• Korean journal of food and cookery science
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• v.12 no.1
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• pp.46-53
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• 1996

To investigate physicochemical and cooking properties of parboiled rice, choochung paddy processed to parboiled rice by three methods (PL, PT, PA) milled and examined hydration, cooking qualities and firming rate of cooked parboiled rice. The results were obtained as follows. The longer the steaming time during parboiling the larger EMC of soaked parboiled rice. Water uptake rate constants (k) of all the parboiled rice during soaking except for PT rice were generally increased than those of raw rice. The longer the steaming time during parboiling the greater volume increase rate constants ( $k_{v}$) of parboiled rice samples. The glelatinization temperature of parboiled rice flour by DSC was more increased than that of raw rice flour. Gelatinized entalpy was decreased and gelatinization content (%SG: degree of starch gelatinization) was increased by parboiling process. In cooking tests, parboiled rices were harder than raw rice and softness (reciprocal of hardness) was greater PT30, PA, PL30 in turns the cooking time of the parboiled rice took longer 3-10 min than that of raw rice, PL30 took longer time than anyother rices. Cooking water of parboiled rices could be observed lighter turbidities than that of raw rice. Firming rate constants of cooked rice during storage 24 hours were generally decreased by parboiling-processing. The time constants, reciprocal of firming constants of cooked PL30 rice were 2 times slower than those of cooked raw rice.e.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.5
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• pp.753-758
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• 2016

Moisture content influences physiological characteristics of microbes and physical structure of solid matrices during composting of animal manure. If moisture content is maintained at a proper level, aerobic microorganisms show more active oxygen consumption during composting due to increased microbial activity. In this study, optimum moisture levels for composting of two bedding materials (sawdust, rice hull) and two different mixtures of bedding and beef manure (BS, Beef cattle manure+sawdust; BR, Beef cattle manure+rice hull) were determined based on oxygen uptake rate measured by a pressure sensor method. A broad range of oxygen uptake rates (0.3 to 33.3 mg $O_2/g$ VS d) were monitored as a function of moisture level and composting feedstock type. The maximum oxygen consumption of each material was observed near the saturated condition, which ranged from 75% to 98% of water holding capacity. The optimum moisture content of BS and BR were 70% and 57% on a wet basis, respectively. Although BS's optimum moisture content was near saturated state, its free air space kept a favorable level (above 30%) for aerobic composting due to the sawdust's coarse particle size and bulking effect.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.900-904
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• 2004

Effects of gamma irradiation on brown rice quality were evaluated. Brown rice was irradiated at absorbed dose of 1, 3 or 5 kGy, and ground. Water uptake, pasting properties, and physicochemical characteristics of flour samples were tested. Water uptake rates of irradiated samples were higher than that of control, and were dose-dependent. Hydration capacity decreased in sample irradiated at 5 kGy due to leaching out of soluble compounds, whereas no differences were observed among other irradiated samples and control. Irradiation significantly decreased pasting properties as determined by amylograph. Gamma irradiation accelerated water evaporation at high temperatures (over $300^{\circ}C$) in test of weight-loss profile with thermogravimetric analyzer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.286-292
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• 1995

Proximate composition, dimension, water uptake and volume increase rates of three cultivars of Korean kidney beans, Pink(PKB), Red(RKB) and White(WKB) were compared. Significant differences in the proximate composition and calorie were not observed among samples. Hull removed samples showed the lowest ash content and the highest calorie. The rates of water uptake increased as the soaking temperature increased from 10~4$0^{\circ}C$. The moisture gain of the kidney beans during soaking showed a similar pattern to volume increase. Water uptake and volume increase rates were in the decreasing order of PKB, RKB and WKB. Moisture and volume gains held a linear relation with the square root of soaking time regardless soaking temperatures. The activation energies of water uptake and volume increase were 3033~3087 and 3077~ 3161 kcal/mole, respectively. The log time to reach a fixed moisture content showed a linear relation with soaking temperature regardless soaking temperatures. The z-values calculated from weight and volume changes decreased in proportions to the increase of hydration. The z-values of weight and volume to reach 50% hydration were 50.5~56.6$^{\circ}C$ and 48.4~61.2$^{\circ}C$, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.9
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• pp.630-635
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• 2011

