• Food Science of Animal Resources
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• v.40 no.1
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• pp.11-20
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• 2020

The intent of this study was to scrutinize the consequence of salt type [sundried salt, refined salt, baked salt, or nitrate pickling salt (NP)] on the physicochemical and microbiological features of salami formulated by soaking with Aspergillus spp. before ripening. The effects of nitrate-free salts added were not significant. Nitrate pickling salt samples were significantly higher in protein level, whereas those were lower in fat level during ripening (p<0.05). The pH of salamis treated with NP was higher than that of other salt treatments, while weight losses of those was lower (p<0.05). During the ripening and drying, NP produced lower extent of volatile basic nitrogen and lipid oxidation than those with other salts (p<0.05). The total aerobic population counts of NP samples revealed lower than that of other samples over the ripening time. The addition of NP in salamis produced redder sausages. The salamis containing NP found to be better physicochemical and microbiological quality attributes than the other salt types.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1060-1067
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• 2006

This study was undertaken to determine the effect of reservoirs on water quality and the distribution of pathogenic and indicator bacteria in a drinking water distribution system (total length 14km). Raw water, disinfected water, and water samples from the distribution system were subjected to physicochemical and microbiological analyses. Most factors encountered at each season included residual chloride, nitrate, turbidity, and phosphorus for heterotrophic bacterial distribution, and hardness, heterotrophic bacteria, sampling site, and DOC (dissolved organic carbon) for bacteria on selective media. No Salmonella or Shigella spp. were detected, but many colonies of opportunistic pathogens were found. Comparing tap water samples taken at similar distances from the water treatment plant, samples that had passed through a reservoir had a higher concentration of heterotrophic bacteria, and a higher rate of colony formation with 10 times as many bacteria on selective media. Based on the results with m-Endo agar, the water in reservoirs appeared safe; however, coliforms and opportunistic pathogenic bacteria such as Pseudomonas aeruginosa were identified on other selective media. This study illustrates that storage reservoirs in the drinking water distribution system have low microbiological water quality by opportunistic pathogens, and therefore, water quality must be controlled.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.512-519
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• 2023

Pacific oysters Crassostrea gigas are a popular shellfish in the Republic of Korea. However, due to their abundant moisture and nutrient content, oysters are susceptible to microbiological growth and biochemical changes, which lead to quality degradation. Therefore, the present study aimed to investigate the effectiveness of modified atmosphere packaging (MAP) in maintaining the quality of raw oysters during storage. Microbiological and physicochemical parameters such as pH, glycogen content, soluble protein, turbidity, and volatile basic nitrogen (VBN) were analyzed for oysters stored under various gas compositions and storage periods. The results showed that there was no significant increase in viable cell count in MAP oysters after six days in MAP oysters. Moreover, the physicochemical quality of non-MAP oysters deteriorated rapidly, whereas the quality of MAP oysters were maintained during storage. This study suggests that MAP can be an effective technique for maintaining the freshness of raw oysters during distribution and storage, and may also be useful for extending the shelf-life and maintaining the quality of other seafood products.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.712-719
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• 2018

This study was carried out to obtain basic data on Korean traditional Meju collected from 18 regions (TM1~TM18) in Korea and to define and control quality. The shape of Meju was mostly rectangular and the weight was 0.84~2.04 kg. The physicochemical analysis showed: pH, 5.31~8.21; total acidity, 0.91~2.74%; moisture content, 4.79~42.16%; and soluble protein content, 41.37~23.48%. Hunter color values for L (lightness), a (redness), and b (yellowness) ranged from 39.07~67.92, 3.57~8.87, and 7.48~20.67, respectively. The amino nitrogen contents of all samples were in the range of 257.29 to 839.58 mg% and TM13 showed the highest content (839.58 mg%). Total viable cells, yeast and mold counts of Meju were 8.43~5.91 log CFU/g, 2.48~5.19 log CFU/g, and 3.42~7.48 log CFU/g, respectively. Based on the results, it is proposed that quality standards and management of Meju fermentation conditions and information about different varieties of soybeans used should be made available.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.680-684
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• 2009

The effects of garlic and onion on the microbiological and physicochemical properties of irradiated ground beef patties were evaluated. Ground beef was mixed with 0.5%(w/w) minced garlic or 2.5%(w/w) minced onion, vacuum-packed in oxygen-impermeable nylon/PE bags and then electron beam-irradiated at 2.5 kGy. All samples were kept at $4^{\circ}C$ for 8 d. Irradiation resulted in a 2-log CFU/g reduction in both aerobic and coliform bacteria. The microbial counts gradually increased during storage, but those in beef that contained garlic or onion were 1-log CFU/g lower than those of the control samples after 8 d of storage. The pH value decreased during storage in all meat samples, but this decrease was greater in non-irradiated beef than in irradiated beef. The lipid oxidation, volatile basic nitrogen content and Hunter color values of raw patties were generally not affected by irradiation or the addition of garlic and onion. Sensory evaluation of cooked patties showed that the off-odor was less pronounced in samples that contained added garlic or onion than in control samples, and that the overall acceptability of beef formulated with garlic was the highest. Overall, the results of this study indicate that the addition of garlic or onion in combination with irradiation treatment enhanced the microbial quality and improved the sensory quality of irradiated ground beef.

