• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.115-120
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• 1974

Secondary amines are known as one of the precursors of nitrosamines which are potent carcinogenic compounds of man and animals. Nitrosamines are formed when both secondary amines and nitrite are present. The nitrites are occurred naturally in vegetables, fruits and many others, and frequently used in fish product as a color fixative or a preservative. In this paper, to know the formation of nitrosamines in fish meat, the changes of dimethylamine (DMA) content during the heat treatment such as drying, roasting and fish cake processing are discussed. The results showed that generally DMA increased considerably during heat processing. During drying, DMA in cuttle fish increased 16 times higher, while in Alaska pollack doubled than the fresh. In the roasted mackerel, the DMA content appeared 6 times higher than the fresh, while 9 times higher in canning. In fish cake from yellow corvenia, DMA increased 4 times higher than the fresh. On the contrary diethylamine and diphenylamine were not found in this experiment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.5
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• pp.394-400
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• 1990

In the previous paper, we reported that the bacteriostatic effect of condensed phosphate. The present study was intended to observe influence of various environmental factors on the bacteriostatic effect of condensed phosphates in the laboratory media, in order to get the information on the possibility to use the phosphate as food preservative. Bacteriostatic effect of sodium polyphosphate was not reduced by the heating at 100 for 1 hour, but it was considerably decreased by heating at $121^{\circ}C$ for 15 min and the phosphate sensitivity of bacteria was increased by freezing and heating. On the other hand, the strong bacteriostatic activity of condensed phosphate was observed below pH 6.5 in nutrient broth culture, and the activity was decreased by the addition of $CaCl_2$, KCl and $MgSO_4$.

• Food Science and Preservation
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• v.14 no.5
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• pp.516-525
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• 2007

The effect on quality improvement of Chokochujang by the addition of green tea extract (GT) was evaluated on the basis of total cell numbers, pH, acidity, sugar content and sensory evaluation during its storage at $25^{\circ}C$ and $37^{\circ}C$ for 3 weeks. A dorminant strain was isolated from the Chokochujang and identified as Bacillus amyloliquefaciens ER282 based on the 16S rDNA sequence. The ethanol extract from GT was investigated for its antibacterial activity aid showed good activities enough to use for Chokochujang as a natural preservative. Growth of microorganisms was significantly inhibited by adding GT extract to Chokochujang but pH, acidity, sugar content and color was not much changed. Sensory evaluation and overall preference, however, was continuously declined as storage period increased, whereas the addtion of 3% GT extract could delay the quality loss of Chokochujang during storage at $25^{\circ}C$ and $37^{\circ}C$ for 3 weeks.

• Food Science and Preservation
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• v.14 no.5
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• pp.511-515
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• 2007

'Ooishiwase' plum (Prunus salicina L.) fruits were harvested at three pre-climacteric stages of ripeness (stages 1, 2, and 3) and treated with 1-methylcyclopropene (1-MCP, $1\;{\mu}L/L$) for 24 hours at $10^{\circ}C$ before storage to evaluate the effectiveness of 1-MCP in extending shelf-life at $10^{\circ}C$. Ethylene production and respiration rates were significantly lower after 1-MCP treatment compared to those of control fruit, throughout the entire storage period. Also 1-MCP delayed plum softening and color changes. However the chemical 1-MCP had no effect on fruit soluble solid content changes, the preservative 1-MCP is an effective tool for quality improvement in plums, and extension of shelf life of the fruit and plums can safely be harvested at stage 3 of ripening, at which time the most desirable organoleptic attributes have been developed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1115-1119
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• 2001

We prepared a functional red soybean curd (RS) from Ang-Khak according to various concentration (RS1 : red rice powder 0.1 g/10 mL, RS2: 0.2 g/10 mL, RS3: 0.3 g/10 mL, RS4: 0.4 g/10 mL, RS5: 0.5 g/10 mL, CS: control soybean curd). During the storage period of red soybean curd, pH, acidity, and microbial counts showed a minimum change in RS5. And in the case of color, all groups have slightly increased in yellowness except RS1. In the case of texture, hardness, gumminess, and springiness appeared to be increased for a few days and then fell down. As water drained out of soybean curd during storage at 1$0^{\circ}C$, it became so stiff and then rotten that the hardness of soybean curd increased in the early stage and then decreased after all. After a week, we could find a better preservative effect of RS than CS. Resultly, we need more efforts to prolong the shelf-life of soybean curd with applying the functionality of Ang-Khak.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.814-821
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• 2000

In order to investigate the possible use of omija extract as natural preservatives for nabak kimchi omija extract was tested for antioxidation and electron-donating ability and further more antimicrobial activites against lactic acid bacteria of nabak kimchi. The concentration of the test sample used were 0.5, 1.0, 1.5, 2.0%. Antioxidative activity measured the TBA value, when omija extract concentration % is higher the antioxidation effect were more evident with the increased omija extract concentrations, and showed a high electron donating activity more than 1.0%. As the result of isolated lactic acid bacteria from nabak kimchi the primary separation tool 117 strains, of these 4 strains which had excellent growth and a strong acid formation capability was selected the second time and Lactobacillus brevis, Lactococcus faecalis, Leuconostoc mesenteriodes, Lactobacillus palantarum were identified. After measuring the antimicrobial activity of the four lactid acid bacteris, except Lactobacillus brevis the other three bacteria showed strong antimicrobial activities. The results suggest the possible use of the omija extract as natural preservative for nabak kimchi.

