• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.637-645
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• 1991

Physicochemical factors affecting cooking and eating quality of rice and their mechanisms were investigated. The stickiness of cooked rice was negatively correlated with amylose content(r=0.58, p<0.05) and protein content(r=-0.72, p<0.01), but not affected by crude fat content of rice. The ultrastructure of cooked rice grain showed the progressive gelatinization of starch from the periphery toward the center of the endosperm as water and heat energy diffused into. The rate of water diffusion appears to be dependent on the cell arrangement in the endosperm and the protein content of milled rice. Once water and heat reach the starch granules, the rate of in situ gelatinization of starches appears to be dependent on their own gelatinization temperature range and amylose content. Protein acts as a barrier for the swelling of starch and water diffusion in two ways : 1) by encasing starch granules in the starchy endosperm, and 2) by forming a barrier between the subaleurone layer and the starchy endosperm. Therefore, the separation and fragmentation of the outermost layers of the endosperm occurred more easily in the low-protein content rices, and was associated with increases of solids lost in cooking-water at 95$^{\circ}C$ and stickiness of cooked rice.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.2
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• pp.27-31
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• 2002

This study was measured weight loss, total ascorbic acid, titratable acidity, soluble solids content and overall appearances to investigate the effect of corrugated fiberboard box coated with functional materials ; R, G, X box, R, G and X box and Con(double wall corrugated fiberboard) box during storage at $25^{\circ}C$. Weight loss of mandarin of control, corrugated paperboard box coated with functional materials(Y-, R-, G-box) after 8 days were 2.56% to 3.67%. There was not different to weight loss among the four kind of packages. Titratable acidity and soluble solids content of packages was not significant. Total ascorbic acid content(TAA) of mandarin packed with R-box and Y-box was 10% higher than that of control after 8 days. Decay ratio of R-box, Y-box, G-box and control was 4%, 10%, 10% and 8%, respectively. Overall appearance of R-box was the best.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.124-130
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• 2005

Landfilling is most widely used as the final disposal tool of solid wastes. Solid wastes landfilled are stabilized by microbial degradation which is affected by several factors such as moisture, oxygen, pH, alkalinity, sulphate, nutrient, inhibitor, hydrogen, and temperature. Especially moisture plays a major role in microbial degradation. In this study, the effects of moisture on the degradation of municipal solids waste (MSW) were investigated. Four lysimeters with four different levels of moisture content i.e., 20, 30, 40, and 50% were operated; lysimeters were packed with MSW, and anaerobically operated. Anaerobic lysimeters with higher moisture content produced more $CO_2$ and landfill gases (LFG). It means that the moisture has a positive effect on the microbial degradation.

• Food Science and Preservation
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• v.3 no.2
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• pp.155-170
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• 1996

In order to determine the physiolosical characteristics of plum fruits(Oishi wase) during maturation and guilty according to temperature after harvest, (2-chloroethyl) phosphonic acid(ethphon) 390ppm was sprayed on plum tree 11days before commercial matuarity in Suwon area. And also this study was acted to investigate fruits quility(Formosa) influenced by temperature(room, low) and polyethylene films(0.03, 0.06, 0.1mm), 1. Effect of ethphon on the fruits maturation and fruits(Oishi wase) quility according to temperature ofter harvest. Ethephon stimulated fruits ripening but the firmness was reduced rapidly. Soluble solids and titratable acidity was not very different than each treatment. Carbon dioxide and ethylene production were advanced and the production peak were shown earlier by ethephon treatment as compared with control fruit. Anthocyanin development was enhansed rapidly by ethephon treatment but it exerted a bad influence on fruits color after harvest, The soluble sugars in fluits were mainly glucose, sucrose, and fructose. Those content were higher in treated fruit than control. The organic acid was mainly malic acid. The shelf life was less than about 5days at room temperature and about 10 days at low temperature. 2. Fruits(Formosa) quility as affected by polyethylene film bagging. The polyethylene films well maintained the firmness both room and low temperature. Low temperature was more effective in maintaining titratable acidity than room temperature, especially polyethylene films. On the Other hand, soluble solids content was not shown wide differance between room and low temperature. Polyethylene film showed a high resperation rate, the rate was higher at room temperature than low temperature and thicker films revealed higher rate. Otherwise, ethylene production was low in all treatment Polyethylene film inhibited the coloration of fruits, decreased anthocyanin content. Fruits coloration delayed by low temperature in control. The shelf life of plum fruits was about 6 days at room temperature and 13 days at low temperature in control Polyethylene film had no advantage on shelf life both at room and low temperature.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.706-712
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• 2013

