• Food Science of Animal Resources
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• v.24 no.3
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• pp.253-259
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• 2004

The effect of dietary clay mineral on meat quality in M. longissimus of Hanwoo (Korean cattle) bull beef during refrigerated storage (4$^{\circ}C$) was investigated. Experimental groups were divided into control (basal diet) and CT-1.25% (basal diet + 1.25% clay mineral) groups. There was no significant differences in proximate and fatty acid compositions between control and CT-1.25% groups. The pH of control group was significantly (p<0.05) changed during storage, but CT-1.25% group was little affected by storage time. CIE a＊ (redness), chroma (C＊) values and R630-R580 were significantly (p<0.05) decreased during storage for both groups. In particular, those values decreased more rapidly in the control group. The rate of metmyoglobin accumulation during storage increased more rapidly in the control group. Therefore, discoloration in the control group was more accelerated compared to the CT-1.25% group. TBARS (thiobarbituric acid reactive substances) which represents lipid rancidity were significantly (p<0.05) lower in CT-l.25% group than in the control. Water-holding capacity (WHC) was significantly (p<0.05) increased during storage for both groups, and CT-1.25% group had significantly (p<0.05) higher WHC than control group. Consequently, feeding of clay mineral (1.25%) was effective in increasing meat color stability and WHC, and retarding lipid oxidation than did control group.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.342-347
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• 1995

Experiments were conducted to investigate the effects of storage temperature and blanching treatment on the storage stability in order to extend the shelf life of Citrus junos. Chilling injury of Citrus junos was not observed at the temperature range of $0^{\circ}C{\sim}5^{\circ}C$. Respiration rate of Citrus junos classified into climacteric characteristics as storage time goes by increase of respiration rate. The $Q_{10}$ value of Citrus junos during storage appeared to have a narrow range of $2.3{\sim}2.4$ The decaying rate increased drastically at $20^{\circ}C$ ranging from 71.4% to 86.5%. It was not much influenced by the pretreatments but by the storage temperature. There was no difference in weight loss between the control and blanching treatment. The weight loss of Citrus junos at $20^{\circ}C$ appeared to be high during the 12 weeks period, and consequently the overall quality of Citrus junos was rapidly decreased. The ratio of brix to acid showed a slow increase for Citrus junos stored at $3^{\circ}C.\;At\;20^{\circ}C$, however, it increased rapidly and then decreased. This phenomenon was mainly due to the relatively high increase of brix, compared to the increase in acid content. Development of browning color in Citrus junos was mainly associated with Citrus junos peel, rather than with Citrus junos pulp.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.521-527
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• 1996

Some structural characteristics of kidney bean starches (3 varieties : Pink kidney bean, Red kidney bean and White kidney bean) were investigated. The amylose content and the ${\beta}$-amylolysis limit of kidney bean starches were $32.6{\sim}34.5%$ and $69.9{\sim}71.0%$, respectively. The kidney bean amylopectin was composed of super long chain of ${\overline{DP}}$ above 60 ($5.28{\sim}12.62%$), B chain of ${\overline{DP}}$ $45{\sim}60\;(29.85{\sim}33.65%)$ and A chain of ${\overline{DP}}\;10{\sim}20(22.94{\sim}29.85%).$ The chain distribution of kidney bean starches were different from variety to variety. The acid (2.2 NHCI) hydrolysis of kidney bean starches showed, as hydrolysis time increased, the patterns of three stages. The acid hydrolysis rate and iodine reaction of acid treated starches were different from variety to variety As acid hydrolysis time increased, the amylose and the ${\alpha}$-1.6-glucosidic linkage of amylopectin of amorphous state were gradually hydrolyzed. Finally, the chain of ${\overline{DP}}$ 20 of crystalline state was left in the acid treated starches.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.247-251
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• 1993