• Food Science and Preservation
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• v.11 no.1
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• pp.17-21
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• 2004

The antimicrobial effect of mixed solution of botanical antimicrobial agent-citrus product (BAAC) and such a natural additive as aloe, ginseng or Prunus mume extract on the spoilage microorganisms of soybean sprouts were investigated by paper disk method. The mixture (BAAG) of BAAC and ginseng extract showed the remarkable antimicrobial activity in the result of the experiment. Therefore, we used BAAG as pre-soaking and cultivating solution of soybean sprouts. Total bacterial and Escherichia coli cell count of soybean sprouts pre-soaked and cultivated in the BAAG-diluted solution (50 ppm) showed 2.5 ${\times}$ 10 CFU/mL and 1.3 ${\times}$ 10 cfu/mL in comparison with 3.5 ${\times}$ 10$^3$ cfu/mL and 5.8 ${\times}$ 10$^3$ cfu/mL of the control, respectively. BAAG-treated soybean sprouts also showed no slimy brown product and undesirable odor characterized in the control. It was confirmed that BAAG could be a proper pre-soaking and cultivating solution of soybean sprouts.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.701-714
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• 2021

In this study, the microbial community succession and the protein hydrolysis of donkey meat during refrigerated (4℃) storage were investigated. 16S rDNA sequencing method was used to analyze the bacteria community structure and succession in the level of genome. Meanwhile, the volatile base nitrogen (TVB-N) was measured to evaluate the degradation level of protein. After sorting out the sequencing results, 1,274,604 clean data were obtained, which were clustered into 2,064 into operational taxonomic units (OTUs), annotated to 32 phyla and 527 genus. With the prolonging of storage time, the composition of microorganism changed greatly. At the same time, the diversity and richness of microorganism decreased and then increased. During the whole storage period, Proteobacteria was the dominant phyla, and the Photobacterium, Pseudompnas, and Acinetobacter were the dominant genus. According to correlation analysis, it was found that the abundance of these dominant bacteria was significantly positively correlated with the variation of TVB-N. And Pseudomonas might play an important role in the production of TVB-N during refrigerated storage of donkey meat. The predicted metabolic pathways, based on PICRUSt analysis, indicated that amino metabolism in refrigerated donkey meat was the main metabolic pathways. This study provides insight into the process involved in refrigerated donkey meat spoilage, which provides a foundation for the development of antibacterial preservative for donkey meat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.3
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• pp.41-46
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• 1982

To elucidate the preservative characteristics of chestnuts, three varieties, Ungi, Okkang and Chuckpa, were stored in cellar, polyethylen film packing, and box with or without $\gamma-irradiation$, and chemical compositions, rates of sprouting and rotting were determined during the period of storage. The chemical compositions of raw chestnuts were: moisture, 59 to 63%; total sugar, 28 to 29%; reducing sugar, 0.1 to 0.2%; crude fiber, 0.6 to 0.9%; crude protein, 3.5%; vitamin C, 27 to 28mg%; and tannin, 50 to 58mg%. Total sugar and vitamin C were decreased during the period of storage, and of reducing sugar and tannin were increased. The rates after 6 months of storage after three vareitia were; 93 to 100% by the cellar storage; 35 to 57% by the box storage without $\gamma-irradiation$ and 1 to 4% with $\gamma-irradiation$; and none by the polyethylene film packing. The sprouting rate in Chuckpa decreased markedly as compared with the other two varieties. The rotting rates when stored for 6 months were: 4 to 6% by the box storage without $\gamma-irradiation$ and 7 to 12% with $\gamma-irradiation$; 5 to 8% by the polyethylene film packing; and 30 to 54% by the cellar storage. The rotting rate in Chuckpa was lower than the other varieties during the period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.269-275
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• 1988

Inhibitory effects on bacterial growth by using lysozyme and mixtures of it with other antibacterial substances (sodium hexametaphosphate and sodium pyrophosphate) were investigated against the 7 kinds of hacterial strains isolated from putrefied surumi products. The growth inhibitory concentrations of lysozyme and lysozyme + sodium hexametaphosphate + sodium pyrophosphate against the bacteria were added to kamaboko, imitation crab meat and fried surumi, then viable cell count, pH and VBN were examined during the storage at $30^{\circ}C$ for 7 days. Lysozyme showed growth inhibitions against 6 of 7 isolates and the inhibition effect of mixture of antibacterial substances was multiplied against all the isolates compare with those of its individual use. Growth inhibitory effect of the substances on the bacteria was high in order of lysozyme + sodium pyrophosphate + sodium hexametaphosphate, lysozyme + sodium hexametaphosphate, lysozyme + sodium pyrophosphate and lysozyme. The most effective inhibitory concentration of mixture of the antibacterial substances in kamaboko and imitation crab meat was $0.05\%$ of lysozyme, $0.5\%$ of sodium pyrophosphate and $0.1\%$ sodium hexametaphosphate. But the bacterial growth was slightly inhibited in fried surumi even if the same concentration of the dipped mixture and the effect of the mixture was less than that of $0.2\%$ sorbic acid.