• Food Science and Biotechnology
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• v.17 no.5
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• pp.1016-1020
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• 2008

Parameters of soluble solids, amino acids, catechins, and color difference of 24 green tea samples from China and Korea were determined. The levels of soluble solids, amino acids, total catechins, and infusion lightness in tea samples from Korea were higher than those from China. Concentrations of epigallocatechin galate and epigallocatechin in teas from China were higher than tea samples from Korea. Geographical origin of teas from the 2 countries was discriminated using parameters of infusion lightness, gallocatechin, and total catechins and applying principal component analysis.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1525-1525
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• 2001

Non-destructive determination of soluble solids(Brix) in harvested fruits using near infrared(hereafter, NIR) spectroscopy has been reported by many researchers. We have just reported on non-destructive estimation of Brix in harvested melons using a NIR Systems Model 6500 spectrophotometer(Ito et al., 2000). There is a melon cultivar that is difficult to judge the harvest time from the external appearance. If we can determine Brix in growing fruits non-destructively in the field, immature fruits will not be harvested. A portable m spectrophotometer for field use has been just developed by Kubota Corporation. The spectral data of growing melons were measured by the portable spectrophotometer. A commercial program was used for multiple linear regression analysis. Brix in growing melons could be estimated by a multiple regression equation calibrated with harvested melons. Absorbances of 906 and 874 nm were included as the independent variables in the multiple regression equation, and these wavelengths are key wavelengths for non-destructive Brix determination.

• Food Science and Preservation
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• v.5 no.1
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• pp.1-6
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• 1998

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.

• Food Science and Preservation
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• v.5 no.1
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• pp.41-47
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• 1998

Physicochemical properties and microbiological quality chanties were investigated on mixed fruit and vegetable juices (apple, carrot and cucumber) stored at 4$^{\circ}C$ without pasteurization(NT), with light piasteurization (LP; 66$^{\circ}C$, 10 sec) and with full pasteurization(FP; 90$^{\circ}C$, 60 sec). Effects of ultrafiltration (UF) on the changes during storage were also examined. pH, viscosity, a-value and b-value remained relatively constant and all samples revealed Newtonian characterisitics. Total acidity and turbidity tended to increase slightly; however, total vitamin C content and L-value slowly decreased during storage up to about 2 months. During the first 4 weeks storage, soluble solids content slowly increased and then decreased. Mold and Yeast and Bacteria were not detected in LP, UP and UF treated samples during storage studied; however, E. coli were detected after 24 days storage. No distinctive storage effects were found among samples prepared; however, ultrafiltration had a considerable effect on the color and soluble solids content of mixed fruit and vegetable juice.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.62-64
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• 1969

The experiment was carried out to investigate the adaptability of freezing process with thirteen strawberry varieties cultivated in Suwon, Pusan and Chunju area. Six of these were local varieties and the others were varieties imported from the United States of America. Each strawberries variety was analysed chemically to determine value of soluble solids, acidity (calculated as citric acid) and deepness of color. Frozen products were prepared by a general method adding sugar to $28^{\circ}\;Brix$. Local varieties Haengok, Bokuh, Keikwan and Daehak No. 1 were not suitable for making into frozen products because of excessive white color in their centers. Blakemore, an imported variety, was best as to color. Chemical analysis showed that imported varieties have higher acidity, and lower content of soluble solids. In a sensory test conducted by fifteen members of Agriculture and Fishery Development Corporation, deeper colors of strawberries did not receive a generally favorable response, and it was found that strawberry colors favored by the America were not liked by Korean well.

• Food Science and Preservation
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• v.7 no.1
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• pp.51-56
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• 2000

Quality characteristics of Satsuma mandarin (Citrus unshiu Marc.var.miyagawa) harvest on early December according to production areas and sea level altitude of Cheju were investigated. Soluble solids and flesh ratio were distributed 9.32∼12.50, 75.95%-81.3 in citrus fruits harvested in orchards located below 10m sea level altitude (lower area), and was 10.23-12.17 , 77.35%-80.29% on those over 150m sea level altitude )higher area), respectively. Acid content of citrus juice was 0.95%-1.26% in fruits harvested inlower area, and was 1.02%-1.39% in higher area. In proportion to late harvesting , Brix/acid ratio and fruits quality was improved. Soluble solids of fruits harvested in higher area were higher than those of fruits from higher area, but acid contents were on the contrary . In sensory evaluation on fruit appearance, the differences between two altitudes were not clear.

