• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.431-437
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• 2015

In this study, high-acidity cider vinegar (HACV) was produced by alcoholic and acetic acid fermentation of apple concentrate without any nutrients and then the optimum alcohol concentration was determined through a qualitative study. HACV was fermented with different initial alcohol concentrations (6-9%) during the process of acetic acid fermentation. The highest content of reducing sugar, organic acids, and free amino acids was observed at 6% of initial alcohol concentration. Approximately 20 types of volatile compounds were identified by solid-phase microextraction (SPME) and GC-MS. The total volatile content was the highest at 6% of initial alcohol concentration, and the acid content was the lowest at 9% of the initial alcohol concentration. The HACV produced by a two-stage fermentation process was qualitatively better than commercial HACV presenting the highest value at 6% of initial alcohol concentration. Malic acid, aspartic acid, and hexyl acetate were selected as quality index components of HACV production by two-stage fermentation on the basis of correlation between their physicochemical properties and the sensory attributes of HACV.

• Food Science and Preservation
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• v.17 no.3
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• pp.351-357
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• 2010

To decrease the intake of animal fat and cholesterol, changes in the physico-chemical characteristics of pork Boston butts cooked by different methods (boiling, steaming, baking, and frying) were investigated. Cooking weight loss and the drain rates of moisture, lipids, and cholesterol were highest during frying. The pH value increased during all cooking processes tested. The refractive index of meat fat increased markedly upon frying. The hardness, gumminess, and chewiness of meat were notably increased by frying. Springiness was not significantly affected by any cooking process, and cohesiveness was slightly increased by all cooking methods evaluated. The CIE $L^*$ (lightness) value was markedly increased upon steaming, and the CIE $a^*$ (redness) value decreased notably with boiling or steaming. The CIE $b^*$ (yellowness) value decreased slightly with either boiling or steaming, and was slightly increased when baking or frying was used. The fatty acid composition did not significantly change after cooking, except when meat was fried.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.79-89
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• 2005

Forest soils were analyzed on their biological and physicochemical properties for the ecological restoration of burnt forest soil using organic wastes and proper microorganisms. Three kinds of soil samples were collected from undamaged soil(US), naturally restoring soil(NS) and artificially restoring soil(AS). All soil samples were sandy soil and acidic soil, ranged pH 5.34~5.78. Moisture content was higher in the soil of NS region. And the others were similar. Total organic matter and soluble sugar were higher at the surface, generally. Heterotrophic soil microbes were abundant at the surface soil of NS and subsoil of AS. Dehydrogenase, cellulase and phosphatase activities were higher at the NS soil. Especially, Dehydrogenase activity as primary index of soil microbial process showed high correlationship with moisture content(r=0.90, P < 0.05).

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.602-607
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• 1993

These studies were conducted to investigates the changes in physicochemical characteristics of Charbori (waxy-barley) and Olbori (normal) during kernel maturation. 1000-kernel weight increased as the barley matured and as the original moisture decreased. The amount of total nitrogen per endosperm was similar in both cultivars. 1000-kernal weight had a correlation coefficient of $r=-0.871^{**}$ with water soluble nitrogen and of $r=-0.894^{**}$ with nitrogen solubility index. At maturity, the starch content of Olbori was 26% higher than Chalbori. Amylose content ranged from 20.4 to 24.7% in Olbori and from 9.9 to 12.9% in Chalbori as the kernel matured. ${\beta}-glucan$ viscosity was no differences at the early stages of development, but at 40 days after heading, was greatly differences between Chalbore and Olbori, 7.9 kand 5.8 cST, respectively. Gelatinization characteristics and other properties of the starch by Amylograph were compared with those of Olbori and Chalbori. The Chalbori starch usually had a lower initial temperature and setback.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.175-179
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were analyzed for their physicochemical charateristics and the compositions. Specific gravity, refractive index and yellowness of ERBO was higher than ARBO but smoking point was 60-$80^{\circ}C$ higher than ERBO. The free fatty acid content was 0.05% a ARBO and 0.88-1.36% ERBO. The wax was not detected in ARBO but the soft and hard waxes were detected in ERBO. The lipids were composed of 98-99% neutral lipid, 0.2-0.5% glycolipid and 0.1-0.5% of phospholipid in all samples. The triglyceride content of neutral lipid was 96.3% ARBO and 93.0-94.1% ERBO, and its monoglyceride content was 0.11% ARBO and 0.39-0.69% ERBO. The major fatty acid composition of samples were 41-42% oleic, 36-40% linoleic and 17-18% of palmitic acid.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.141-146
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• 1998

