• Food Science of Animal Resources
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• v.30 no.2
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• pp.298-304
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• 2010

This study was performed to evaluate functional and textural properties of low-salt pork meat products treated with transglutaminase (TG) using sodium polyphosphate (STPP) and sodium pyrophosphate (SPP). In experiment 1, lightness and yellowness decreased (p>0.05), but moisture content and cooking yield (%) increased with increased salt level (p<0.05). Based on these results, at least 1.0% salt was required to manufacture comminuted pork meat without quality defects. The effect of STPP and SPP with TG in low-salt (1%) pork comminuted shoulder meat products was evaluated in experiment 2. pH values increased with the addition of phosphate (p<0.05), with pH values in treatments containing TG and PP alone or in combination being higher than those with STPP alone (p<0.05). Cooking yield of treatments with TG and phosphates was higher than those without phosphates, but lower than CTL (1.5% salt and 0.4% STPP; p<0.05). Springiness of pork comminuted meat containing SPP was higher than those of CTL (p<0.05). These results indicate that low-salt meat products can be produced by the combination of TG and phosphate either alone or in combination to maintain cooking yield and textural properties.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.334-339
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• 2009

This study was carried out to determine the effects of olive-oil prepared tomato powder (OPTP) and lycopene on seasoned raw pork. 1.5% OPTP was added in T1 and 3.0% in T2; and 0.03% refining lycopene was added in T3. While in storage, pH values of the treated samples were lower (p<0.05) than those of the control samples. Upon increasing storage, salinity values of OPTP samples increased as well, however, the values of T3 did not change. There were significantly higher TBARS values observed in the OPTP samples compared to control, but no significant difference between T3 and the control samples in TBARS values during storage. VBN values of T2 samples were lower than that of other samples at Day 3 and Day 6 of storage. At Day 9 however, the VBN values of T1 and T2 were significantly higher than those of the control and T3. There was no significant difference between the control and the treated samples in the total plate counts. There were relatively higher redness, yellowness and chromatic values observed in the treated samples than in control. In sensory evaluation, there was no significant difference between the control and the treated samples in color, tenderness, juiciness and overall acceptability.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.313-320
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• 2010

The purpose of this study was to evaluate the freshness of chicken meat during 19 d of storage at $4^{\circ}C$ using a portable electronic nose. The portable system consisted of six different metal oxide sensors and a moisture sensor. Determination of volatile compounds with gas chromatography-mass spectrometry, total bacterial count (TBC), and 2-thiobarbituric acid reactive substances (TBARS) monitored the quality change of the samples. These results were compared with the results measured by the electronic nose system. TBC and TBARS measurements could be separated into five groups and seven groups, respectively, among ten groups. According to principal component analysis and linear discriminant analysis with the signals of the portable electronic nose, the sample groups could be clearly separated into eight groups and nine groups, respectively, among ten groups. The portable electronic nose demonstrated potential for evaluating freshness of stored chicken.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.565-569
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• 2002

This study was carried out to estimate the effects of preservatives (alcohol, adipic acid) and heat treatment $(40^{\circ}C,\;60^{\circ}C)$ for the prolongation of shelf-life on low-salt Kimchi. Low-salt Kimchi was prepared with salt replacements (NaCl 50%, KCl 36%, $MgSO_4$ 10%, $CaSO_4$ 3%, glutamic acid 0.2%). Chemical characteristics and microbiological parameters were monitored during fermentation at $20^{\circ}C$. When three kinds of preservative which were alcohol 2.0%, adipic acid 0.1% and their mixture were added to low-salt Kimchi, shelf-life of them were prolonged. To extend the shelf-life of low-salt Kimchi, when the heat treatment at $40^{\circ}C$ and $60^{\circ}C$ were tried, heat treatment at $60^{\circ}C$ was superior than at $40^{\circ}C$. In sensory evaluation of low-salt Kimchi, the control was showed the best quality in the overall acceptability. And low-salt Kimchi treated at $40^{\circ}C$ showed the most similar characteristics to the control Kimchi.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.625-630
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• 2002

Raw pine-mushrooms (Tricholoma matsutake Sing.) of four grades and those frozen were analyzed for proximate composition, smell pattern, volatile flavor compounds, and sensory evaluation. Proximate compositions of raw pine-mushrooms (A-C, regular grade) were $89.48{\sim}90.77%$ moisture, 6.81% ash excluding D (below regular grade) sample, $2.24{\sim}2.52%$ crude lipid, and $16.19{\sim}20.01%$ crude protein. Proximate compositions of frozen pine-mushrooms preserved for 6 months at -20 and $-70^{\circ}C$ showed no difference compared with raw pine-mushrooms. Results of smell pattern and multidimensional analysis revealed raw pine-mushrooms showed no differences among samples, but frozen pine-mushrooms differed significantly depending on the grade. Volatile flavor compounds of pine-mushrooms were analyzed using a purge and trap method with GC/MSD. Twenty-nine volatile compounds were identified, among which alcohols such as 1-octen-3-ol, 2-octen-1-ol, 3-methyl-butanol, and n-octanol were commonly found in all pine-mushroom samples. In sensory attributes, raw pine-mushrooms were not significantly different at 5% level, and sample D of frozen pine-mushrooms scored lower than samples $A{\sim}C$.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.387-395
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• 2000

