• Food Science of Animal Resources
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• v.31 no.3
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• pp.469-476
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• 2011

This study was conducted to evaluate the functional effects of adding oyster shell powder on the quality properties and storage stability of emulsion-type pork sausages to substitute phosphates as a curing agent. Seven treatments were prepared: T1 (Control), T2 (0.3% STPP), T3 (1.5% NaCl), T4 (1.5% NaCl + 0.5% whey protein), T5 (1.5% NaCl + 0.5% whey protein + 0.15% oyster shell powder), T6 (1.5% NaCl + 0.5% whey protein + 0.3% oyster shell powder), and T7 (1.5% NaCl + 0.5% whey protein + 0.5% oyster shell powder). Significant differences were observed for ash in the proximal analysis. Adding 0.5% oyster shell powder significantly increased pH values when compared to the other treatments. Pork sausages with 0.3% oyster shell powder had significantly improved water holding capacity and cooking loss. Adding oyster shell powder (0.15, 0.3, and 0.5%) resulted in significantly higher hardness, cohesiveness, springiness, and chewiness values than those in the other treatments. No significant differences were observed among treatments during 14 d of cold storage at $4^{\circ}C$.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.8
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• pp.717-724
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• 2013

Urea-SCR technology is known as one of the powerful NOx reduction systems for vehicles as well as stationary applications. For its consistent and reliable operation in vehicle applications, however, the freezing and melting of the urea solution in cold environments have to be resolved. In this study, therefore, a numerical study of three-dimensional unsteady problems was analyzed to understand the urea freezing and heating phenomena and heat transfer characteristics in terms of urea liquid volume fraction, temperature profiles, and phase change behavior in urea solutions with time by using the commercial software Fluent 6.3. As a result, it was found that the freezing phenomenon proceeds with a phase change from the tank wall to the center, whereas the melting phenomenon occurs faster in the upper part of the storage tank by natural convection and in the adjacent part of the coolant pipe than in other parts. Furthermore, approximately 190 s were required to obtain 1L of urea solution using a 4-coiled coolant heater under conditions of $70^{\circ}C$ and 200 L/h.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.403-414
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• 2013

This study evaluated the physicochemical and microbiological characteristics and antioxidant properties of yogurt samples fermented with lactic acid bacteria (LAB) obtained from pickled cabbage. API 50 CHL systems and 16S rRNA nucleotide sequence analyses revealed that the isolates were Lactobacillus casei PC05 and L. acidophilus PC16. Cell counts, titratable acidity, and viscosity of the yogurt samples fermented with L. acidophilus PC16 were significantly higher than those of the samples fermented with L. casei PC05 (P<0.05). The detected cell counts and physicochemical properties were significantly lower in plain yogurt than in soy yogurt (P<0.05). Yogurt samples fermented with L. acidophilus PC16 exhibited higher antioxidant activity, measured as ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and chelate ferrous ions, than those fermented with L. casei PC05. However, the ability to scavenge superoxide anions and superoxide dismutase (SOD) activity were significantly (P<0.05) higher in yogurt samples fermented with L. casei PC05 compared to those in samples fermented with L. acidophilus PC16. The antioxidant activity of soy yogurt was significantly (P<0.05) higher than that of plain yogurt. The antioxidant activity of the tested strains resulted in lipid peroxidation inhibition (in vitro), which may be related to the elimination of free radicals, chelating ability, and reducing power. There were no significant differences in the physicochemical properties and antioxidant activities of the yogurt samples during cold storage.

• Fashion & Textile Research Journal
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• v.17 no.4
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• pp.657-665
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• 2015

This study evaluated the thermoregulatory properties of functional thermal underwear ('heating underwear') in markets using a thermal manikin and human wear trials. One ordinary thermal underwear (ORD) and two functional thermal underwear (HEAT1 and HEAT2; manufactured goods, HEAT1: moisture absorbing heat release mechanism, HEAT2: heat storage, release mechanism) were chosen. Thermo-physiological and subjective responses were evaluated at an air temperature of $5.0{\pm}0.5^{\circ}C$ and air humidity of $30{\pm}5%RH$ with five male subjects ($21.6{\pm}1.3yr$ in age, $178.0{\pm}5.9cm$ in height, $68.2{\pm}5.9kg$ in body mass). Experimental conditions consisted of four ensembles that included winter clothes (Control: no underwear, ORD, HEAT1, HEAT2). Water-vapor resistance was greater in fabric of HEAT1 than others. The results were: 1) Total thermal insulation (IT) using a thermal manikin were not greater for HEAT1 (0.860clo) and HEAT 2 (0.873clo) than for ORD (0.886clo). 2) There were no significant differences in rectal temperature, mean skin temperature, heart rate and total body mass loss between the four conditions. Microclimate clothing temperature on the back was greater for ORD than for HEAT1 and HEAT2. Subjects felt more comfortable with HEAT1 than for others at rest. HEAT2 was higher in microclimate humidity when compared to other conditions. The results suggest that thermoregulatory properties of 'heating underwear' in market did not differ from those of ordinary thermal underwear in terms of total thermal insulation and thermoregulatory responses in a cold environment.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.17-22
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• 2011

