• Food Science and Preservation
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• v.13 no.1
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• pp.30-36
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• 2006

Milk protein-gum conjugates were prepared by Maillard reaction and added to dough to investigate the possibile use of them as anti-staling agents in bread Four different types of conjugates were added to dough, i.e., $casein-\kappa-carrageenan$ (CK), casein-sodium alginate (CA), $whey-\kappa-carrgeenan$(WK) and whey-sodium alginate (WA). Their addition to flour increased the gelatinization temperature, water absorption and development time of the dough. Extensogram showed the increased resistance to extension of the doughs resulting from the addition of the conjugates. Moisture content of the breads decreased during storage at $5^{\circ}C$ for 4 days. The breads added with conjugates had lower extents of the decreases than non-treated degrees and maintained higher moisture content than non-treated bread after 3 freeze-thaw cycles. The storage degrees at $5^{\circ}C$ for 4 days affected the increased bread hardness, but, addition of WA conjugate decreased extents of the increases. Therefore, milk protein-gum conjugates, especially WA conjugate, contributed to retarding staling of breads

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.722-727
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• 2012

In order to improve the physical properties of brown rice by hydration and cooking, the amount of water absorption, hardness, reducing sugar, and minerals were measured for rice (NR), brown rice (NBR), and scratched brown rice (SBR). The amounts of water absorption were present in the order of NBR<0.07 SBR<0.20 SBR=NR after 210 min. The moisture contents of gelatinization rice were significantly different by degree of milling and scratch. The hardness of gelatinization rice were present in the order of NR<0.20 SBR<0.07 SBR

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.93-98
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• 2005

The effects of the presence of a submerged plant, Zizania latifolia, on physico-chemical characteristics, including Eh, pH, and concentrations of nitrogen and phosphorus in the sediments were studied under pot culture condition. It was shown that Eh value at reduced layer of the sediments was higher in the planted pots than in the non-planted. It was also revealed that $NH_4^+-N$ concentration of the sediments in the planted pots was lower than that of the non-planted, which might be due to the uptake by the plants. In contrast, $NO_3^--N$ concentration in the sediment increased in the presence of the plants compared to the non-planted, which might be attributed to oxygen released from the roots to the reduced layer. The concentration of organic phosphorus in the sediments was much higher than that of NAIP at the beginning of the planting experiment. However, at the end of the experiment, it was reversed; NAIP concentration was much higher than that of organic phosphorus, possibly indicating the transformation of organic phosphorus to NAIP during the experimental period. Both concentrations of $NH_4^+-N$ and $PO_4^{3-}-P$ in the overlying and percolated water were lower in the planted pots than in the non-planted. The concentration of $NO_3^--N$ in the percolated water, however, was higher in the planted pots than in the non-planted. The data was discussed with regard to the potential effects of a submerged plant on dynamics of phosphorus and nitrogen in the rhizosphere of the sediment.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.249-255
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• 1995

This study was conducted to investigate the effects of some soil conditioners, such as polyacrylamide(PAM), polyvinylalcohol(PVA) and Bitumen emulsion, on aggregate formation and stability, wetting angle, sorptivity and penetrability of the soil with different textures : sand, sandy loam, loam and clay loam. A pot experiment was carried out to find out the effect of treatment on the germination and growth of lettuce with three textures : sand, sandy loam and silt loam. Soil aggregates larger than 2mm in untreated soils at dry condition were naught in sand, 45% in sandy loam, 80% in loam and 90% in clay loam. Treatments of soil conditioners tended to increase the occurrence of soil aggregate larger than 2mm, which were 20~25% in sand, 55~75% sandy loam, but not affected greatly aggragate occurence in loam and clay loam. The aggregate instability was decreased by the soil conditioner treatment. The wetting angles of the soils were greatly changed by hydrophobic of Bitumen, but those were changed slightly by PVA and PAM application. The sorptivity and penetrability data indicated that the effects of different materials on these parameters differed depending upon soil texture. Application of PVA and PAM were no effect exceptive in sand. Application of Bitumen revealed that water movement was not showed in all soils. The germination rate, root weight and top plant weight of lettuce were increased in all soils by PAM treatment as compared to untreated soils. Particularly the greater effect was occurred in sand soil than in sandy loam and silt loam. PAM increased greatly the moisture content and air phase of soils.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.20-26
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• 2016

This study invesigated the physicochemical properties of rice flours from conventional and high-yielding rice varieties in order to enhance usability processing of high-yielding rice varieties. Moisture content was not remarkably different among rice flours by cultivar. The highest content of total free sugars was detected in Hopum rice. Apparent amylose content of Anda was higher than that of other rice varieties. The total amount of amino acids was highest in Anda rice among the rice cultivars. Contents of vitamin $B_1$ in Hanarum were highest among the rice cultivars. Initial pasting temperature was lowest in Anda rice ($60.10^{\circ}C$). Hanarum rice showed the lowest setback values among the rice flours. Therefore, Anda and Hanarum rice cultivars were suggesting the possibility of a processed rice food source.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.347-351
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• 2014