In order to determine the optimmum harvest time of Citrus unshiu Marc. var. miyagawa and C. unshiu Marc. var. okitsu produced in Cheju, citrus fruits sampled at packing houses or harvested directly on citrus tree in south and north area of Cheju were analyzed. The fruits were grown in size till middle of October, and soluble solids were increased continuously after that. The fruits size were different by positional directions on the tree, the quality of citrus fruits in central southern positions on the tree was good for fresh fruit consumptions. Compared with only the quality of citrus fruits as a factor of soluble solids, total sugar, pH, and color index, the optimum harvest time were supposed to be reasonable at late of November for C. unshiu Marc. var. okitsu, and at early of December for C. unshiu Marc. var. miyagawa. The results obtained from citrus fruits sampled at packing houses were supposed to be not suitable for determing the optimum harvest time, because of storage after harvest at ordinary harvesting time.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.463-468
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• 2017

Waxy rice starch purified from Hwaseonchal white rice was modified by octenyl succinic anhydride (OSA) for use as an emulsifier. OSA-modified starches (1, 2, and 3% OSA, pH 8.5, 6 h) were investigated to understand their physicochemical and pasting properties, and emulsion stability. The degree of substitution (DS) of 1, 2, and 3% OSA starches was 0.0062, 0.0182, and 0.0214, respectively. FT-IR spectroscopy showed that OSA starches showed weak peaks at 1724 and $1572cm^{-1}$ and the peak at $3300cm^{-1}$ was reduced by an increase in the DS. Native and OSA starches showed A type crystallinity and a similar granular size. The OSA starch increased the peak viscosity, but decreased the onset and peak temperatures, and enthalpy with an increase in OSA concentration. The creaming index of emulsion of OSA starches decreased with an increase OSA concentration. It was suggested that the emulsion stabilizing capacity of OSA waxy rice starches increased with an increase in the OSA concentrations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.798-804
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• 2008

The physicochemical properties of carrot beverage fermented by Leuconstoc mesenteroides SM isolated from carrot juice were dependent upon the sucrose concentration and beet extract content. The addition of beet extract increased the consistency index and bioconversion of sucrose in the carrot juice fortified with Phellinus linteus extract, showing the highest consistency value at 2% beet extract. The polyphenol content and antioxidant effect of fermented carrot beverage were increased as the content of beet extract increased. Particularly, the consistency of fermented carrot beverage was greatly increased by the cold storage for 120 hr. After the cold storage for 2 weeks, fermented carrot beverage fortified beet extract showed the red-purple color with higher color value (a) and the viable cell counts of $10^9$ CFU/mL.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.671-676
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• 2007

The effect of solid content on the physicochemical properties of rice porridge after reheating. The concentration of rice porridge was classified as solid content (12%, 10%, and 8%) by traditional Korean cooking methods. For reheating, packed rice porridge was boiled in water for 3 min and then cooled at room temperature ($25^{\circ}C$). The viscosity, soluble solid content and reducing sugar content of the rice porridge increased according to the solid content, while the blue value decreased. After reheating, the viscosities ($25^{\circ}C$) of all rice porridges decreased to 2.9-8.4%, compared to those of freshly made rice porridge, whereas the soluble solid content and reducing sugar content increased inversely according to the solid content of rice porridge. The SDI (starch digestion index) increased according to the solid content, whereas SDS (slowly digestible starch) the lowest in the solid content 12% porridge. Based on these results, it is favorable that the viscosity decrease after reheating was to be considered to ready-to eat rice porridges preparation.

• Food Science and Preservation
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• v.19 no.5
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• pp.652-658
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• 2012

This study, the changes in physicochemical properties and hesperidin content of Jeju-processed citrus fruits according to the harvest date were evaluate. The soluble-solid content, pH, and soluble solid-acid ratios gradually increased, but titratable acidity slightly decreased with a delay in the harvest date. The color index, lightness, yellowness, and turbidity slightly decreased whereas the redness slightly increased with a delay in the harvest date. The hesperidin content slightly decreased with a delay in the harvest date. Hesperidin, which is the major cause of juice cloudiness, decreased with a delay in the harvest date. These results suggest that later-harvested fruit juice is bound to be less cloudy.