• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.89-92
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• 2003

The effect of gamma-irradiation on microbiological growth in kale juice during storage was studied. Fresh kale juice was prepared and irradiated at 0, 1, 3, 5, 7, 10, and 15 kGy. D values for total bacteria, yeast and mold, Salmonella, E. coli, and Pseudomonas were 3.6, 4.0, 3.2, 1.4, and 1.6 kGy, respectively. E. coli and Pseudomonas were eliminated completely at 5 and 7 kGy, respectively. Gamma-irradiation also reduced total viable bacteria during storage. Therefore, these results indicate gamma-irradiation can prevent microbial spoilage of fresh kale juice by inactivating pathogenic microorganisms.

• Food Science of Animal Resources
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• v.44 no.1
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• pp.19-38
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• 2024

Meat contains high-value protein compounds that might degrade as a result of oxidation and microbial contamination. Additionally, various pathogenic and spoilage microorganisms can grow in meat. Moreover, contamination with pathogenic microorganisms above the infectious dose has caused foodborne illness outbreaks. To decrease the microbial population, traditional meat preservation methods such as thermal treatment and chemical disinfectants are used, but it may have limitations for the maintenance of meat quality or the consumers acceptance. Thus, non-thermal technologies (e.g., high-pressure processing, pulsed electric field, non-thermal plasma, pulsed light, supercritical carbon dioxide technology, ozone, irradiation, ultraviolet light, and ultrasound) have emerged to improve the shelf life and meat safety. Non-thermal technologies are becoming increasingly important because of their advantages in maintaining low temperature, meat nutrition, and short processing time. Especially, pulsed light and pulsed electric field treatment induce few sensory and physiological changes in high fat and protein meat products, making them suitable for the application. Many research results showed that these non-thermal technologies may keep meat fresh and maintain heat-sensitive elements in meat products.

• Journal of Radiation Industry
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• v.4 no.1
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• pp.59-64
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• 2010

This study was conducted to evaluate the microbial (Total aerobic count, Coliform, Coagulase positive Staphylococci, Salmonella, Yeast/Mold, Escherichia coli, Bacillus cereus), Hunter'color values ($L^*$, $a^*$, $b^*$) and organoleptic quality of freeze-dried Miyeokguk, Korean seaweed soup in space food. Bacillus cereus was 1 log level while not detected in the sample irradiated at 10 kGy. Hunter's color values of the samples irradiated less than 10 kGy was not significantly different (p>0.05). The sensory evaluation result showed that the preference scores in all the sensory properties decreased when it was irradiated over 10 kGy, but sensory score of less than 10 kGy samples was similar in all terms. Therefore, it was considered that gamma irradiation at 10 kGy was enough to sterilize the freeze-dried Miyeokguk without deterioration of sensory quality.

• Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.276-286
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• 2022

This study is focused on the effect of phycobiliprotein extraction of Gracilaria on the quality of common carp burgers, and the application of nanoliposomes containing pigment in the improvement of its antimicrobial and antioxidant activity of burgers during refrigerated storage in 18 days. Burgers were incorporated with phycobiliprotein and liposomal phycobiliprotein (2.5% and 5% w/w), and their chemical and microbial changes in terms of pH, peroxide value (PV), thiobarbituric acid (TBA), total volatile basic nitrogen (TVB-N), total viable counts (TVC), psychrotrophic bacterial counts (PTC), and sensory characteristics were evaluated. Results presented a nanoliposome size of about 515.5 nm with capable encapsulation efficiency (83.98%). Our results showed non-encapsulated phycobiliprotein could delay the deterioration of common carp burgers, as a reduction in PV, TBA, and TVB-N, TVC, and PTC values in burgers treated with free and nano encapsulated phycobiliprotein. Moreover, the potential of phycobiliprotein was improved when it was encapsulated into chitosan coated liposomes. Burgers treated with 5% nanoliposomes displayed the lowest amount of lipid oxidation and microbial deterioration in comparison to others during storage. According to chemical, microbial and sensory evaluation, the shelf life of common carp burgers was increased in samples treated with encapsulated phycobiliprotein at 2.5% and 5%, as compared to the control (p ≤ 0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1649-1655
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• 2013

This study is conducted to investigate the quality characteristics of kimchi with added Allium hookeri root (AHR) during a 56-day fermentation process at $4^{\circ}C$. AHR was added to salted cabbage at concentrations of 0, 5, 10, and 20% (w/w). The quality characteristics of the kimchi with added AHR were determined by measuring pH, acidity, salinity, reducing sugar, microbial amounts, and sensory evaluation. AHR had a higher level of crude lipid and potassium than other kinds within the Allium family. All kimchi with added AHR gradually decreased in the pH level compared to Baechu kimchi until 2 weeks, and kept a higher level of pH than Baechu kimchi until 8 weeks. Salinity showed a range of 1.87~2.43% over 8 weeks. The reducing sugar content showed no difference between all kimchi. In sensory evaluations, overall acceptance, taste and texture were highest in kimchi with added 10% AHR.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.377-381
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• 2007

