• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.247-257
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• 2010

The purpose of this study was to investigate the quality characteristics of Gamgyul-Injeulmi with different ratios of Citrus mandarin powder(0, 3, 6, 9, 12%) during storage. The moisture contents of the Gamgyul-Injeulmi decreased during storage but the moisture content of control(containing 0% Citrus mandarin powder) was almost constant. According to amylograms, gelatinization temperatures were lower in the samples containing Citrus mandarin powder compared to the control. More additions of Citrus mandarin powder caused lower viscosity and breakdown values but higher setback values. The pH of all samples decreased during storage but as more Citrus mandarin powder was added the changes in pH were less. The titratable acidity of all samples increased during storage and more additions of Citrus mandarin powder resulted in higher titratable acidity. For the Hunter's color values during storage, L and a values decreased but b values was increased except for the control. Textural analyses of the Gamgyul-Injeulmi showed that hardness, gumminess and chewiness increased, whereas adhesiveness, cohesiveness and springiness decreased during storage.

• Journal of the Korean Wood Science and Technology
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• v.51 no.2
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• pp.98-108
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• 2023

In this study, the boards were manufactured according to the mandarin peels addition rate using sawdust and mandarin orange peel. After that, the mechanical properties and density profile of ceramics prepared by conditions through resin impregnation process and carbonization process were investigated. The bending and compression strengths of ceramics tended to increase as the resin impregnation rate increased. When the resin impregnation rate was 70%, the highest values were 8.58 MPa and 14.77 MPa, respectively. Also, the mechanical properties of ceramics according to carbonization temperature showed the highest values at 1,200℃ for bending strength of 11.09 MPa and compression strength of 17.20 MPa. The bending strength and compression strength according to the mandarin peels addition rate showed the highest values at 8.62 MPa and 14.16 MPa, respectively, when the mandarin orange peel addition rate was 5%. The mechanical properties tended to decrease when the addition rate of mandarin orange was increased. The density profile of ceramics showed a similar tendency to the mechanical properties. It can be seen that the density distribution from the surface layer to the center layer is more uniform as the resin impregnation rate and carbonization temperature increase and the mandarin peels addition rate decreases.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.346-354
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• 1987

The voflatile fraction from Korean mandarin (Citrus reticula) and valencia orange essence oil were analyzed by capillary gas chromatography and the separated components were identified from their retention time and mass pectrum. The essence oil were extracted with methylene chloride after steam distillation. The major volatile constituents of mandarin and sweet orange was limonene which accounted for 68% of total volatiles in mandarin and 87% in sweet orange. The 31 components identified from mandarin include 11 hydrocarbones, 1 ester, 10 alcohols, 4 aldehydes, 5 miscellaneous. The following 37 components were identified in sweet orange; 12 hydrocarbones, 1 ester, 11 alcohols, 8 aldehydes, 5 misecellaneous. Mandarin contained more octanal, ${\alpha}-terpinene$, terpineol, styrene, dcitronellol, citronellal, citral and farnesol while orange included more sweet orange, myrcene, ${\beta}-pinene$, linallol, decanol, ${\beta}-copaene$, elemene, ${\beta}-cadinene$, valencene.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.338-345
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• 1987

The Physicochemical properties of six varieties of domestic orange and orange juices which were grown and produced in Korea, were analyzed their qualities, including taste evaluation based on the amount and the ratio of sugar and acid The physicochemical properties of mandarin were as follows soluble solid $10{\sim}11^{\circ}$ Bx, total acidity $0.76{\sim}1.20%$ ratio of sugar and acid $7.9{\sim}13.8$. Sugars of orange are mainly composed of sucrose, glucose, fructose. The sucrose content of mandarin was a little higher than that of sweet orange. The organic acids in orange were mainly citrate and malate. The content of these two acid in oranges were 0.8-1.4%. Mandarin type oranges tastes more sour than sweet orange. Hesperdin existed 30.8-67.5mg% in oranges. Naringin, one of the bitter components. was not detected in both varieties. The optimum sweetness and acid content were determined based on the results of sensory evaluation.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.525-529
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• 2013

As most of citrus, shiranuhi mandarin ((Citrus unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulata) mainly use the trifoliate orange (Poncirus trifoliata) as its rootstock which has dwarf and cold hardness in Korea. However, recently, scion root was observed in 'Shiranuhi' mandarin tree grafted onto the trifoliate orange. This study was carried out to find out effects of scion root occurrence on the fruit quality, flowering and yield of shiranuhi mandarin. For the experiment, we selected six farmers who have outbreak of scion root in their Shiranuhi mandarin orchards and surveyed the difference of fruit quality of shiranuhi mandarin hybrid between scion root and control (trifoliate orange root). In the results, flowering was severely decreased in scion root trees compared to control. As a result of survey of 174 Shiranuhi mandarins, 160 trees were proved to be scion root, and had less flowering. Fruiting of scion root also severely dropped compared to control and thus, yields of scion root (6.4 kg) reduced by 24% compared to control (26.7 kg). The fruit size, weight and soluble solid contents of scion root were significantly reduced, but there were no differences in acid contents and coloring of fruit. From the results, we concluded that scion root had negative influence on flowering, fruit size and the yields of Shrinanuhi mandarin hybrid.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.314-320
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• 2019

