• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.842-850
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• 2020

The objective of this study was to evaluate the effect of the depuration process (artificial seawater sterilization using UV light) for extending the shelf life of raw oyster Crassostrea gigas and maintaining food quality. To confirm the effects of depuration, microbiological (viable cell count) and several physiochemical analyses (pH and glycogen levels in shucked oyster and pH, soluble protein, and turbidity in filling water) were carried out during the storage of raw oysters. The results showed that depuration could effectively extend the shelf life (2-3 days) of raw oysters with minimal change in food quality, including pH and glycogen content. Thus, the depuration process proposed in this study could successfully be applied to processing practices for other shellfish to extend their shelf life and contribute to the management of seafood safety issues.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.324-331
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• 2009

Peeled whole onions (PWO) were cleaned at various hypochlorous acid (HA) concentration and steeping time and packed in LDPE bag keeping at $10^{\circ}C$ for 12 days and $35^{\circ}C$ for 3 days, in order eventually to examine microbiology, surface color and sensory quality. At the early stage of storage, it was found that total bacterial counts at H-II keeping at $10^{\circ}C$ after 1 minute steeping were $2.60\;{\pm}\;0.18\;log\;CFU/g$, and those after 3 minutes steeping were $2.10\;{\pm}\;0.18\;log\;CFU/g$ which showed less than the control. The total bacterial counts at H-III were detected after 4 days. The total bacterial counts of PWO treated HA increased as steeping time became longer, HA concentration increased, and storage temperature went down. E. coli was not detected at all treatments. It was also found that during the treatment the L-value showed decreasing trend, but the parameter a- and b- value showed increasing trend. But these trends were mitigated as HA concentration increased. The result of sensory quality evaluation for the appearance showed that the sample stored with $10^{\circ}C$ gained higher evaluation than that with $10^{\circ}C$, while the control and H-III gained highest points significantly (p < 0.05) for the sample keeping at $10^{\circ}C$ after 12 days storage. The sensory odor of onion showed similar to that for the appearance, and the 8-day treatments of H-II and H-III showed no significantly difference (p < 0.05). On the basis of the results above, it is likely to be more effective to prolong the period of circulation of PWO if you use HA over 50 ppm for washing PWO and storage at $10^{\circ}C$. This study will contribute to improve safety and quality in circulation of PWO.

• Food Science and Preservation
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• v.24 no.6
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• pp.734-745
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• 2017

The effects of combination treatment with sulfur dioxide generating pad ($SO_2$ pad) and modified atmosphere packaging (MAP) on grape quality were examined under simulated exporting condition and actual export to Los Angeles, USA. The 'Campbell Early' grape harvested in Hwaseong, Gyeonggi was precooled at $0^{\circ}C$, selected and packaged at $10^{\circ}C$, and stored at $0^{\circ}C$ for 30 days. The treatment was as follows: general export packaging (control), only $SO_2$ pad, combination of $SO_2$ pad and MAP (perforated polyethylene film, $SO_2$ pad+MA). In case of control and only $SO_2$ pad under simulated exporting condition, the grape quality changes with storage time were decrease in hardness and brush length, increase in stem browning, and increased in shattering rate. The treatment of $SO_2$ pad+MA was the most effective in preserving the grape quality since $SO_2$ concentration inside the package remained around 2.9 ppm by MA film. Grape exports from harvest to local distribution of the USA took 30 days, and only $SO_2$ pad+MA package showed no fungus, maintained brush length and rachis color, and was lowest at 4.0% of shattering rate since the concentration of $SO_2$ in the package was about 4.0 ppm. As a result, it was considered that the combination of $SO_2$ pad and MA was the most effective way to maintain freshness of grape during long-term marine transportation and extend the shelf-life in exporting countries.

• 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.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.103-108
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• 2020

Recently, consumer demand for safe but minimally processed food has rapidly increased. For this reason, many food processing industries are applying hurdle technology to enhance food safety, extend shelf life, and make foods appear minimally processed. Meanwhile, studies have shown that a treatment (stress) meant to inactivate foodborne pathogens may trigger adaptation mechanisms and could even offer cross protection against subsequent treatments. Also, certain routine farm practices such as antibiotic and herbicide use could result in the development of antibiotic-resistant pathogens. Such bacteria may be tolerant to food processing-associated stress and be more likely to remain viable in processed foods. In this review, we discuss the correlation between food processing-associated stress and antibiotic resistance. We also discuss molecular mechanisms such as the use of sigma factors, SOS response pathways and efflux pumps as means of cross protection against antimicrobial compounds and other food processing-associated stresses.