Physico-chemical characteristics of glutinuous rice during soaking treatment at different temperature for Yu-Kwa (Korean traditional glutinous rice cake) processing were determined. Crude fat and protein contents of soaked glutinous rice decreased up to 30% to 50%, respectively, compared to raw rice, but there was a little difference in soaking periods. As the soaking period increased pH of soaking solution was decreased from 6.4 to 3.3, while Brix was increased from 0.5 to 13.6. Titration acidity of soaking solution and soaked rice were increased to 22.9 and 3.4, respectively, as the soaking period increased to 9 days at $20^{\circ}C$ soaking, but it was increased rapidly to 29.8 and 4.0, respectively, at $30^{\circ}C$. The three kinds of free sugar such as glucose, sucrose and maltose were detected. Glucose was the major produced free sugar during soaking, sucrose was not detected after 1 day soaking period. Characteristics of amylographic viscosity on soaked rice showed that there are no difference in pasting temperature by the soaking time and temperature, but the maximum viscosity was drastically increased on $1{\sim}2\;day$ soaking period and decreased rapidly after $2{\sim}3\;day$.

• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.183-194
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• 2005

The mineralogical, physicochemical and thermal properties of the Myogi bentonite occurring in Japan were measured. A adsorption properties of U, Th, Ce and Eu ions on the Myogi bentonite were also investigated in different solution concentrations and pH conditions. The Myogi bentonite showed a strong alkaline character (pH 10.4), very high swelling, viscosity property and CEC, and a slow flocculation behavior due to the strong hydrophilic property. By the thermal analysis, the dehydroxylation of crystal water in bulk and clay fractions of the Myogi bentonite occur at $591^{\circ}C$ and $658^{\circ}C$, respectively, The adsorption experiments of ions such as U, Th, Ce and Eu were conducted for 0.2 g bentonites with 20mL solutions of various concentrations and different pH conditions with pH 3, 5, 7, 9, and 11. As a result, the Myogi bentonite showed excellent adsorption capacities for Ce, Th and Eu ions, whereas U ion showed very low adsorption capacity. Generally, Ce, Th and Eu ions showed the similar adsorption properties for the different concentrated solutions and pH conditions. These adsorption properties seem to be affected by the formation of various forms of chemical species and precipitation as well as ionic exchange reaction and surface adsorptions on smectite. Some associated zeolite minerals perhaps have some effects on the adsorption of U, Th, Ce and Eu on Myogi bentonite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.677-680
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• 1992

For quality evaluation of Korean cabbage kimchi during fermentation at $4^{\circ}C$ for 45 days, color change of kimchi juice was measured instrumentally. Chemical analyses of the kimchi juice showed that the kimchi has reached pH 4.2 and titratable acidity of 0.63% together with the highest vitamin C content, those values being obtained under the optimum ripening period, after 30 days of fermentation. The volume of kimchi juice increased until day 30 and was constant thereafter. The CIE-1976 $L^*$$a^*$$b^*$ color values increased until day 30 and then decreased. The ratio of color value $a^*$ to $b^*$ was 0.82 in the beginning, 0.98 at the optimum ripening period, and 0.94 under the over-ripening periods. The quality of kimchi could be estimated by using the $L^*$, $a^*$, $b^*$ values or the ratio of $a^*$ to $b^*$, alone or in combination with the juice volume.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.117-124
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• 2002

This study was carried out to investigate variation of heavy metal contents for feed materials during composting and to evaluate the effect of pre-treatment methods on heavy metal analysis. Dry ashing, $HNO_3-HClO_4$, aqua-regia, HCl reflux, $HNO_3-HClO_4-HF$, autoclaving methods of $HNO_3$, HCl, and $HNO_3(2+1)$ were used as pre-treatment for heavy metal analysis. In analyzing standard material SRM 2781, recovery efficiencies of pre-treatment methods were 50-60% for Cr and Zn, >100% for Ni, and 80-90% for Cd and Cu. Recovery efficiency of dry ashing for SRM 2781 was the lowest. In composting raw material, Cd concentration by autoclaving methods was 3 to 4 times higher than the other methods and recovery efficiency of dry ashing was also the lowest. During composting, Cd content was the highest in autoclaving. Cr and Cu concentrations were the lowest in dry ashing and aqua-regia, respectively. Variation coefficients of Pb and Zn between pre-treatment methods were generally low.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.185-193
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• 1976