• Food Science and Preservation
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• v.4 no.2
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• pp.131-137
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• 1997

Effect of storage on the tree and quality of early cultivar of Citrus unshiu Marc. produced in Cheju according to harvest time were investigated. Soluble solids, acid content, flesh ratio, firmness and specific cavity of the fruits harvested at 27th of November were 12.0, 1.03%, 79.98%, 0.774kg-force, 0.912, respectively. Soluble solids, total sugar and reducing sugar were increased gradually, but acid content was decreased slightly as delayed in harvest time. Otherwise specific gravity and firmness were not shown in great during harvest time, color index(a/b) was increased sharply till late November and then remained in stationary phase. On these result, we recommend that the harvest time of early cultivar of Citrus unshiu Marc. would be during December because of wilting partly. Fully ripened-fruits harvested late, compared to ordinary harvest time, with cold storage would be kept more quality and freshness of fruits for fresh consumption than the fruits harvested early and stored at room temperature.

• Food Science and Preservation
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• v.2 no.1
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• pp.139-146
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• 1995

Soluble solids and total carbohydrates of Citrus miyakawa wase harvested middle of November 1993 Topyung-Dong, Seogwipo-si, and Cheju were 10.7 and 8.57%, and carbohydrate was consisted of about 1/2 sucrose, 1/4 glucose and 1/4 fructose, respectively. Acid content of citrus Juice was 1.04%, and citric acid was 74.27% of total organic acids. Fruit weight, peel thickness, soluble solids, pH, hardness and edible part ratio had a good correlation in linear function with increasing fruit size. Total carbohydrate, reducing sugar and vitamin C of citrus jam made on optimum conditions were 65.33%, 27.98%, and 51.40mg/100g , respectively. Microbial growth on the products were not recognized at 3$0^{\circ}C$ for a month. Compared with other related citrus jellying products, the test sample was excellent in appear ance, taste and total preference degree on sensory evaluation.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.185-189
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• 2007

Quality characteristics of kochujang prepared with strawberry puree (10, 20, and 30% on the total weight basis) were investigated after 30 and 300 days of storage. The moisture content of strawberry kochujang at 300 days was considerably higher than that of strawberry kochujang at 30 days and increasing strawberry content from 0 to 30% significantly increased moisture content of kochujang progressively (p<0.05). Water activity and titratable acidity also showed similar trends, but pH showed the reverse trend with the highest value in control at 30 days and the lowest value in 30% strawberry kochujang at 300 days. As the strawberry puree content increased, amino-nitrogen content consistently and correspondingly decreased. Amino-nitrogen content at 300 days was higher than that of strawberry kochujang at 30 days. Soluble solids content also showed a similar trend, but soluble solid content at 300 days was considerably lower than that of strawberry kochujang at 30 days. Reduction in soluble solids content with increasing strawberry concentration was more evident at 30 days than at 300 day.

• Food Science and Preservation
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• v.4 no.1
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• pp.53-59
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• 1997

Physicochemical properties affecting on the quality of Citrus unshiu Marc. var miyagawa and C. unshiu Marc. var, okitsu according to cultivation area in Cheju were investigated. Linear correlations (r>0.9) were showed between fruit size and peel thickness. There were much difference between cultivation areas in soluble solids of C. unshiu Marc. var. okitsu. The difference were not so much in soluble solids and acid contents of citrus fruits produced at same area below 65mm of fruit diameter, but the quality of large size fruits were inferior. Brix/Acid ratio could not be index for quality evaluation, because of individual deviation. Soluble solid content of citrus fruits produced in south Cheju was higher than that produced in north Cheju. Acid content and Brix/Acid ratio of citrus fruits produced in south Cheju was lower than that produced in north Cheju. The quality of C. unshiu Marc. var. miyagawa clad not so much difference between cultivation area, but the difference of quality were recognized significantly in C. unshiu Marc. var. okitsu.