• Journal of Mushroom
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• v.20 no.3
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• pp.138-146
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• 2022

To optimize initial cooling conditions, forced-air cooling was applied to freshly harvested oak mushrooms at 2 levels (0℃ for 30 minutes, at 0℃ for 1 hour) followed by room cooling at 3 levels (-3℃ for 1 day, 0℃ for 1 day, 3℃ for 1 day). After initial cooling, the oak mushrooms were packaged with PVC film, then held in a storage room at 1℃ for 6 weeks. Quality characteristics and percentage marketability were then investigated. As a control, Mushrooms were placed in storage with no initial cooling. The quality factors impacting marketability of fresh oak mushrooms were color change and appearance of decay. Off-odor did not occur or developed only slightly, so it did not affect oak mushroom quality within 6 weeks of low temperature storage. In all treatment groups, the shelf life in which 100% marketability was maintained was up to 3 weeks. At week 5, percent marketability of the 3 treatment groups 1 hour room cooling treatment at 0℃, 1 hour forced air cooling, and control was 100%. 80% In the group that underwent 30 min forced air cooling retained 80% marketability, and the group exposed to 1 day in room cooling at -3℃ retained 86.7% marketability. At week 6 of 1℃ storage, the marketability ratio was 80% in the 1 day room cooling at 0℃ group, 66.7% in the 1 day room cooling at 3℃ group, 46.7% in the 1 hour forced air cooling group, and 33% or less in all other treatment groups. Therefore, the most suitable initial cooling parameter to extend shelf-life of oak mushrooms is 1 day of in room cooling at 0℃ immediately after harvest.

• Food Science and Preservation
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• v.20 no.3
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• pp.386-393
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• 2013

This study was conducted to investigate the change in quality attributes of fresh-cut potatoes with heat and browning inhibitor treatment (CW: dip in the cold water for 30 sec at $4^{\circ}C$, HW: dip in the water for 60 sec at $55^{\circ}C$, AA: dip in the 0.1% solution of ascorbic acid for 60 sec at $4^{\circ}C$, HA: dip in the 0.1% solution of ascorbic acid for 60 sec at $55^{\circ}C$) during storage at $5^{\circ}C$. During storage, fresh-cut potatoes treated with HA showed the lowest value in surface color. PPO and PAL activities of fresh-cut potatoes treated with HA were gradually increased during storage. Hardness, weight loss, soluble solids content and moisture content had no significant difference between the treatments. In sensory acceptance, fresh-cut potatoes treated for HA marked the best quality. Conclusively, heat and browning inhibitor treatment showed the positive effect on browning inhibition while maintaining the quality of fresh-cut potatoes.

• Food Science and Preservation
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• v.17 no.6
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• pp.908-913
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• 2010

Modified atmosphere packaging (MAP) was evaluated for the storage of pumpkin rice cake as a means of preserving quality and extending shelf-life. Retail-sized amounts of rice cake were packaged in trays under different modified atmosphere conditions (air, vacuum, 60% $CO_2$/40% $N_2$ and 100% $CO_2$) using gas-barrier plastic film; control was in air-permeable stretch wrap. The packages were stored at $20^{\circ}C$ with periodical measurement of package atmosphere and cake quality attributes. The modified atmosphere packages of 60% $CO_2$/40% $N_2$ and 100% $CO_2$ inhibited the growth of molds/yeasts completely and significantly retarded the growth of aerobic bacteria. All the packages except that of 100% $CO_2$ showed the reduction of internal $O_2$ concentration and increase of the $CO_2$ with storage time due to the microbial activity. There has been slight decrease of $CO_2$ concentration for 60% $CO_2$/40% $N_2$ and 100% $CO_2$ packages just after start of the storage possibly due to dissolution of headspace $CO_2$ into the cake. Any MAP conditions did not affect the retrogradation of the rice cake. Surface color of the cake within affordable microbial quality limit was not affected significantly by packaging conditions.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.817-822
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• 1998

The authors found out that Aspergillus oryzae ATCC 22787 has the activity to produce a pretty strong chitosanase. Therefore, the strain was used for preparing the chitosan hydrolysate with high antimicrobial activity. The antimicrobial activity of the chitosan hydrolysate was increased gradually with decreasing of viscosity of the solution. The chitosan hydrolysate showing viscosity $5{\sim}10{\;}cp{\;}(30^{\circ}C)$ of 2% solution was revealed the most strong antimicrobial activity. The growth of the Bacillus sp. isolated from the fish meat paste was inhibited with the concentration of 50 ppm. The astringent taste of chitosan solution was reduced with decreasing of viscosity of the solution. The fish meat paste products containing 0.3% chitosan hydrolysate was extended its shelf life by 6 days stored at $15^{\circ}C$, 4 days at $20^{\circ}C$ and 2 days at $30^{\circ}C$.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.269-277
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• 2009

This paper reports the results of the research on the effects of probiotic yogurt on the microbiological quality, pH, and sensorial characteristics of fresh chicken meat when packed with probiotic yogurt. The chicken meat pieces were packed with yogurt and were stored at $10^{\circ}C$ for 7 days. Samples were taken after 0, 2, 4, and 7 days of storage, and were analyzed for total bacterial count, E. coli, and coliform, and for the chemical parameters, including the pH. In the control group (packed without yogurt), the Pseudomonas species predominated when the spoilage was obvious after 4-day storage at $10^{\circ}C$. The yogurt-mixed chicken meat package was found to have a significantly lower total viable count and significantly fewer coliform bacteria during storage. Furthermore, the yogurt package showed a growth-inhibiting effect on the Salmonella typhimurium, which were inoculated into the chicken meat pieces for the study. The study findings indicate that probiotic yogurt can be used in packing fresh chicken meat to decrease the population of spoilage bacteria therein and to extend its shelf life.