• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.1045-1051
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• 2021

Eighty-nine different types of commercially salt-fermented fishery products comprising various raw materials were analyzed for total aerobic bacteria, number of coliform bacteria, fecal coliform, and Escherichia coli. The food-poisoning bacterial content of the samples was investigated using next-generation sequencing. The mean mass of total aerobic bacteria in Jeotgal was 6-1.8×10⁹ CFU/g, and that in Aekjeot and Sikhae was 4-2.2×10⁵ CFU/mL and 1.9×10⁵-8.4×10⁸ CFU/g, respectively. Coliform bacteria were detected in 9 (28.1%) of 32 Jeotgal samples; 15 (46.8%) of 32 seasonal Jeotgal samples; and in 5 (55.5%) of 9 Sikhae samples. Fecal coliform and E. coli were not detected in 86 of the 89 samples. Yersinia enterocolitica was detected only in Galchi jeot (salt-fermented hairtail) (1 type) and not in other Jeotgal samples. These results contribute to our knowledge regarding the bacterial stability of salt-fermented fishery products.

• Food Science and Preservation
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• v.16 no.4
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• pp.567-572
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• 2009

We evaluated the microbiological quality of a facility in which freshly cut onions were prepared. The total plate counts on walls, equipment, and raw materials were ND (not detected) to $10^1$ CFU/100 $cm^2$, $10^0{\sim}10^3$ CFU/100 $cm^2$, and $10^3{\sim}10^4$ CFU/g, respectively. No coliforms were detected on walls however, coliforms were detected at concentrations of ND to $10^3$ CFU/100 $cm^2$ and $10^3{\sim}10^4$ CFU/g on equipment and raw materials, respectively. The total plate counts for falling and floating bacteria in the processing plant were ND to $10^0$CFU/plate and $10^1{\sim}10^2$ $CFU/m^3$, respectively. Pathogenic microorganisms such as Escherichia coli, Salmonella spp, Staphylococcus aureus, and Listeria monocytogenes were not detected on walls, equipment, or raw materials. Overall, the results of the study indicate that hygiene control at the fresh-cut processing plant should be improved.

• Journal of Microbiology and Biotechnology
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• v.34 no.3
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• pp.622-633
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• 2024

For quality standardization, the application of functional lactic acid bacteria (LAB) as starter cultures for food fermentation is a well-known method in the fermented food industry. This study assessed the effect of adding a non-thermally microbial inactivated starter culture to kimchi, a traditional Korean food, in standardizing its quality. In this study, pretreatment based on sterilization processes, namely, slightly acidic electrolyzed water (SAEW) disinfection and ultraviolet C light-emitting diode (UVC-LED) of raw and subsidiary kimchi materials were used to reduce the initial microorganisms in them, thereby increasing the efficiency and value of the kimchi LAB starter during fermentation. Pretreatment sterilization effectively suppressed microorganisms that threatened the sanitary value and quality of kimchi. In addition, pretreatment based on sterilization effectively reduced the number of initial microbial colonies in kimchi, creating an environment in which kimchi LAB starters could settle or dominate, compared to non-sterilized kimchi. These differences in the initial microbial composition following the sterilization process and the addition of kimchi LAB starters led to differences in the metabolites that positively affect the taste and flavor of kimchi. The combined processing technology used in our study, that is, pre-sterilization and LAB addition, may be a powerful approach for kimchi quality standardization.

• The Korean Journal of Food & Health Convergence
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• v.10 no.3
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• pp.19-22
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• 2024

The field of synthetic biology has emerged in response to the ongoing progress in the life sciences. Advances have been made in medicine, farming, eating, making materials, and more. Synthetic biology is the exploration of using living organisms to create new organisms. By manipulating specific genes to express targeted proteins, proteins can be created that are both productive and cost-effective. Solid-phase extraction (SPE) and liquid-liquid extraction (LLE) are employed for protein separation during the production process involving microorganisms. This study centers on Scanning Probe Microscopy (SPM) to showcase its utility in the food industry and food management. SPE is predominantly utilized as a pretreatment method to eliminate impurities from samples. In comparison to LLE, this method presents benefits such as decreased time and labor requirements, streamlined solvent extraction, automation capabilities, and compatibility with various other analytical instruments. Anion exchange chromatography (AEC) utilizes a similar methodology. Pharmaceutical companies utilize these technologies to improve the purity of biopharmaceuticals, thereby guaranteeing their quality. Used in the food and beverage industry to test chemical properties of raw materials and finished products. This exemplifies the potential of these technologies to enhance industrial development and broaden the scope of applications in synthetic biology.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.101-106
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• 2001

Alpha-amylase and glucoamylase activities were higher in koji with 40% water than that with 30 and 50% water, and A. oryzae exhibited very high alpha-amylase and glucoamylase activities compared to A. sojae and A. niger. Acidic, neutral and alkaline protease activities also showed higher activities in koji prepared with flour, Korean wheat powder and soybean powder with 40% water based on the weight of the sample. Alpha-amylase, acidic, neutral and alkaline protease activities of all the koji samples according to incubation periods increased until 3~4 days of incubation and maintained nearly the same level or slightly decreased after 5 days of incubation. The protease activities of A. oryzae and A. sojae showed nearly the same trend regardless of differences in substrate conditions and koji materials, but those of A. niger showed a lower activity than those of A. oryzae and A. sojae. These results suggest that the preparation of koji is possible with Korean wheat powder and soybean powder and A. sojae can be utilized as a new strain for fermented foods using soybean as the main materials to increase functional properties and produce products having a new taste and flavor.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.344-349
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• 2005