The sterol compositions of the Pelecypoda, M. sultataria, S. sachalinensis, and the Gastropoda, H. discus hannai Inc, T. cornutus were investigated. The results areas follows: 1. The contents of the unsaponifiables and sterols of the Pelecypoda, M. sulcataria, S. sathalinensis, and the Gastropoda, H. discus hannai Ino, T. cornutus, are $12.0\%,\;11.8\%,\;and\;16.2\%,\;15.3\%$, respectively. 2. The complex sterols from the Pelecypoda and Gastropoda are well separated on Silica Gel HF 254 TLC impregnated with $15\%$ silver nitrate. 3. The prominent sterols of the Pelecypoda, M. sulcateria and S. sachalinensis, are 22-trans-24-norcholesta-5, $22-dien-3\beta-ol$ $3.0\%\;3.9\%$ 22-dehydrocholesterol $6.7\%,\;10.2\%$, cholesterol $39.0\%,\;48.6\%$ brassicasterol $14.1\%,\;13.8\%$ 24-methylenecholesterol $19.4\%,\;11.5\%$, stigmasterol $2.4\%,\;0\%$ $\beta-sitosterol\;10.5\%,\;11.9\%$, and fucosterol $4.3\%,\;0\%$. 4. Abalone, H. discus hannai Ino, and T. cornutus contain cholesterol $98.0\%,=97.5\% as main component with small amounts of 22-dehydrocholesterol, brassicasterol and desmosterol. In H. discus hannai rno, 24-methylenecholesterot and fucosterol are also found.

• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.219-224
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• 1976

The appearance of organochlorine pesticide residues in shellfish, seaweed, mud and water samples collected from south coast of Korean peninsula in September 1974 was surveyed to obtain the following results. 1) The residues in shellfish samples were found to be in the orders of Choongmoo > Yeosoo > Busan > Mokpo area, top-shell >short-necked clam > mussel > hard clam > red-shell, aldrin > ${\alpha}-BHC$ > heptachlor> ${\gamma}-BHC$ > dieldrin > heptachlor epoxide > endrin and in the range of $0-49\;{\mu}g/kg$ edible fresh muscle. 2) The residues in seaweed samples from Wando area were found to be in the orders of tangle > green laver > laver, ${\alpha}-BHC$ > ${\gamma}-BHC$ > aldrin > dieldrin > heptachlor > heptachlor epoxide > endrin and in the range of $0-60\;{\mu}g/kg$ dry matter. 3) The residues in water samples were found to be in the orders of Yeongsan River > Nakdong River > Seomjin River > Choongmoo shellfish farm, ${\alpha}-BHC$ > ${\gamma}-BHC$ > aldrin > heptachlor > dieldrin > heptachlor epoxide > endrin and in the range of $0-180\;{\mu}g/kl$ while those in mud samples were in the order of ${\alpha}-BHC$ > ${\gamma}-BHC$> aldrin > dieldrin > heptachlor > heptachlor epoxide > endrin and in the range of $0.7-18\;{\mu}g/kg$ dry matter. It should be noted that BHC contents of water samples from Yeongsan and Nakdong rivers were far above the recommended environmental levels in USA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1124-1129
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• 2005

Functional activities of low molecular weight substances purified from pepsin hydrolysates of four different seaweeds; Costaria costata, Enteromorpha prolifera, Grateloupia filicina and Porphyra tenera, were inves-tigated. Each pepsin hydrolysate of Costaria costata, Enteromorpha prolifera, and Grateloupia filicina resulted in three peptide peaks on Bio-Rad P2 gel chromatography pattern, while that of Porphyra tenera showed 2 peaks. Peak 1 of Porphyra tenera showed the highest antioxidative activity followed by peak 2 of Porphyra tenera and peak 2 of Costaria costata in order Peak 1 of Porphyra tenera showed the highest ACE inhibitory activity followed by peak 3 and peak 2 of Enteromorpha prolifera in order. Peak 1 and peak 2 of Porphyra tenera, and peak 2 of Enteromorpha prolifera showed the highest antityrosinase activity followed by peak 3 of Enteromorpha prolifera. Peak 1 of Enteromorpha prolifera showed the highest antitumor activity followed by peak 2 of Costaria costata, peak 3 of Enteromorpha prolifera, and peak 3 of Grateloupia filicina in order. Porphyra tenera showed the highest functional activities, which is thought to be due to its high protein content. Structure and amino acid sequence of low molecular weight peptide of Porphyra tenera should be analyzed in the further study.