As this study was estimation of factors of rapid OUR (Oxygen Uptake Rate) monitoring method. Experiment for estimating factors of optimal microorganism activity was carried out in this study. In addition to comparison and estimation of SCOD variation by OUR variation using real wastewaters. In consequence OUR value was highest when F/M ratio, pH and temperature were 0.03~0.05, 6.0~8.5 and $20{\sim}30^{\circ}C$ respectively. Oxygen consumption by nitrification was incomplete. OUR variation of SCOD was recognizable difference of degradable rate at before and after of inflection point OUR. This study used an experimental method for real time prediction of the influent of the sewage treatment plant for optimal operation is expected to be able to do.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.24-33
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• 1990

The changes in water uptake rate, cooking properties, color of rice grains and gelatinization properties of brown and milled rices during storage were studied. The brown and milled rices were stored at $4^{\circ}$ and $25^{\circ}C$ for 5 and 3 months, respectively. The water uptake rate constants of rices during hydration at $30^{\circ}$ were linearly decreased during storage. The volume increase rate also showed similar trend to the water uptake rate. The terminal point of cooking of milled rice at $100^{\circ}$ in a sealed brass vessel was about a half of that of brown rice. The cooking rate of milled rice was 1.8 times faster than that of brown rice. The cooking rate constant of both brown and milled rices linearly decreased with the increase of storage time. The L(lightness) value increased for brown rice grain and remained unchanged for milled rice grain during storage. The peak viscosity of rice flours by amylograph increased during storage, but enthalpy for gelatinization decreased, as measured by differential scanning calorimetry.

• Korean Journal of Microbiology
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• v.29 no.2
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• pp.117-122
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• 1991

In order to improve the removal ability of phosphate, Spheroplast fusions were performed among auxotrophic mutants of Aeromonas hydrophila isolated from waste water, named A13 and A14, Aci37 auxotrophic mutant of Acinetobactercalcoaceticus, and auxotrophic E. coli HR262/pCE27 carring pit gene. Eight fusants obtained from this experiment showed different biochemical characteristics. When the rate of phosphate uptake among fusants (F1-F8) was investigated in Phosphate Uptake Medium (PUM), F8 strain showed the highest rate for phosphate removal, 7 times as much as control after two hours incubation. The role of cations ($Mg^{++}$ ,$Ca^{++}$ , $K^{+}$ in phosphate uptade by F8 was also investigated in PUM without each salt. $K^{+}$ seemed to be crucial. Being compared with phosphate untake rate in PUM, that in PUM without $K^{+}$ was reduced 1.5 times. Therefore, by applying F8 strain and $K^{+}$ in practical environmental system, the increased efficiency in phosphate removal can be derived.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.571-576
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• 2004

Since anaerobic/anoxic/oxic process, which is a typical mainstream biological nitrogen and phosphorus removal process, utilizes influent organic matter as an external carbon source for phosphorus release in anaerobic or anoxic stage, influent COD/T-P ratio gives a strong influence on performance of phosphorus removal process. In this study, a bench scale experiment was carried out for SBR process to investigate nitrogen and phosphorus removal at various influent COD/T-P ratio and nitrate loadings of 23~73 and 1.6~14.3g $NO_3{^-}-N/kg$ MLSS, respectively. The phosphorus release and excess uptake in anoxic condition were very active at influent COD/T-P ratios of 44 and 73. However, its release and uptake was not obviously observed at COD/T-P ratio of 23. Consequently, phosphorus removal efficiency was decreased. In addition, the phosphorus release and uptake rate in anoxic condition increased as the nitrate loading decreased. Specific denitrification rate had significantly high correlation with organic materials and nitrate loadings of the anoxic phase too. The rate of phosphorus release and uptake in the anoxic condition were $0.08{\sim}0.94kg\;S-P/kg\;MLSS{\cdot}d$ and $0.012{\sim}0.1kg\;S-P/kg\;MLSS{\cdot}d$, respectively.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.6
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• pp.437-443
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• 2020

