• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.79-84
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• 2002

Changes of microbiological and physicochemical characteristics of gamma irradiated Doenjang with low salt were studied. Samples were prepared by mixing the Doenjang and the Chungkukjang with 6% and 8% of salinity. The mixture was irradiated by gamma-ray with dose of 0, 5, 10, 20 kGy, and each sample was stored at $25^{\circ}C$ for 8 weeks. The results showed that the Bacillus cell was inactivated by $10^4-10^5\;cells/g$ with dose of 10 kGy, and yeast and Lactobacillus group were nearly eliminated by 10 kGy. The general quality of gamma irradiated low salt Doenjang, such as amino nitrogen, protease activity, and pH, were more stable than that of control during storage periods. The sensory evaluations showed that 8% (salt)-5 kGy and 6% (salt)-10 kGy irradiated samples were more acceptable than market purchased Doenjang. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of low salt Doenjang and suitable radiation dose was 5 kGy in 8% salted, and 10 kGy in 6% salted sample.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.21-33
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• 2013

The purpose of this study was to improve the production of Mozzarella cheese analogues manufactured using mixtures of soy milk and concentrated raw milk by performing ultrafiltration (UF) and to assess the quality of these cheeses during a 30-day storage period at $4^{\circ}C$, relative to that of Mozzarella cheese manufactured with the traditional method. The solid consistency of Mozzarella cheese analogue prepared from milk mixtures was lower than that of cheese manufactured from raw milk or soy milk and increased during storage, which is considered to be the result of decreasing water levels, as well as with increasing soy milk concentrations. In the Mozzarella cheese analogue generated using the milk mixtures, the fat content decreased with increase in the soy milk concentration, while it decreased during the storage period. Lactose levels were lowest in cheese composed of soy milk or raw milk and processed by UF, and decreased during storage in cheese produced using milk mixtures. In milk mixtures containing soy milk, the protein concentration increased with increasing amounts of raw milk and did not change during the storage period. The water-soluble nitrogen compound level was similar between cheeses and increased only slightly during storage. The amount of non-protein nitrogen compounds was higher in the cheese analogue than in the control cheese and tended to increase during storage. Analysis of the physicochemical traits of the Mozzarella cheese analogue yielded the following results: During storage, titratable acidity levels increased while pH tended to decrease. After analysis using electropherograms, it was classified as ${\alpha}$-, ${\beta}$-, or ${\kappa}$-casein. The results of rheometry tests showed that in the Mozzarella cheese analogue prepared from milk mixtures, with raw milk concentrated by UF, increases in concentration rate lead to lowered hardness, elasticity, cohesiveness, and brittleness. When cheese was produced from milk mixtures and concentrated by UF, meltability increased as the concentration rate increased, although to an extent that was less than that observed for the control cheese, and tended to increase during storage. Sensory evaluation showed that the analogue cheese was much better than the control cheese in terms of formation, appearance, and flavor.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.167-173
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• 2013

Dried fish products, such as seasoned cuttlefish, anchovy, and filefish, were analyzed to investigate the physicochemical quality and luminescence properties following gamma-irradiation. The overall color difference slightly increased in all irradiated samples, showing significant changes in Hunter's L, a, and b color values. Cuttlefish and filefish showed higher values in hydrophilic browning, whereas anchovy showed a higher value in lipophilic browning. The brown color intensity of filefish showed a dose-dependent increase. The thiobarbituric acid (TBA) value significantly increased in irradiated samples of cuttlefish and anchovy, which have relatively high lipid contents. Irradiated samples, except anchovy, were not suitable for screening using photostimulated luminescence (PSL) because only negative or intermediate values were observed. Thermoluminescence (TL) measurements were suitable for all fish samples, i.e., irradiation-specific glow curves were obtained, signal intensity increased, and the TL ratio fulfilled the criterion. There was no significant difference among the irradiated samples with regard to the sensory properties.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.254-262
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• 1997