In this study, formaldehyde in various fisheries products was previously derivatized with acetylacetone and subsequently analyzed by using HPLC-PDA. The formaldehyde contents ranged from 0.07 to 73.74 mg/kg. The compound was significantly higher in both mollusks (0.34-12.38 mg/kg) and crustaceans (0.09-73.74 mg/kg) than in fish (0.07-3.35 mg/kg) and shellfish (0.50-3.90 mg/kg). This difference was due to storage time and temperature. In general, fish and shellfish are sold live or in refrigerated form with shorter a shelf-life, but mollusks and crustaceans are distributed in cold or frozen systems with a longer shelf-life. Using food intake data from a report of the National Health and Nutrition Survey, the daily human exposure level to formaldehyde was 0.58% of the ADI. The results from this study might provide fundamental information to confirm naturally-originating or fraudulent formaldehyde treatment in fisheries products.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.426-433
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• 1990

The conditions for immobilization of the partially purified ${\beta}-galactosidase$ form Bacillus subtilis HP4 and the properties of the immobilized enzyme have been investigated. The crude enzyme precipitated with cold acetone was purified about 68-fold through DEAE-cellulose and sephadex G-100 chromatography and its recovery was 19.9% The optimal conditions for Immobilization of enzyme were obtained in 2%(w/v) sodium alginate, 15%(v/v) enzyme solution and 2%(w/v) calcium chloride, and also the optimal stirring thme was 2 hours on the above conditions. The optimum temperature and pH values for immobilized enzyme were $55^{\circ}C$ and 6.5, respectively. Its residual activity was show 25% after heat treatment for an hour at $65^{\circ}C$, and found its high stability in pH 6.0 to 8.0. The enzyme activity was not affected b)· EDTA, 2-mercaptoethanol, KCN, protective agents, and other methal ions except Hg ion and Cu ion. The $K_m\;and\;V_{max}$ values of the immobilized enzyme on ONPG were $1.82{\times}10^{-2}M\;and\;3.57{\times}10^{-8}mole/min$, whereas those on lactose were $2.94{\times}10^{-2}M\;and\;1.68{\times}10^{-7} mole/min$, respectively. The remained enzyme activity for the immobilized enzyme was 95%t of original activity after storage of 40 days at $4^{\circ}C$, and when reused for 5 times was 81%. When skim milk(4.8% lactose) and 5% lactose solution were reacted with the immobilized enzyme(250 units/g) of lactose were 51% and 43%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.637-642
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• 1996

This study was carried out to investigate the change of palatability improvement of cooked meat by the physico-chemical properties and sensory characteristics as aging at $3^{\circ}C$ after thawing of frozen Holstein tenderloin. Shear force value(SFV), myofibrillar fragmentation ratio(MFR), appearance of 30ki1o dalton (30KD) component, raw meat aroma, tenderness, palatability of cooked meat, content of free amino acid and ATP related compound were measured. Raw meat aroma (p< 0.01), tenderness(p<0.05), SFV(p<0.05), MFR(p<0.01) and 30KD(p<0.001) of unfrozen beef tenderloin aged at $3^{\circ}C$ were superior than frozen beef tenderloin. As aging at $3^{\circ}C$ after thawing of frozen beef tenderloin SFV(p<0.05) decreased, MFR(P<0.001) and 30KD(p<0.001) increased, and raw meat aroma and tenderness improved(p<0.05). Also, cooked meat aroma, texture and palatability improved(p<0.05), without changing the taste. The content of aspartic acid and leucine of tenderloin aged thawing of frozen beef abounded were more than frozen beef(p<0.05), concentration of IMP(P<0.05) decreased, the hypoxanthine(p<0.05) and inosine increased.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.671-680
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• 2007