The aim of this study was to evaluate the microbial safety and quality changes of Korean sliced pork jerky, and to investigate these properties over 90 days and 28 days of storage at room temperature $(25^{\circ}C)$ and elevated temperature $(35^{\circ}C)$. Based on the microbial counts of pork jerky, mesophilic bacteria were detected at 2.50 log CFU/g at day 0. The mesophilic bacterial count did not change significantly for all samples, and coliform bacteria and Bacillus cereus were not detected in any samples during storage at either $25^{\circ}C\;or\;35^{\circ}C$. The following physicochemical qualities were also investigated: TBA value, Aw, and pH. In the case of $25^{\circ}C$ storage, the Aw of Korean sliced pork jerky was 0.72 at day 0, and was reduced to 0.58 after 90 days of storage. The TBA value increased as the storage time increased, and was 0.52 after 90 days of storage. The pH of all samples did not change significantly. In the case of $35^{\circ}C$ storage, the TBA, Aw, and pH values were not significantly different from those obtained during $25^{\circ}C$ storage. In addition, the sensory properties of all samples were not significantly different between storage at the two temperatures. In conclusion, these results suggest Korean sliced pork jerky could be used to study the development of commercial pork jerky.

• 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.

• Food Science and Preservation
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• v.15 no.4
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• pp.606-611
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• 2008

Myungran Jeotkal, Korean fermented seafood, and its ingredients(hot red pepper powder, ginger, garlic, and seasoning mix) were irradiated with 0, 0.5, 1.0, 2.0, and 5.0 kGy of gamma rays and stored at 4C for 4 weeks to determine changes in microbiological and sensory characteristics. Water activities of Myungran Jeotkal, hot red pepper powder, ginger, garlic, and seasoning mix were 0.89 0.56, 0.98, 0.99, and 0.07, respectively. Myungran Jeotkal was observed to be initially contaminated. Total aerobic bacteria, yeast and mold, and coliform levels were 6.7, 4.3, and 3.6 log CFU/g, respectively. Irradiation at 2 kGy afforded approximately a 4 log reduction in total aerobic bacteria, and a 3 log drop in both yeast and mold levels and coliform bacteria(P<0.05). No viable microbial cells were detected in Myungran Jeotkal after 5 kGy of irradiation(at a detection limit of 101 CFU/g). The total aerobic bacterial level in red pepper powder was 6.3 log CFU/g and this component, of the tested ingredients, contributed most to the microbial contamination of Myungran Jeotkal. The initial count of total aerobic bacteria, 6.3 log CFU/g, was significantly reduced to 4.5 log CFU/g after irradiation(P<0.05). Sensory evaluation showed that gamma irradiation of up to 5.0 kGy did not adversely affect overall acceptability of Myungran Jeotkal or its ingredients during cold storage. Therefore, gamma irradiationwas effective to extend the shelf-life of Myungran Jeotkal.

• Food Science and Preservation
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• v.20 no.4
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• pp.518-523
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• 2013

This study was performed in order to evaluate the quality properties of Kimchi containing 0%, 10%, 20%, and 30% of oriental melon peel parts. The Kimchi was fermented for 28 days at a temperature of $15^{\circ}C$. The pH, titratable acidity, total microbial counts, and lactic acid counts were measured, and the sensory characteristics including taste, color, chewiness, and overall acceptability were evaluated. During the 28 days of fermentation, the pH dramatically decreased between the 7th and 21st day of the fermentation period, and maintained thereafter in control (0%). However, the pH in peel-added groups slightly increased up to the 14th day and decreased up to the 21st day with 4.13~4.41. The total microbial counts in control were significantly higher than those in the peel-added groups. This trend was maintained throughout the fermentation period. A similar trend was found in the lactic acid microbial counts throughout the fermentation period. During the sensory analysis, the values of taste were significantly higher in the 20% and 30% peel-added Kimchi, while the chewiness and overall acceptability were significantly higher in the 20% peel-added Kimchi than those in control. This study showed an improvement in the storage period of Kimchi products with 20% of oriental melon peel, as well as the possibility of a commercial Kimchi manufacture.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.593-605
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• 2018

The present study was undertaken to assess the efficacy of sapota powder (SP) as natural preservatives and its better utilization in food processing with the incorporation of various levels of SP (2, 4, and 6%) by replacing lean meat. Based on the sensory attributes, pork patties with 4% incorporation of SP was found optimum and selected for further storage studies with control under aerobic and modified atmosphere packaging at refrigeration temperature ($4{\pm}1^{\circ}C$) for 42 days for assessing its antioxidant and antimicrobial efficiency. During entire storage period, indicators of lipid oxidative parameters such as thiobarbituric acid reactive substances (TBARS), free fatty acids (FFA) and peroxide value (PV) followed an increasing trend for control as well as treated products; however, treated product showed a significantly (p<0.05) lower value than control. A significantly lower (p<0.05) microbial count in treated patties than control was noted during entire storage. The sensory attributes are better retained in treated product as compared to control and even on $42^{nd}$ day, overall acceptability of treated patties was found to fall in moderately acceptable category (5.95 in aerobic packets and 5.91 in modified atmosphere packets). Therefore SP has potential to enhance antioxidant and antimicrobial properties of pork patties during storage.