new wild grape(NWG) cultivated in north Kyungki province in Korea, was tested by analyzing the proximate and physicochemical components of fresh fruit, the chemical components and sensory evaluation of wines made from the grape. NWG contained about 10% seed, and about 70% of juice. Total sugar content, total acidity and pH of the fruit juice were 17.50, 1.14 and 3.48%, respectively. Tartaric acid and malic acid contents of the NWG juice were 0.396 and 0.509%, respectively. Ethanol fermentation of the NWG by Saccharomyces cerevisiae Montrachet was rapid. The ethanol content, total acidity and pH of pink wine made from the NWG juice showed 11.88, 0.85 and 3.55%, respectively. Tartaric acid and malic acid contents of pink wine were 0.208 and 0.421%, respectively. Total anthocyanin content(A520) and color intensity(A520+A420) of pink wine were 5.46 and 9.39, showing greatly higher total anthocyanin content and color intensity than those of European red wines. Total phenol contents of NWG wine were 2, 300~3, 800mg/$\ell$. The pink wine made from the fruit juice was better than the red wine in their quality parameters and sensory scores.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.708-714
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• 2013

This study was performed to investigate the influence of age on the physicochemical properties of strip loin (m. longissimus lumborum), chuck tender (m. supraspinatus), and eye of round (m. semitendinosus) of Hanwoo cows. Hanwoo cows (n=126; 24-194 mon; live weight, 270-500 kg) were slaughtered and three muscles were obtained according to 3 age groups (G1, < 5 years old; G2, 6-8 years old; G3, > 9 years old). The chuck tender had significantly higher protein contents in G3 than in G1 or G2 (p<0.05). For strip loin and chuck tender, G1 had significantly higher intramuscular fat contents than G3 (p<0.05). The chuck tender had significantly higher $b^*$ (yellowness) values for G2 than for G1 (p<0.05). The three muscles had significantly higher cooking loss (%) and lower WHC (%) in G3 than in G1 or G2 (p<0.05). WBS values of strip loin were significantly higher in G3 than in the other groups (p<0.05). The three muscles had higher C18:1n9 in G1 than that in the other groups. The total content of saturated fatty acids was significantly higher in G3 than in G1 for all 3 muscles (p<0.05). Regarding free amino acid contents, G1 had significantly higher contents of threonine, alanine, valine, methionine, phenylalanine, leucine, and lysine in the strip loin than G2 or G3 (p<0.05). In conclusion, young cow beef were higher in the WHC, intramuscular fat and free amino acids contents, whereas old cow beef had higher cooking loss and WBS (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.923-928
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• 2016

To increase the consumption of head-type kimchi cabbage leaves as fresh food ingredients, the physicochemical composition was investigated depending on leaf parts. Kimchi cabbage leaves were divided into three portions, such as outer (L1), mid (L2), and inner (L3), and their proximate compositions were determined along with dietary fiber, free sugar, organic acid, free amino acid, and mineral contents. Contents of moisture, crude protein, and crude fat were highest in L1, whereas contents of crude ash and carbohydrate were highest in L3 (P<0.05). Calories ranged 24.5~26.5 kcal/100 g with no significant difference among leaf parts, and dietary fiber content of L1 was highest (P<0.05). Fructose, glucose, and sucrose contents were highest in L3 (P<0.05). Citric acid, malic acid, and succinic acid were detected, and contents of citric acid and malic acid were highest in L3, in contrast, succinic acid was highest in L1 (P<0.05). Glutamic acid, constituting over 30% of the total free amino acid contents, was highest in L3, whereas ${\gamma}-aminobutyric$ acid contents were highest in L1 (P<0.05). K, Na, Ca, and Mg were the major minerals in head-type kimchi cabbage, and their contents showed no significant differences (P<0.05). It can be proposed that marketing of head-type kimchi cabbage as a fresh-cut vegetable could be enhanced due to the different quality characteristics of its leaf parts.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.348-352
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• 2000

Four different Chinese cabbage cultivars were compared for their physicochemical quality characteristics including crude fiber, chlorophyll, firmness, hardness, sugar, and flavor at different parts of the cabbages. No significant difference in crude fiber content was observed among cultivars. Chlorophyll content in midrib was not significantly different among cultivars, however Chlorophyll content in leaf of 'Golden House' and 'Golden Spring' were greater than that of 'Alpine Summer' Firmness was the highest in 'Golden House' and 'Golden Spring' but hardness was not significantly different among cultivars. Sugar content was higher in midrib than in leaf. 'Golden Spring' a showed the highest sugar content in midrib. Glucose content was higher than the fructose content in leaf, but was opposite in midrib. Sensory evaluation showed that 'Golden House' and 'Golden Spring' were the best in yellowness, and 'Golden House' and 'Alpine Summer' were the best for their taste and aroma in midrib, however, no significant difference in texture was observed among cultivars.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.545-555
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• 2005