• Preventive Nutrition and Food Science
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• v.2 no.2
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• pp.89-95
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• 1997

The comparative effects of gamma irradiation an ozone treatment on the microbiological and physicochemical qualities were investigated for the improvement of hygienic quality of aloe powder and bee pollen. Gamma irradiation at 7.5~10kGy could reduce total aerobic bacteria, molds and coliforms below detection levels, but ozone treatment up to 18 ppm for 8hr was not sufficient to eliminate the microorganisms from aloe powder and bee pollen. The physicochemical properties such as fatty acid an amino acid compositions, mineral content, TBA value, barbaloin and pigment contents were not significantly changed by gamma irradiation, whereas ozone treatment caused significant changes in fatty acid composition, lipid oxidation and destruction of barbaloin and natural pigments.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.722-729
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• 2010

The aim of this study was to evaluate the physico-chemical, sensory, and microbiological properties of ready-to-eat Korean traditional seasoned beef ribs ("galbi-jjim") prepared by sous-vide/cookchill technology during storage at three different temperatures (4, 10, and $20^{\circ}C$). Beef short ribs marinated in soy sauce for 24 h at $3^{\circ}C$ were packed with vegetables under vacuum. Vacuum-packed beef ribs mixed with vegetables were heated at $90^{\circ}C$ for 90 min in a water bath, and then immediately chilled below $3^{\circ}C$ within 120 min in an ice slurry. Physicochemical (pH, water activity, TBARS, $L^*a^*b^*$ color, and texture profile), sensory (appearance, odor, flavor, texture, and acceptance) and microbiological (Coliform, Escherichia coli, food-borne pathogenic bacteria) properties of the samples were determined during storage at different temperatures. Results showed that pH, $a_w$, and sensory evaluation of products were not affected in any consistent way as a function of either storage duration or temperature. Coliform, E. coli and food-borne pathogens were not detected during storage at any temperature. However, TBARS significantly increased during storage period (p<0.05). Based on TBARS values, SV/CC "galbi-jjim" can be stored for 15 d, 12 d and 1 d at 4, 10 and $20^{\circ}C$, respectively.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.45-54
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• 2002

Packaged Backsulgi cooked by steam/convection oven and then rapidly chilled was examined by research of microbiological test and sensory evaluation while storing them at the temperatures of 3$^{\circ}C$ and 3$0^{\circ}C$ for 0, 2, 4, 6, 10 days . The pH and reducing sugar content were seemed to change little at 3$^{\circ}C$. However the pH was rapidly reduced until 4 days and then decreased a little at 3$0^{\circ}C$, the reducing sugar content was inclosed little by little. In the microbiological test, any microbial growth in total aerobic, psychrophilic, anaerobic, spore forming bacteria, yeast and molds was not observed until 10 days at 3$^{\circ}C$, but microbial changes of aerobic, psychrophilic and anaerobic bacteria increased to 6 logCFU/g until 10 days at 3$0^{\circ}C$. However microbial changes of them decreased from 6 logCFU/g to 5 logCFU/g. As a result of the sensory evaluation, appearance, taste, color, softness, chewiness and overall Quality were significantly decreased during storage times(p<0.05), but scores of taste and overall quality on 6th days were 7.38${\pm}$1.06, 7.00${\pm}$0.93. Therefore we concluded that there was no problem about stability of storage 6 days at 3$^{\circ}C$.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.1
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• pp.11-19
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• 2022

This study provided basic data for the commercialization of healthy functional beverages by examining the physicochemical characteristics, nutrient content, and microbiological safety of onion peel beverage. The total acid of onion peel beverage was 0.12 mg/g and the pH was 6.07. According to the storage period, the total acid decreased and the pH increased in all temperature ranges(25℃, 35℃, and 45℃). After 30 days of storage, it showed 0.06 mg/g in all temperature sections and maintained the pH 7 range. The total phenol content, which is a nutritional component of onion peel beverage, was 0.93 mg/g, flavonoid content was 0.25 mg/g, and quercetin content was 0.17 mg/g. The flavonoid content decreased according to the storage period, and in the case of storage temperature of 25℃, it contained 50% content up to 120 days of storage, but in the case of 35℃ and 45℃, it had a flavonoid content up to 90 days and 30 days, respectively. In the case of quercetin, a residual rate of about 50% was shown for 150 days of storage at 25℃ and 35℃. In the case of 45℃, it decreased to 35% at 30 days of storage. On the other hand, onion peel beverage maintained a viable cell count of less than 5 CFU/mL for 150 days of storage, and no coliform group was detected. As a result of analyzing the quality characteristics of onion peel beverage according to storage period, quality stability was confirmed in physicochemical characteristics and microbiological safety. Research on changes in biological activity according to low-temperature distribution or storage period is necessary.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.291-298
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• 2010

We has been researched physicochemical, sensory and microbiological characteristics of salt-fermented shrimps after making them with different kinds of salts such as domestic or imported and purified or solar salt. Physicochemical characteristics of salt-fermented shrimps on color, salinity and pH which was made by 6 kinds of salt did not show any difference in the overall processing. However, in case of amino-N content, it showed the higher level of its contents at the process of Korean solar salt comparing to other. In case of microbiological, the total viable cells was detected most from the Australian solar salt during the initial stage of fermentation, but after 12-week of fermentation, the Chinese solar salt showed the largest number of total viable cells. Also, it found the Korean solar salt contained the lowest level of coliforms, while it found the highest level of coliforms contents in Chinese solar salt. However, there were no significant differences of microbiological characteristics from the salt-fermented shrimp made with 6 kinds of salt(p<0.05). As a result of sensory quality on salt-fermented shrimps, domestic salts was higher than imported. But there were no significant difference of sensory quality from the salt-fermented shrimps made with 6 different kinds of salt(p<0.05).