• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.157-162
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• 2008

Enterobacter sakazakii was initially referred to as yellow-pigmented Enterobacter cloacae and reclassified in 1980. E. sakazakii infection cause life-threatening meningitis, septicemia, and necrotizing enterocolitis in infants. Powdered infant formula (PIF) and baby foods may be the important vehicle of E. sakazakii infection. It has been reported that E. sakazakii was isolated from PIF and sunsik ingredients produced in Korea. Some infants have been fed sunsik as a weaning diet. Therefore, it is necessary that this organism should be inactivated on preparing PIF and sunsik at homes and in hospitals. The cocktail of three Korean E. sakazakii strains (human, sunsik and soil isolates) were used to investigate the inactivation of this organism with hot water at 50, 60, 65, 70 and $80^{\circ}C$ and microwave heating for 60, 75, 90, 105 and 120 sec. Reconstituted PIF and sunsikwere inoculated with cocktailed vegetative cells of E. sakazakii at 6 log CFU/mL. Thermal inactivation of vegetative cells of E. sakazakii were achieved by reconstituted PIF and sunsik with hot water at $60^{\circ}C$ or greater and with microwave heating at 2,450 MHz for 75 sec or longer. Considering that biofilm formation of E. sakazakii was adapted to survive the dry environment that is PIF and sunsik and thermal resistance increased, it is suggested that inactivation of E. sakazakii was used by hot water at $70^{\circ}C$ or greater and microwave heating for 90 sec or longer. Reconstituted PIF and sunsik were inoculated with cocktailed vegetative cells of E. sakazakii at 2 to 3 log CFU/mL to investigate the growth curve of this organism and stored at 5, 10, 15, 20, 25, 30 and $35^{\circ}C$. Viable counts slightly changed at 5, $10^{\circ}C$ during 48 h but grew at $15^{\circ}C$ or greater. Considering that E. sakazakii is able to grow in infant formula milk at refrigerator temperature, reconstituted PIF and sunsik that are not immediately consumed should be discarded or stored at refrigeration temperatures within 24 h.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.225-234
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• 2009

The aim of this study was to analyze moisture, crude protein, crude lipid, vitamin C and sugar changes in selected Korean chestnut cultivars such as Danteack, Deabo, Seokchu, Okkwang and Byunggo during storage at $4^{\circ}C$ and $-10^{\circ}C$ for 10 months. The moisture contents of selected Korean chestnut cultivars ranged from 49.9 to 57.4%. The moisture content of Seokchu was the highest. The contents of moisture in white kernel were higher than that in yellow kernel. The content of moisture showed decreasing tendency after 10 months of storage. The crude protein and crude lipid contents in whole kernel of selected Korean chestnut cultivars were $3.3{\sim}4.2%$ and $0.3{\sim}1.6%$, respectively. The crude protein content of Deabo was the highest. The crude protein in Danteack, Seokchu, Okkwang and Byunggo was increased during storage at $4^{\circ}C$ for 10 months, while that in whole kernel of Deabo was decreased and no changes in crude protein in yellow kernels of Deabo were observed. The crude protein in Okkwang was increased during storage at $-10^{\circ}C$ for 10 months. The cold storage was found to have higher composition change of crude protein than the freezing storage. The content of crude lipid in Daebo and Byunggo was decreased during storage at $4^{\circ}C$ and $-10^{\circ}C$. Yellow kernels of Deabo, Okkwang and Byunggo were found to have higher crude lipid content than white kernels. The vitamin C content also decreased during storage at $4^{\circ}C$ and $-10^{\circ}C$ and the decrease in vitamin C content was higher at $4^{\circ}C$ than $-10^{\circ}C$. Vitamin C was not detected after 3 months storage at $-10^{\circ}C$. The sugar content increased at the latter period storage at $4^{\circ}C$ and $-10^{\circ}C$. The sugar content of selected Korean chestnut cultivars ranged from $36.2{\sim}44.3%$ and Dantaek had the highest sugar content.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.314-319
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• 2007