The physicochemical and microbial characteristics of Oiji prepared with dry salting method, which has been used industrially for industry, were investigated. Low salting and low storage temperature were employed:extremely low salting extremely low temperature; ESET $(5\%,\;0^{\circ}C)$, very low salting extremely low temperature;VSET $(10\%,\;0^{\circ}C)$, extremely low salting very low temperature; ESVT$(5\%,\;5^{\circ}C)$, low salting very low temperature; VSVT$(10\%,\;5^{\circ}C)$ and high salting low temperature;HSLT$(30\%,\;10^{\circ}C)$ for control. Acidity was lower, and pH was higher in VSET, in of which the fermentation pattern was similar with that of HSLT The time required to reach the optimum acidity ($0.3\%$ lactic acid) was longer delayed for VSET (168 days), than for compared to ESVT (51 days). During storage of Oiji, greenness (-a) as measured with of the Hunter color system wasshowed the highest in VSET, and the lowest while in ESVT, the lowest. Total microbial and lactic acid bacteria counts number were the lowest in HSLT and VSET and were the lowest than in other groups, while the highest in ESVT. Yeast was not detected in HSLT, but was the highest while in VSVT. E coli coliform and listeria were detected in the $5\%$ salting groups, although Salmonella was not detected in any of the all groups. Texture profile analysis demonstrated exhibited that fracturability and hardness were highest in HSLT and VSET, compared to the other groups. Scores of over-all preference for ESVT and HSLT were higher atwith 6.3 and 6.2, respectively, compared to the other products. Based on these results, lower saltiness less than $10\%$ and lower storage temperature (less than $5^{\circ}C$) condition was optimum for maximizing the better for good quality of industrial Oiji preparation in industry.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.42-46
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• 2007

We evaluated the microbial safety and quality characteristics of Korean slice beef jerky, and investigated these properties over 28-day and 90-day storage periods at room temperature ($25^{\circ}C$) and elevated temperature ($35^{\circ}C$). After microbial counts of all samples, mesophilic bacteria were detected at 1.23 Log CFU/g at day 0. Counts of mesophilic bacteria did not change significantly in all samples, and coliforms and Bacillus cereus were not detected in all samples during storage at either $25^{\circ}C$ or $35^{\circ}C$. TBA values, Aw, and pH were investigated. The Aw of korean slice beef jerky stored at room temperature was 0.71 at day 0, and was reduced to 0.61 after 90 days. The TBA value increased as storage time increased, and its TBA value was 0.48 after 90 days of storage. The pH of all samples did not change significantly. At $35^{\circ}C$ storage, TBA values, Aw, pH were not significantly different than those stored at $25^{\circ}C$. Also, the sensory properties of all samples were not significantly different between two storage temperatures. In conclusion, these results suggest Koran slice beef jerky ould be used as basic study for development of the commercial beef jerky.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.17-23
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• 2018

The objective of this study was to compare physicochemical, microbial, and antioxidant properties of domestic and imported wheat kernels for bread making. Two domestic (JK1, 2) and three imported (ND, DNS, and CWRS) kernels were compared. Domestic kernels had higher moisture contents, and lower ash and protein contents (p<0.05). In grain characteristics, JK1 had 13.62% of damaged kernels, which was the highest among the samples (p<0.05). JK2 was similar to imported kernels in the ratio of sound kernels, foreign materials, and damaged kernels. Kernel size of JK1, 2 was larger than the imported kernels; therefore, kernels area and perimeter were higher by the image analyzer. Domestic kernels hid lower total aerobic counts the imported kernels (p<0.05). Domestic kernels and DNS had no yeast, while NS and CWRS had yeast in kernels. DNS (3.08 mg gallic acid equivalent (GAE)/g) had the highest total polyphenol content (TPC), followed by JK1 (2.81 mg GAE/g). JK2 had the lowest amount of TPC as 2.26 mg GAE/g. Total flavonoid content (TFC) was the highest in DNS as 0.44 mg catechin equivalent (CE)/g and JK2 was the lowest as 0.12 mg CE/g. Domestic wheat kernels had lower protein content and lightness than the imported wheat kernels so that flour from domestic wheat kernels may have lower quality for baking.