Two different NokJoongTangs were prepared by boiling antler and various oriental medicinal materials. The phenolic contents and free radical scavenging effects against DPPH(1,1-diphenyl-2-picrylhydrazyl) radical and hydroxyl radical of the NokJoongTangs which are used as the health supplement foods, were investigated. NokJoongTang-II prepared dried antler with various oriental medicinal materials, had higher phenolic content than that of NokJoongTang-I prepared 1mm raw antler with the same materials. In addition, NokJoongTang-II exhibited higher scavenging activities than these of NokJoongTang-I against DPPH radical and hydroxyl radical. These result indicate that free radical scavenging activity of NokJoongTang showed a difference by using raw and dry antler for NokJoongTang preparation, and that the findings also show a positive correlation between radical scavenging activity and total phenolic contents.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.1057-1062
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• 2016

Kimchi is a traditional Korean fermented vegetable food, the production of which involves brining of Korean cabbage, blending with various other ingredients (red pepper powder, garlic, ginger, salt-pickled seafood, etc.), and fermentation. Recently, kimchi has also become popular in the Western world because of its unique taste and beneficial properties such as antioxidant and antimutagenic activities, which are derived from the various raw materials and secondary metabolites of the fermentative microorganisms used during production. Despite these useful activities, analysis of the microbial community present in kimchi has received relatively little attention. The objective of this study was to evaluate the bacterial community structure from the raw materials, additives, and final kimchi product using the culture-independent method. Specifically, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the 16S rRNA partial sequences of the microflora. One primer set for bacteria, 341F^GC-518R, reliably produced amplicons from kimchi and its raw materials, and these bands were clearly separated on a 35-65% denaturing gradient gel. Overall, 117 16S rRNA fragments were identified by PCR-DGGE analysis. Pediococcus pentosaceus, Leuconostoc citreum, Leuconostoc gelidum, and Leuconostoc mesenteroides were the dominant bacteria in kimchi. The other strains identified were Tetragenococcus, Pseudomonas, Weissella, and uncultured bacterium. Comprehensive analysis of these microorganisms could provide a more detailed understanding of the biologically active components of kimchi and help improve its quality. PCR-DGGE analysis can be successfully applied to a fermented food to detect unculturable or other species.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.177-182
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• 2013

This study was conducted to evaluate the effect of gamma irradiation on the microbial populations of dried raw materials (9 products) and Saengsik powder. The samples were gammairradiated at doses of 2, 4, 6 and 8 kGy and the microbiological populations were evaluated. The total numbers of bacteria and Bacillus cereus in non-irradiated dried-raw materials for Saengsik powder was 1.3~3.4 and $1.7{\sim}2.4log\;CFU\;g^{-1}$. However, gamma irradiation reduced the microbiological populations in all samples, and Saengsik powder were sterilized at more than 6 kGy. Moreover, Clostridium perfringens were not observed in all samples within detection limit (<$1log\;CFU\;g^{-1}$). Therefore, the results of this study suggest that gamma irradiation at 6 kGy is sufficient to sterilize Saengsik powder, and thus, irradiated Saengsik powder at 6 kGy fulfills the microbiological requirements for sterilized food.

• Journal of Food Hygiene and Safety
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• v.24 no.3
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• pp.226-231
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• 2009

The aim of this study was to determine exposure assessment of pathogenic bacteria in edible ices by using the monitoring data from the previous study. According to the results of exposure assessment of edible ices contaminated with S. aureus, the contamination level of S. aureus in raw materials was higher than other foodborne pathogens, and the contamination level of S. aureus in mixed samples increased much before sterilization. The most significant reduction in contamination level was observed in mixed samples after sterilization, thus, the contamination levels in frozen final products was less than that of raw materials. Overall, the possibility for the infection of foodborne bacteria from the intake of edible ices per person per day was ranged from minimum $5.89{\times}10^{-7}$ to maximum $5.01{\tims}10^{-5}$. For more realistic estimates, consumption of edible ices and dose-response model must be studied further.

• Journal of Nutrition and Health
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• v.37 no.8
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• pp.722-731
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• 2004

The objective of this study was to evaluate the microbiological quality of non-heat-processed foods for implementation of a HACCP (Hazard Analysis and Critical Control Point) system in day-care center foodservice operations. The evaluating points were microbial assessment of foods, utensils, and employee's hands during preparation, cooking, and serving. The temperature of non-heated food being served was also measured. Microbiological quality was assessed using 3 M Petrifilm/syp TM/ to measure total plate count and coliforms for food and utensils and Staphylococcus aureus for hands in five Gumi day-care centers. Results showed low microbiological quality of non-heated foods. This was probably due to contaminated raw ingredients and cross-contamination that occurred during preparation and cooking (e.g., unsatisfactory washing and disinfection of raw materials and utensils). These results suggest that it is essential to educate employees on good personal hygiene (hand washing) , prevention of cross-contamination through use of properly washed and sanitized utensils, and proper washing and disinfection of raw vegetables. Establishing Sanitation Standard Operating Procedures (SSOPs) are an essential part of any RACCP system in day-care center foodservice operations.