Objectives : The purpose of this study was to examine the effect of Haeyeol-tang on infectious disease of respiratory system. Methods : Haeyeol-tang was used by cold storage after dilution with 1, 10 and $100{\mu}g/ml$ of PBS, from dried material as extracted material with extraction with 50% ethanol. Statistical significance was examined through measuring TNF-$\alpha$, RT-PCR, DPPH, nitric oxide(NO), and MTT of Raw264.7 cells activated with LPS. Results : For the toxicity experiment of Haeyeol-tang, almost no toxicity was shown on cells in the concentration ranges of 1, 10 and $100{\mu}g/ml$. For the effect of NO production, Haeyeol-tang showed significant (p<0.001) decrease of NO production, according to its concentration. For the effect on the eliminating activity of DPPH radical, Haeyeol-tang showed increasing tendency of eliminating activity of DPPH radical, according to its concentration. For the effect on revelation of NOS2 enzyme, Haeyeol-tang showed inhibiting tendency against the revelation of NOS2, according to its concentration. For the effect on the TNF-$\alpha$ production, Haeyeol-tang showed significant (p<0.001) decrease of TNF-$\alpha$ production. Conclusions : This result means that Haeyeol-tang is effective for anti-inflammation, as well as excellent effect for anti-oxidation and anti-aging.

• Microbiology and Biotechnology Letters
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• v.33 no.4
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• pp.248-254
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• 2005

One hundred thirty nine bacteria were isolated from rotten onions collected from main producing districts, Chang-Nyung, Eui-Ryung, and Ham-Yang in Korea. The $18\%$ (25 strains) of bacterial isolates have carboxymethylcellulase (CMCase) activity and the $53\%$ (74 strains) have polygalacturonase (PGase) activity. Thirty one among randomly selected 45 strains of PGase producing bacteria have pathogenicity to onions. The isolates were classified into Pseudomonas sp. (18 strains), Bacillus sp. (11 strains), Yers-inia sp. (7 strains), and others (9 strains) on the basis of FAMEs patterns. Eighteen strains of Pseudomonas sp. were mainly divided into three cluster in the dendrogram and only the two clusters of them showed pathogenicity to onions. CMCase and PGase activities of Pseudomonas sp. weaker than those of Bacillus sp.. However, the pathogenicity of pseudomonas sp. to soften onions was stronger than that of Bacillus sp. Inoculation of $10^{2}$ cfu of Pseudomonas sp. gives rise to softening of onions. Pseudomonas sp. was identified as Pseudomonas gladioli by biochemical and physiological characteristics. P. gladioli is the first reported bacterium as a pathogen of onion in Korea. In low temperature, P. gladioli showed better growth and higher PGase activity than those of Bacillus sp. identified as Bacillus subtilis. And pH 9.0 is optimal pH for PGase activity of B. subtilis while that of P. gladioli is pH $5.0\∼6.0$ which is the acidity of onions. Taken together, P. gladioli may be a main pathogene of onion rot during the cold storage condition.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1085-1091
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• 2009

A phytase with high activity at low temperatures has great potential for feed applications, especially in aquaculture. Therefore, this study used a degenerate PCR and TAIL PCR to clone a phytase gene from Erwinia carotovora var. carotovota, the cause of soft rot of vegetables in the ground or during cold storage. The full-length 2.5-kb fragment included an open reading frame of 1,302 bp and encoded a putative phytase of 45.3 kDa with a 50% amino acid identity to the Klebsiella pneumoniae phytase. The phytase contained the active site RHGXRXP and HD sequence motifs that are typical of histidine acid phosphatases. The enzyme was expressed in Escherichia coli, purified, and displayed the following characteristics: a high catalytic activity at low temperatures (retaining over 24% activity at $5^{\circ}C$) and remarkably thermal lability (losing >96% activity after incubation at $60^{\circ}C$ for 2 min). The optimal phytase activity occurred at pH 5.5 and ${\sim}49^{\circ}C$, and the enzyme activity rapidly decreased above $40^{\circ}C$. When compared with mesophilic counterparts, the phytase not only exhibited a high activity at a low temperature, but also had a low $K_m$ and high $k_{cat}$. These temperature characteristics and kinetic parameters are consistent with low-temperature-active enzymes. To our knowledge, this would appear to be the first report of a low-temperature-active phytase and its heterogeneous expression.