This is the basic study on the extraction characteristics of Omija (Schizandra chinensis) for juices of Korean traditional foods. Extraction is being performed as 25 times of the solvent ratio at room temperature and at $65^{\circ}C$ with deionized water, tap water and Cheong-song mineral water which have high contents of Ca and Mg. The overall good results of the extraction conditions are calculated from the values of L (Lightness), redness (a), yellowness (b), soluble solids content, acidity, pH levels and the DPPH radical scavenging activity by using the electron donating ability (EDA). The results are as follows: 12 hours of room temperature and 6 hours at $65^{\circ}C$ were good extraction times. The Cheong-song mineral water at $65^{\circ}C$ is available for rapid extractions when compared to deionized water and tap water. A longer extraction time shows lower values of acidity but increasing values of soluble solids content and DPPH radical scavenging activity when using the electron donating ability. The best sequences for the extractions are Cheong-song mineral water followed by tap water and distilled water after overall consideration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.80-84
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• 2000

To investigate the effect of packaging condition on functional MA films laminated (30CE, 50CE), corrugated paperboard box (control), 30LDPE, and 50LDPE pouches on the freshness extension of Fuji apples, the weight loss, firmness, total ascorbic acid, titratable acidity, soluble solids content and appearence were evaluated at 5$^{\circ}C$ after 75 days. Weight loss of 30CE and 50CE, and 30LD and 50LD was 0.4 to 0.5%, and 0.2%, but control was 2.7%. Firmness in film packages was higher than that of control, and CE packagings were higher than LD. Total ascorbic acid content of Fuji apple in control after 75 days was 2.12 mg%, that of control was decreased by 42%, those of LD packagings were 31% and 29%, and those of CE were 24% and 22%. Titratable acidity and soluble solids content in control changed more than that of MA film packagings. Overall appearence of 'Fuji' apples in CE packagings was better than that of control.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.526-534
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• 2023

To improve usability of super sweet corn, extracts were prepared with hydrolytic enzyme and changes in physicochemical and antioxidant properties were analyzed. Soluble solids and reducing sugars contents were higher in all enzyme treatment groups than in the control. When enzyme treatment time increased, contents of soluble solids and reducing sugars were also increased. There was no significant difference in lightness between treatment groups, with redness showing the highest value in the control and yellowness showing the highest value in the invertase treatment group. Free sugar content in the control was the lowest. However free sugar content in the enzyme combination treatment group was increased by more than four times compared to that in the control. Contents of ascorbic acid, flavonoids and polyphenols were higher in the enzyme treatment group than in the control. In particular, the enzyme combination treatment group showed the highest content. DPPH and ABTS radical scavenging abilities were significantly higher in all enzyme treatment groups than in the control. Radical scavenging abilities of cellulase treatment group and enzyme combination treatment group showed high activity. The activity increased when enzyme treatment time increased. The combined enzyme treatment method for super sweet corn was suitable for food processing.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.314-322
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• 2017