The aims of this work were to compare the effects of dehairing methods and sex on pork quality and cold storage stability. For this study, one half of40 pigs were dehaired by scalding in the same abattoir, and the other half by dehiding. Each treatment consisted of one half gilts and one half castrated male pigs. Meat quality traits were measured at 24 hr after slaughter, and thiobarbituric acid (TBA), metmyoglobin contents and total plate counts (TPC) were evaluated at 1, 7, 14 and 21 days of cold storage. The carcass weight and backfat thickness of pigs dehaired by scalding were significantly higher than those dehided (p<0.05). Compared to scalded carcasses, dehided carcasses had a lower longissimus dorsi muscle temperature (p<0.05). Furthermore, dehided carcasses had significantly lower drip loss than scalded carcasses (p<0.05). However, meat color parameters were not affected by the dehairing method. During cold storage, TBA values of scalded carcasses were slightly higher initially, whereas the dehided carcasses had higher TBA values at 21 days (p<0.05). The total plate counts (TPC) associated with scalding and dehiding treatment were not significantly different at any point during cold storage. The TPC exponentially increased in both scalded and dehided carcasses from 7 to 14 days of cold storage.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.59-67
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• 2006

This study was conducted to investigate the changes in some physicochemical properties, including pH, moisture and ash content, Ca, Na, Mg, K, crude saponin and codonoposide, of cultivated Codonopsis lanceolata, which were packed with woven polypropylene(WP) or low density polyethylene(LDPE, thickness 0.04 mm) bag and stored at $4^{\circ}C\;or\;20^{\circ}C$ for 30 days. pH of the juice of fresh Codonopsis lanceolata was 5.3 and decreased significantly during storage. Storage temperature exerted more influence upon the content of moisture and ash than package materials. The concentration of Ca, Mg, Na and K were 427.3mg, 203.4mg, 10.2mg, and 619mg per 100g dry matter respectively. The contents of Ca and Na were not changed significantly, but the contents of Mg and K were decreased during room temperature storage. It was revealed that the juices of stored sample had darkened and redness and yellowness were somewhat deeper than those of fresh sample. 1g of the cultivated Codonopsis lanceolata had 29.3mg of crude saponin and 3.78mg of codonoposide, and the changes of them during storage at various conditions were not significant.

• FLOWER RESEARCH JOURNAL
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• v.17 no.2
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• pp.106-113
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• 2009

Germination percentage of Korean native lily seeds was high at $20-25^{\circ}C$. It was almost 100% in L. cernuum, L. callosum, L. amabile, and L. concolor, 88.0% in L. lancifolium, and 73.0% in L. maximowitzii, respectively. Meanwhile, it was low rate of 34.0%-54.0% in L. distichum, L. hansonii, and L. tsingtauense. Germination was mostly delayed of $15^{\circ}C$ and days to germination were more shortened in species with higher germination percentage. Even though the effect of daylength was not considerable in germination rate, it was promoted in L. maximowitzii but it was delyed in L. hansonii under long day. The effect of soaking in hot PGRs solution in L. callosum, L. cernuum, L. amabile, L. lancifolium, and L. concolor did not show any difference in comparison with non-treatment. However, it was improved by BA in L. maximowitzii. Longer period of cold wet storage resulted in improved germination percentage in L. maximowitzii and L. lancifolium, while it affected decreased percentage in L. distichum and L. hansonii. Days to germination were shortened by longer period of cold wet storage regardless of species. Germination percentage in dry storage was higher under cold temperature than room temperature and under desiccator storage than outside desiccator, it was highest under desiccator storage at $4^{\circ}C$. It was drastically reduced by the non-use desiccator storage at room temperature L. concolor, however it was improved only by the use of desiccator L. maximowitzii for a long time.

• Food Science and Preservation
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• v.12 no.6
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• pp.522-528
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• 2005

Effects of packaging and storage temperature on the quality and shelf life of mungbean sprouts(vigna radiata (L.) Wilczek) were studied Mungbean sprouts were packaged in polypropylene films(PP) and oriented polypropylene films(OPP) with 200 g, 250 g, and 300 g and stored at $4^{\circ}C,\;8^{\circ}C$ and $12^{\circ}C$, respectively. The deterioration of quality of mungbean sprouts during storage was caused by wilting of hypocotyl, abscission of cotyledon and softening of tissue. Total weight loss never exceeded $1\%$ and no visible signs of shrivelling of mungbean sprouts were observed. At $4^{\circ}C,\;30{\mu}m$ of OPP film per 250 g mungbean sprouts provided the optimal atmosphere composition(i.e. $3\%\;\O_2\;and\;5\%\;CO_2$). A shelf life of 6 days was achieved with these conditions. Hardness of hypocotyl, when deterioration in freshness began, was about 1,027.2 g when considerably deteriorated Hunter b value was 13 in deteriorated hypocotyl, vs. 11 for hypocotyl of fresh mungbean sprouts was accelerated by fluctuating storage temperature by the increment of storage time. It also was found that the optimum shelf life period was estimated to be 6, 2 and 2 days for 4, 8 and $12^{\circ}C$, respectively.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.342-348
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• 2016

