5{\sim}30.1%$, respectively. As the fruits were matured, free sugar was increased, but organic acid was decreased gradually. The major organic acids from the fruit juice were citric acid, malic acid and oxalic acid. Citric acid content exceeded 90%, oxalic acid ranged less than 3.58% and malic acid ranged $0.98{\sim}9.45%$ in total organic acids. Both naringin and hesperidin content showed markedly high in immature fruits, and in rind compare to fruit juice. Naringin and hesperidin content decreased as peel coloration progressed. It was estimated that fully matured fruits would be useful for making processed products, which lead to less turbity and less bitterness.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.33-38
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• 1993

In order to utilize Kumquats as a processed products, a Citrus varieties produced in Cheju island, physicochemical properties of Kumquats, sensory evaluation of frozen Kumquats, sensory evaluation and texture parameter of Kumquats processed foods were investigated. Fruit size, weight, peel ratio, peel thickness, and Brix/acid ratio of Youngpa Kumquats cultivated in green house were 29.5 mm, 16.10g, 4.63 mm and 20.0 respectively, and it was suitable for as raw-eating and processing materials. Kumquats juice consisted of 58.27% citric acid, 32.49% malic acid, 9.14% tartaric acid and 0.08% maleic acid of total organic acids. Organic acid contents of Kumquats juice was very different from Citrus unshiu juice in malic acid content. Sensory evaluation on frozen Kumquats stored at $-18^{\circ}C$ for 6 month was good for appearance, taste and texture as summer commodity. Vitamin C content of frozen Kumquats was 74.94 mg/100g, and its content was decreased slightly during fronzen storage. Hardness on Kumquats jam was lowered from 1,294 to 355 g-force as the ratio of Kumquats juice content was increased, but the changes of other texture parameter were not so large. Kumquats jam contained $40{\sim}60%$ orange juice was evaluated as superior to orange jam for panelists.

• Food Science and Preservation
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• v.8 no.2
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• pp.131-139
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• 2001

Kiyomi tangor(Citus unshiu x sinensis) was stored at 3$\^{C}$ and 85% relative humidity, and the changes in firmness, pectin degrading enzymes activity and other physicochemical properties of citrus fruits during storage were investigated. Decay ratio and weight loss during 180 days’ storage were increased gradually to 13.0% and 12.9%, respectively. Firmness of fruits with 2 mm probe was decreased gradually from 808.7 g-force to 406.4 g-force, and moisture of peel and flesh were decreased from 76.5% to from 89.6% to 87.6% during storage, respectively. Exo-polygalacturonase activity of peel after 150 days’ storage were increased gradually to 558.09 units/100g. Pectin methylesterase activity of peel and flesh were increased from 14.7 units/g to 2.3 units/g, and from 9.4 units/ml to 2.7 units/ml at 150days’ storage, respectively. Endo-polygalacturonase activities were not changed notably during storage. Alcohol-insoluble solid(AIS) of peel was not changed notably. During storage of the fruits water soluble pectin(WSP) of peel and flesh were increased from 474.49 mg/100g to 614.29mg/100g, and from 66.91mg/100g to 92.74mg/100g as wet basis, respectively. Hexameta-phosphate soluble pectin(HMP) of peel were decreased from 405.5mg/100g to 270.43mg/100g, hydochloric acid soluble pectin(HSP) of peel was also decreased from 544.02mg/100g to 412.64mg/100g during storage. Total pectin substance(TPS) of peel and flesh were decreased from 1,424.01mg/100g to 1,297.36mg/100g, and from 165.51mg/100g to 171.54mg/100g, respectively. Composition ratio of pectin was in order of WSP > HSP > HMP.

• Herbal Formula Science
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• v.28 no.4
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• pp.327-337
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• 2020

Objective : Citri Unshius Pericarpium is the dried peel of mature fruit of Citrus unshiu Markovich and has been used to treat indigestion, vomiting, and removal of phlegm. This study investigated the hepatoprotective and antioxidant effect of CEE (Ethanol extract of Citri Unshius Pericarpium) in cadmium (CdCl₂)-treated HepG2 cells. Methods : Component analysis of Citri Unshius Pericarpium was analyzed by UPLC with C₁₈ column. Cell viability was determined by MTT assay. The enzyme activity of superoxide dismutase (SOD) and the level of reactive oxygen species (ROS) and reduced glutathione (GSH) were analyzed using commercially available kits. Results : Cadmium caused severe HepG2 cell death. Cadmium also increased ROS production, consistent with depletion of GSH and inhibition of the SOD enzyme. However, CEE treatment reduced cell death and relieved oxidative stress caused by cadmium toxicity. CEE lowered ROS levels and improved depletion of GSH levels. CEE also enhanced the enzymatic activity of SOD. In component analysis, hesperidin was the most abundant of the five marker compounds (Narigenin, Narigin, Narirutin, Hesperidin and Hesperidin), which assumes that hesperidin partially contributed to the antioxidant activity of CEE. Conclusion : These results suggested that CEE could be a potential substance to solve heavy metal-related health problems. In particular, inhibition of oxidative stress by CEE can be a way to treat liver damage caused by cadmium.