We studied the green synthesis and antibacterial activity of chitosan-silver (Ag) nanocomposite films for application in food packaging. Green synthesis of Ag nanoparticles (AgNPs) was achieved by a chemical reaction involving a mixture of chitosan-silver nitrate ($AgNO_3$) in an autoclave at 0.1 MPa, $121^{\circ}C$, for 15-120 s. The formation of AgNPs in chitosan was confirmed by both UV-Visible spectrophotometry and transmission electron microscopy (TEM) and the effects of chitosan-$AgNO_3$ concentration and reaction time on the synthesis of AgNPs in chitosan were examined. The resulting chitosan-Ag composite films were characterized by various analytical techniques and their antibacterial activity was evaluated based on the formation of halo zones around films, indicating inhibition of the growth of Escherichia coli. A fourier-transform infrared (FTIR) spectroscopy analysis showed that free amino groups in chitosan acted as effective reductants and AgNP stabilizers. The composite films exhibited enhanced antibacterial activity with increasing Ag content on the surface of as-prepared composite films.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.261-266
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• 1984

Soymilk residue was washed separately with acetone, ethanol, isopropyl alcohol and n-hexane, and then dried at $45^{\circ}C$. The dried residues were evaluated for drying rate, color and chemical and functional properties. Washing with acetone resulted in the shortest drying time (1hr) and the highest in protein content (48.8%) and in Hunter 'L' value. The dried residues after treatment with acetone and alcohols showed relatively high values of 4.3-4.7g/g and 8.5-8.7g/g in oil and water absorption, respectively. Addition of the acetone treated residue to wheat flour at a level of 10% affected little in Amylograph viscosity while those treated with other solvents caused a significant decrease in the viscosity.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.61-75
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• 2020

In this study, the environmentally friendly material charcoal was added to ricehusk, an agricultural by-product, and sawdust, which emerges during the sawing process, to produce board by mixing ratio and concentration levels of ricehusk and charcoal; it then investigated its physical properties for development purposes and achieved the following results. The water absorption and thickness swelling of the compounded board produced per adding ratio of ricehusk and charcoal showed a gradually decreasing tendency along with the increase in adding ratio of the charcoal, and as the density of the compounded board increased, the water absorption decreased, while the thickness swelling increased. The internal bond strength of the compounded board had indicated its highest value of 0.49N/㎟ at the density of 0.7g/㎤. This satisfied the quality standard for KSF 3104 Particleboard. The internal bond strength of the compounded board manufactured per adding ratio of ricehusk and charcoal showed a steady decrease with the decrease in the adding ratio of ricehusk, and an increase in the addingratio of the charcoal. Also, in cases when the ratio of the ricehusk and charcoal by KSF 3104 quality standard were 35:5 and 30:10, it satisfied the quality standard of 15.0-type, whereas it satisfied the 13.0-type quality standard if the ratios were 25:15 and 20:20. It showed a tendency of increasing hardness of the compounded board with the increase in density, and decreasing hardness with the increase in the adding ratio of the charcoal.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.205-210
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• 2008

Sedum kamtschaticum has been used as one of the native valuable plants for ornamental purpose. This experiment was conducted to find out the optimum media for pot cultured Sedum kamtschaticum using peatmoss and coir-based mixtures. Four mixtures such as peatmoss:perlite(5:5, v/v), peatmoss:perlite(7:3, v/v), coir:perlite(5:5, v/v), and coir:perlite(7:3, v/v) were used. Plants were irrigated with a Sonneveld solution in an ebb & flow system. The content of T-N, K, and Ca in the peatmoss-based media was higher than those of the coir-based media. The concentration of T-N, K, and Ca in the shoots of Sedum kamtschaticum increased when plants were cultured with peatmoss-based media. In the peatmoss-based media, plant growth, such as number of branches, leaf length and shoot fresh and dry weights, were significantly increased than those of plant grown in the coir-based media. As the results, the optimum media for pot cultured Sedum kamtschaticum in an ebb & flow system was considered to be the peatmoss-based mixtures.

• Polymer(Korea)
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• v.33 no.2
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• pp.104-110
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• 2009

Demineralized boneparticle (DBP) has been widely used as and a powerful promoter of new bone growth. In this study, DBP sponges were chemically crosslinked and characterized for the potential application of tissue engineered scaffolds. The DBP sponges prepared by crosslinking with EDC. 0.1, 0.2 or 0.3% pepsin was applied to DBP dissolved in 3% (v/v) acetic acid aqueous solution for 48 hrs. The prepared sponges were crosslinked by 1, 5, 10, 50 or 100 mM of EDC solution concentration and then were lyophilized. The DBP sponges were characterized by SEM, FT-IR and DSC and analyzed in terms of their porosity and water absorption ability. The cellular viability and proliferation were assayed by MTT assay. Our investigation revealed that 0.2$\sim$0.3% of pepsin and 50$\sim$100 mM of EDC produced DBP sponges with good physical characteristics. In conclusion, DBP sponge prepared under these conditions is potentially useful for the applications of tissue construction.