The aim of this study was to determine suitable oxygen transmission rate (OTR) films for modified atmosphere (MA) storage of asparagus spears (Asparagus officinalis L.), and to examine the related changes in asparagus spear quality. Asparagus spears were packed with 10,000, 20,000, 40,000, 70,000, and $100,000cc/m^2{\cdot}day{\cdot}atm$ OTR film treatments for MA storage, and perforated film (conventional storage) was used as the control. The fresh weight loss rate was less than 1% in all OTR film treatments but not in the control. In all OTR film treatments, ethylene content rapidly increased on the first day of storage, and gradually decreased thereafter to $2.0{\mu}L{\cdot}L^{-1}$ by the final storage day. In the 10,000 cc and 20,000 cc OTR film treatments, carbon dioxide content was maintained within the permissible range for asparagus spears under recommended controlled atmosphere (CA) and MA conditions (5-12%). The oxygen content was maintained between 12% and 20% in all OTR film treatments. Hue angles and total chlorophyll content were highest in the 10,000 cc OTR film treatment in both tips and stems. Visual quality was maintained at a saleable level only in the 10,000 cc OTR film treatment until the final storage day (25 days). Based on sensory evaluation, the least off-odor was detected in the 10,000 cc OTR film treatment, and the most in the control treatment. While the soluble solids content decreased with all film treatments, it was maintained at the highest level in the 10,000 cc OTR film treatment. Vitamin C content decreased with all film treatments during storage, but was maintained at higher levels in the 10,000, 20,000, and 40,000 cc OTR film treatments. The firmness of tips and stems increased with storage duration in all film treatments, stems were firmer under the perforated film, 10,000, and 20,000 cc OTR film treatments. Given these results, the 10,000 cc OTR film treatment is considered the most appropriate for MA asparagus spear storage since visual quality and soluble solids content were maintained, and fresh weight loss, vitamin C content, off-odor, and yellowing were suppressed during storage.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.304-311
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• 1999

This experiment was conducted to find out the optimum condition of aeration rates for removal of malodor and to improve the compost quality. The aspect of ammonia emission and amounts of volatilization were investigated in the enclosed composting reactor of 242 liters piled with mixed materials of dairy manure and rice straw, which adjusted to 65% of initial moisture content and controlled by four different aeration rates. Mature temperature increased suddenly in initial composting time and decreased with Increasing aeration rates. The treatment of $1.79l\;min^{-1}kg\;dry-solids^{-1}$ results in overcooling and rapid drying of composting materials because of too much aeration. The average concentration of ammonia emitted from composting for 24 days was the range of 25.3 to $239.8mg\;l^{-1}$ and was highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.90. 0.18 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. The range of maximum concentration by different aeration rates was $335{\sim}2279mg\;l^{-1}$ and it wan highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.18, 0.09 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. Relationship between the ammonia concentration emitted and temperature matured under different aeration rates showed an exponential positive correlation with 1% significance and had a trend of clear increase in ammonia concentration with increasing temperature over $50^{\circ}C$. Most of ammonia volatilized within plays after composting. The volatilization rate of ammonia ranged from 0.056 to 0.453 per dry solids of materials and it was highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.18, 0.09 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. Amounts of ammonia volatilized under composting condition of this experiment was estimated to be highest in the aeration range of 0.9 to $1.0l\;min^{-1}kg\;dry-solids^{-1}$.

• Food Science and Preservation
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• v.8 no.2
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• pp.169-174
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• 2001

Chemical analysis and optimum preparation conditions for fig jam were investigated. Soluble solids, acid content and vitamin C of fig was 12.20。Brix, 0.14% and 2.27 mg/100g, respectively. Carbohydrate in fig juice was consisted of 54.43% glucose and 44.53% fructose. Potassium content of fig was 178.0 mg/100g. Moisture content and total sugar of fig fruit was 88.35% and 9.47%. In preparation of fig jam, the addition of 0.2% Citrus natsudaidai juice and 0.5% C. lemon juice as acid source was the best in regard with color and flavor determined by sensory evaluation. The ratio of sucrose : honey : oligo sugar(70:20:10) was also the best in addition of sugar source 60%(w/w) in total. Fig jam prepared in this experiment was better than that of commercial products in sensory evaluation, and microbial growth of this product was not recognized for one month at 30$\^{C}$.