The objective of this study was to compare the change of S. Enteritidis with S. Typhimurium populations in liquid egg products. S. Enteritidis or S. Typhimurium was inoculated into egg white and egg yolk and stored at 8, 10, 15, 25, and $35^{\circ}C$, respectively. In egg white, no growth of S. Enteritidis and S. Typhimurium was observed at 8, 10, 15, and $35^{\circ}C$, while both S. Enteritidis and S. Typhimurium in egg white stored grew more than 1 log CFU/ml after 50 hours storage at $25^{\circ}C$. In egg yolk, there was no growth of S. Enteritidis and S. Typhimurium at $8^{\circ}C$ but growth of both strains was observed at 10, 15, 25, and $35^{\circ}C$. Since growth of S. Enteritidis and S. Typhimurium was only observed in egg yolk, primary growth models for both strains were developed using modified Gompertz equation and then secondary models for lag time (LT), specific growth rate (SGR), and maximum population density (MPD) were developed as a function of temperature. At all temperatures, more rapid growth of S. Enteritidis than S. Typhimurium was observed in egg yolk, indicating the greater risk of S. Enteritidis than S. Typhimurium in egg products. In conclusion, the results indicate that temperature control less than $8^{\circ}C$ is very important to ensure safety of liquid egg products, especially liquid egg yolk.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.312-319
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• 1996

Oyster (Crassostrea virginica) and Weakfish (Cynoscion regalis) were stored at 6, 0, -4 and -20$^{\circ}C$ for up to 45 days and examined for changes in microflora. Aerobic plate counts (incubated at 21$^{\circ}C$) were performed at selected times during storage and 495 isolates (255 isolates from oyster and 240 isolates from Weakfish) were randomly selected from the plates during the storage. Before the storage of the fishes, viable counts of oyster were 4.9${\times}$10$\^$5/ CFU/g of meat and those of Weakfish were 1.5${\times}$10$^4$ CFU/cm$^2$of skin. Microflora of oyster before storage, the major isolates identified as Pseudomonas spp. (67%) and Vibrio spp. (20%). Pseudomonas ll1/1V-H and Flavobacterium/Cytophaga were predominant genus in the microflora of oyster during cold storage at 6, 0, -4 and -20$^{\circ}C$. The composition of the microflora of Weakfish before storage, Acinetobacter (40%) and Moraxella (33%) were the major species, with Pseudomonas and Vibrio constituting a small percentage of the total isolates. The microflora shifted to predominantly Pseudomonas spp. during storage at 6. 0 and -4$^{\circ}C$, making up from 60 to 100％ of isolated strains. During frozen storage, the percentage of isolates identified as Mnraxella increased to 40-60% of the total isolates. During cold storage, halophilic bacteria (Pseudomonas lII/IV-H and Vibrio) were predominant in oyster while nonhalophilic bacteria (Pseudomonas III/IV-NH and Moraxella) were predominant in Weakfish. Vibrio spp. were higher in oyster than in Weak fish. Listeria spp. were not isolated but unidentified ${\beta}$-hemolytic bacteria were islolated from both of the fishes during cold storage.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.40-46
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• 1997

This study was conducted in order to determine the effect of preparing conditions(refrigerating and freezing of dough, dough size, frying temperature, kneading degree and ingredient amount) on the dehydration, absorbed oil content and sensory characteristics of Yackwa. There were no significant differences on the dehydration, absorbed oil content and sensory characteristics between the control Yackwa and those prepared by refrigerating and freezing of dough. In the dough size (large, medium, small), dehydration and absorbed oil content was increased as the size became smaller. It was shown that overall acceptability was high in medium size Yackwa. There were no significant differences on the dehydration of Yackwa under various frying temperature and kneading degree. On the other hand, absorbed oil content of Yackwa was decreased as the frying temperature became higher and kneading degree increased. Dehydration of Yackwa was increased as the amount of sesame oil, honey and sozu increased. There were no significant differences on the absorbed oil content of Yackwa as the amount of sesame oil increased. The absorbed oil content was increased as the amount of honey increased, whereas the absorbed oil content decreased as the amount of sozu increased. Shininess, softness, brittleness and oily taste was increased as the absorbed oil content increased in sensory evaluation of Yackwa prepared by different frying temperature, kneading degree and ingredients amount. It was shown that above preparing conditions affected the absorbed oil content and sensory characteristics of Yackwa.