BACKGROUND: As consumption of unripe mandarin increases, its cultivation has increased in open field cultivation areas. Because unripe mandarin must be harvested before ripening and color change, the optimum harvest time must be determined. This study investigated the effect of the harvest season on the yield of unripe fruit and biennial flowering of 'Miyagawa' satsuma mandarin. METHODS AND RESULTS: Two areas of unripe mandarin orchard were selected, and the yield, fruit growth, working time, and flowering of trees the following year were investigated. Fruit was harvested at 40, 60, 80, 100, and 120 days after full bloom and at general ripening. Fruit yield of unripe mandarin increased with later harvest time from 100^th to 120^th day except normal ripening. The next year, biennial occurred with normal ripening and harvesting, but not at the 120^th day after full bloom. At the 40^th day (earliest harvest time), summer and autumn shoots were present, but not after the 100^th day. The 40^th day required the most harvesting time; because the time gradually decreased with later harvest, the harvest time was shortest on the 120^th day, and general ripening occurred shortly after the 120^th day. CONCLUSION: Harvesting of unripe mandarin 100-120 days after full bloom was ideal to reduce harvesting time, enhance yield, and enable flowering the following year.

• Phonetics and Speech Sciences
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• v.12 no.1
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• pp.11-17
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• 2020

Non-tonal language speakers may have difficulty learning second language lexical tones. In the present study, we explored this issue with Korean-speaking learners of Mandarin Chinese (i.e., non-tonal first language speakers) by examining their perception and production of Mandarin lexical tones. In the perception experiment, the Korean learners were asked to listen to the tone of each stimulus and assign it to one of four Mandarin lexical tones using the response keys; in the production experiment, the learners provided speech production data for the lexical tones and then their productions were identified by native listeners of Mandarin Chinese. Our results showed that the Korean learners of Mandarin Chinese had difficulty in perceptually distinguishing Tone 2 and Tone 3, with the most frequent production error being the mispronunciation of Tone 3 as Tone 2. We also investigated whether unfamiliar non-native phonemes (i.e., Chinese phonemes) that do not exist in the native language phonemic inventory (i.e., Korean) may hinder the processing of the non-native lexical tones. We found no evidence for such effects, neither for the perception nor for the production of the tones.

• The Plant Pathology Journal
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• v.15 no.4
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• pp.236-241
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• 1999

Sclerotinia twig blight on trees and cottony rot on fruits of Satsuma mandarin were observed in Cheju, Korea in 1996 and 1997. The causal fungus causing citrus twig blight and cottony rot was identified as Sclerotinia sclerotiorum which had cup-shaped apothecia bearing hyaline and clavate asci and periphyses on sclerotium. Symptoms were produced on twigs, developing young leaves, fully developed new leaves, and fruits 2-9 days after wound inoculation, but only on twigs with young lateral buds and developing young leaves by unwound inoculation. The fungus grew well between 10 and $27^{\circ}$, but optimum temperature was $24^{\circ}$ on potato dextrose agar. Most varieties were highly susceptible to S. sclerotiorum, whereas some varieties such as Ichinan were relatively resistant among twelve Satsuma mandarin varieties in the field. This is the first record of Scledrotinia twig blight on trees and cottony rot on stored fruits of Satsuma mandarin in Korea.

• Journal of the Korean Wood Science and Technology
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• v.47 no.1
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• pp.66-79
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• 2019

The aim of the study is to use the by-products sawdust, formed during sawing and mandarin peel which are agricultural by products. The boards were manufactured by mixing the sawdust and mandarin peel at different mixing ratio and density. In terms of changes in surface temperature of ceramics, we could found that the velocity was fast in the early time of heat transfer until 10 minutes and after that the velocity increased but not very fast. At the elapsed time of 30 minutes, the surface temperature of ceramics increased with the carbonization temperature and rate of mandarin peel addition did not influence the surface temperature. Far - infrared emissivity had no constant tendency in rate of mandarin peel addition, it decreased with increase of carbonization temperature.

• Journal of Food Hygiene and Safety
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• v.37 no.5
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• pp.356-363
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• 2022

To investigate the functional activity of different citrus fruit peels, antioxidant compounds in 70% ethanol extracts of mandarin, lemon, orange, and grapefruit peel powders were identified, and antioxidant and antibacterial activities were quantitated. Mandarin peel contained the highest content of total phenolic compounds and total flavonoid substances (21.46±0.12 mg GAE/g and 11.57±0.05 mg RE/g, respectively). The total phenolic compound content of the three other citrus fruits was 14.16±0.18-18.44±0.07, and their total flavonoid content was 5.51±0.10-7.46±0.09 mg RE/g. DPPH radical scavenging activity was the highest in lemon peel (87.64±0.21%), and mandarin peel displayed the best antioxidant activity with respective ABTS radical scavenging activity and FRAP measurements of 43.20±0.61% and 78.82±1.06 mM TE/g. Grapefruit peel antimicrobial activity increased with treatment time, and was the most potent among the four tested citrus species, inhibiting Staphylococcus aureus by about 4.05 log cycle. These findings demonstrate that mandarin and grapefruit peel can be used to prevent oxidation, improve food storage capabilities, and potentially preserve food quality.