The rheological properties of wheat flour dough and qualities of bread prepared with 0, 10, and 20% of dietary fiber slurry extracted and purified from ascidian (Halocynthia roretzi) tunic were investigated. Water absorption of the dough increased with the increase of dietary fiber slurry. Both arrival and development time of the dough with 10 and 20% dietary fiber slurry added were shorter than those of the control. An increase in the added amount of the dietary fiber slurry resulted in an increase of weakness. The dough's extensibility and resistance to extension were decreased, and the ratio of resistance to extensibility (R/E) decreased with the increase in the dietary fiber slurry. The maximum viscosity gradually decreased with the increase in the amount of dietary fiber slurry, while the temperature of gelatinization was not changed. Both loaf and specific volume of bread were slightly decreased with an increase in the amount of dietary fiber slurry. Overall preference scores by sensory evaluation and the quality characteristics of the bread with up to 20% dietary fiber slurry added was not significantly different from those of the control(p<0.05). The results indicated that the addition of the dietary fiber from ascidian tunic retarded staling and improved the shelf-life of the bread by enhancing the water holding capacity.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1271-1277
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• 2000

The extracts from tomatoes, apples, carrots, mallows, watercreses+pine needles, Angelica keiskei Koiz, jujubes and lemons were selected and mixed at the ratio of 3 : 3 : 3 : 1/2 : 1/2 : 1/2 : 1/2 : 1/5 on the basis of sensory evaluation. The mixed extracts were divided into three lots and treated as follows. The first lot was heated for 15 sec at $96^{\circ}C$ without centrifugation and filtration, the second filtered through a ultramembrane filter. For the third one, the ultrafiltrate combined with autoclaved retentates on the membrane filter and the previous centrifugal precipitation. The mixed juices were stored in the glass bottles with atmosphere or in film package with nitrogen gas. And then they were stored at $4^{\circ}$ and $20^{\circ}C$. During storage the treated juices showed $pH\;4.07{\sim}4.10$, titratable acidity $66.35{\sim}84.08$, soluble solid $7{\sim}9^{\circ}Brix$, reducing sugar $5.42{\sim}6.97%$, glucose $1.96{\sim}2.30%$ and fructose $3.46{\sim}4.14%$. The ultrafiltered juices showed yellow color, different from orange color of other treatment lots. Peroxidase activity and microbial population were inhibited by thermal treatment and ultrafiltration. The browning effects of the mixed juice of fruits and vegetables during storage were caused by ascorbic acid oxidation and non-enzymatic browning reaction, which could be reduced by change and packing with nitrogen gas instead of atmosphere inside bottles.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.45-50
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• 1994

Conventional Doenjang, three kinds of Improved Doenjang(A; koji: soybean: salt=53: 100: 33, B; koji: soybean: salt=100: 100: 40, C; koji: soybean: salt= 200: 100: 40) prepared with different ratio of koji and salt were made to study the changes in the general contents, characteristics bitter peptides, correlations between bitterness and overall eating quality. 1. Total nitrogen contents increased a little, and amino nitrogen contents in all samples increase markedly. Especially, Amino nitrogen contents of conventrional Doenjang increased more than others. Reducing sugars of doenjang prepared with Asp. oryzae were higher than conventional Doenjang and increased throughout the aging period and Doenjang prepared with Asp. oryzae were more acidic. 2. To characterize bitter peptides in fermented Doenjang, peptides were extracted with 2: 1(v/v) chloroform-methanol and separated by Gel chromato-graphy with Sephadex and TLC. After Gel chromatography and TLC, each fraction examined presence of bitterness and evaluated intensity of bitterness. Amino acid composition of the fractions showing bitter tastes were as follows. Conv. peak 1-1 Trp-(Asp, Arg, Thr, Ser, Glu, Pro)-Phe Imp. A peak 1 Trp-(Glu, Val, Arg, lie)-Phe Imp. B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp. Imp. C peak 1-2 Trp-(Try, Thr, Glu, Pro, Gly)-Phe 3. Sensory evaluation revealed that correlation coefficient between bitterness and overall eating guality was not high.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.280-288
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• 2016

This study proposes improved welding tools for magnesium alloys. Two types of tools were used for friction stir welding (FSW). The effect of the welding tools on the FSW joints was investigated with a fixed welding speed of 200mm/min and various rotation speeds of 400 to 800 rpm. After FSW, the joints were cross-sectioned perpendicular to the welding direction to investigate the defects. A tensile test and Vickers hardness test were conducted to identity the mechanical properties of the joints. Defects were observed when the rotation speed was 400 rpm, regardless of the welding tool, and the amount of defects tended to decrease with increases in rotational speed. Defect-free welds were obtained when the rotation speed was 800 rpm. The best weld quality was acquired using the C type welding tool. The rotation speed of 800 rpm and welding speed of 200 mm/min produced the best joining properties. The ultimate tensile strength, yield strength, and elongation of the welded region were 90.0%, 69.1%, and 83.2% those of the base metal, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.224-234
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• 2017

This paper compares the realities of the salary Peak Policy's status and management processes in Korea and Japan, with the aim of determining the development direction for Korea's salary Peak Policy's. Unlike Japan, which successfully achieved close cooperation between government, firms and workers in implementing the Retirement Age Extension Type salary Peak Policy, Korea experienced many problems due to lack of preparation. In order to rationally develop the salary Peak Policy, the government, firms, and workers must cooperate to increase the policy's efficiency via the following steps. First, gradually increase the proportion of retirement age extension. Second, career development that takes into account the various employment types, flexible working hours and aged workers. Third, development of training programs for senior citizen workers, as well as increasing support for changing of jobs and startups. Fourth, expansion of re-employment after retirement age and ways to make use of the skilled labor. Fifth, increasing work efficiency through bonuses and work evaluation that is specialized for aged workers. This paper argues that such measures are necessary for the co-existence of firms and workers, as well as for improving employment stability and labor market flexibility.