• Applied Biological Chemistry
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• v.40 no.4
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• pp.313-317
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• 1997

To assess the physiochemical characteristics of greenhouse Satsuma mandarin (Citrus unshiu Marc. var, miyakawa) produced in Cheju, were analyzed chemical compositions for fruits, external and internal factors influencing the edible quality. Changes in organoleptic value according to brix and acid content were also evaluated. The ratios of sucrose : glucose : fructose in citrus juice were 2 : 2 : 1.5. Citric acid as the main acid in the juice represented about 70% of total organic acid. Most of the amino acids were found to be nonessential amino acids. Deep yellow color of the citrus peel showed a significant relationship(r=0.563) with brix/acid ratio of the citrus juice, indicating the ripeness of the fruit. Since the acid content showed highly negative statistical relationship(r= -0.882) with the pH value of the juice, the pH value appears to be a simple indicator for the sourness of the fruit in the field test. The fruits were divided into 9 groups based on the brix/acid contents for sensory evaluation. The palatability patterns of each group changed depending on the acid content. The optimal ranges of brix/acid content for acceptable taste were 11 and $0.5{\sim}1.0$, respectively.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.243-248
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• 2013

This study was conducted to understand the settlement process of Ascotis selenaria larvae into citrus orchards with respect to oviposition site and analysis of the spatial distribution pattern of the larvae. A. selenaria eggs were not found on citrus trees in field and green house, but not on citrus trees in the field. A. selenaria larvae showed a significant clump distribution in the greenhouse. In the open citrus field, the index of dispersion was around 1.0 in most cases, with a weak clumping degree. However, the d-statistic was between -1.96 and 1.96, indicating a statistically significant random distribution. In addition, the Green's index (a clumping index) was very low in all cases, even though the clump distribution was accepted. for most samples, the probability distribution of larval frequency in the field satisfied the probability distribution functions of Poisson (random pattern) and the negative binomial (clump pattern) distribution. In addition, the temporal distribution of the larvae in the open field showed a pattern which was formed by colonizers from outside oviposition sites. Further, the difference in larval spatial distribution between field and greenhouse orchards was discussed.

• 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.