Biological phosphorus removal is accomplished by exposing PAO(phosphorus accumulating organisms) to anaerobic-aerobic conversion conditions. In the anaerobic condition, PAO synthesize PHB(polyhydroxybutyrate) and simultaneously hydrolysis of poly-p resulting phosphorus(Pi) release. In aerobic condition, PAO uptake phosphorus(Pi) more than they have released. In this study, cyanobacteria Synechococcus sp., which is known to be able to synthesize PHB like PAO, was exposed to anaerobic-aerobic conversion. If Synechococcus sp. can remove excess phosphorus by the same mechanism as PAO, synergistic effects can occur through photosynthesis. Moreover, Synechococcus sp. is known to be capable of synthesizing PHB using inorganic carbon as well as organic carbon, so even if the available capacity of organic carbon decreases, it was expected to show stable phosphorus removal efficiency. In 6 hours of anaerobic condition, phosphorus release occurred in both inorganic and organic carbon conditions but SPRR(specific phosphorus release rate) of both conditions was 10 mg-P/g-MLSS/day, which was significantly lower than that of PAO. When converting to aerobic conditions, SPUR(specific phosphorus uptake rate) was about 9 mg-P/g-MLSS/day in both conditions, showing a higher uptake rate than the control condition showing SPUR of 6.4 mg-P/g-MLSS/day. But there was no difference in terms of the total amount of removal. According to this study, at least, it seems to be inappropriate to apply Synechococcus sp. to luxury uptake process for phosphorus removal.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.679-686
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• 2010

To investigate the contribution of macroalgae to biogeochemical nutrients and carbon cycles, we measured the uptake rates of nutrients and $CO_2$ by Undaria pinnatifida using an incubation method in an acrylic chamber. From January to March 2010, U. pinnatifida was sampled at Ilkwang, a well-known area of macroalgae culture in Korea. The initial and final concentrations of nutrients, dissolved oxygen, total alkalinity, and pH of the chamber water were measured, and production/uptake rates were calculated using concentration changes, chamber volume, and incubation time. The production rate of dissolved oxygen by U. pinnatifida (n = 32) was about $5.4{\pm}4.0\;{\mu}mol\;g_{fw}^{-1\;}h^{-1}$. The uptake rate of total dissolved inorganic carbon (TDIC), calculated by total alkalinity and pH, was $7.9{\pm}6.5\;{\mu}mol\;g_{fw}^{-1}\;h^{-1}$. Nutrients uptake averaged $141.7{\pm}119.2$ nmol N $g_{fw}^{-1}\;h^{-1}$ and $15.0{\pm}9.1$ nmol P $g_{fw}^{-1}\;h^{-1}$. A positive linear correlation ($r^2$ = 9.6) existed between the production rate of dissolved oxygen and the uptake rate of total dissolved inorganic carbon, suggesting that these two factors serve as good indicators of U. pinnatifida photosynthesis. The relationships between fresh weight and uptake rates of nutrients and $CO_2$ suggested that younger specimens (<~50 g fresh weight) are much more efficient at nutrients and $CO_2$ uptake than are specimens >50 g. The amount of carbon uptake by the total biomass of U. pinnatifida in Korea during the year of 2008 was about 0.001-0.002% of global ocean carbon uptake. Thus, more research should be focused on macroalgae-based biogeochemical cycles to evaluate the roles and contributions of macroalgae to the global carbon cycle.