• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.55-63
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• 1977

As the important pathogens of potato storage diseases, Fusarium solani, F. reseum, F. oxysporum, and Erwinia carotovora were isolated from rot potato tubers. The cut potato pieces of the three cultivars, Epicure, Irish Cobbler, and Superior were held in moist chambers of $4^{\circ},\;14^{\circ},\;24^{\circ},\;and\; 34^{\circ}C$ and 7 days and then rated for suberin and periderm development. The cut potato pieces thus treated were inoculated with the four organisms and held at $24^{\circ}C$ for 9 days and then rated for decay. As the temperature and period of holding increased, more suberin and periderm were developed with decrease in decay. Although there were differences in pathogenicity of the organisms, varietal reaction and protective barrier development, the effect of temperature and holding period had greater importance for decay prevention. At $4^{\circ}C$ within 7 days of holding period the potato pieces developed no protective barrier with severe decay. It is required to avoid placing cut potatoes directly in cold storage of the low temperature. At $34^{\circ}C$ the pieces developed abundant protective barriers even though decay occurred in somecases. Practically no decay was found with moderate protective barrier development after 3 days and 5 days at $24^{\circ}C\;and\;14^{\circ}C$, respectively. Since the potato pieces decayed occasionally during the holding period when they were held at the higher temperature, the holding at $14^{\circ}C$ for longer than 5 days is considered to be feasible for prevention of storage rots.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.225-231
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• 2005

This study was carried out to observe the stability of riboflavin in dietary supplements. Dietary supplements were in the type of tablet, powder, capsule and liquid. Various factors on the stability of riboflavin such as effect of light, storage temperature and time were examined using HPLC method. Samples were exposed to various temperatures (-9, 4, $30^{\circ}C$) and light at room temperature far 9 months. As well as storage period became longer, reduction rate constant of riboflavin increased. Riboflavin reduction rate constants were higher during storage with light than without light. And there was a significant difference of reduction rate constants in types of dietary supplement. In other words, riboflavin in tablet types was significantly more stable than the others, and liquid type was the most unstable. Therefore, type, light, and packing container of dietary supplements containing riboflavin would be considered in order to establish their appropriate shelf lives. In consideration with riboflavin decrease in dietary supplements, riboflavin would be appropriate for the nutritional labelling guide when predicting them at the end of shelf lives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.83-88
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• 2009

After storing green tea powder for three months at three different temperatures (-20, 4, and $20^{\circ}C$) with three different relative humidities (RHs) (23, 69, and 81%), the chemical quality was evaluated with green tea, which was prepared by soaking 1.5 g of the powder into 100 mL of distilled water at $70^{\circ}C$ for 5 min. Total phenolic contents, total flavanol contents, and ascorbic acid contents of green tea powder stored at $4^{\circ}C$ with 23% RH changed from 267.5, 49.4, and 24.2 mg/g to 287.1, 44.9, and 36.9 mg/g, respectively, compared to the powder before storage. EGC and EGCG, the main catechins of green tea, also changed from 16.9 and 27.3 mg/g to 24.3 and 36.5, g/g, respectively, after storage for 3 months at $4^{\circ}C$ with 23% RH. However, when the green tea powder was stored at -20 or $20^{\cric}C$ with higher RH such as 69 and 81%, the chemical compounds were significantly decreased. The results indicate that temperature and RH are important during storage of green tea powder, and low RH and refrigerated condition ($-4^{\cric}C$) are preferable to increase or preserve the chemical compounds of the tea.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.356-363
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• 2009

This study was carried out to investigate the effect of hot boning and curing condition on the quality characteristics of ground chicken breast. Treatments were cured by four conditions follows; control (general curing method), T1 (after hot-boning and then immediately cured), T2 (after hot-boning and immediately cured, then frozen), and T3 (after hot-boning, immediately frozen, refrigerated and then cured). The pH of chicken breast in the state of pre-rigor was 6.22. The pH of cold storage or freezing chicken breast meat respectively were 5.70 or 5.61. The pH of T1 and T2 treatments were significantly higher than those of control and T3 treatment (p<0.05). After stored for 1 wk, the pH value of T1 treatment had a higher value than those of other treatments. T1 treatment had the highest water holding capacity and the lowest cooking loss among all treatments, regardless of the cooking methods. The reduction in diameter for T1 and T2 treatments was lower than those of control and T3 treatment (p<0.05). T1 treatment had the lowest fat loss and moisture loss among all treatments, and the emulsifying capacity of T1 treatment was the highest. The protein solubility of T1 treatment was significantly lower than that of T3 treatment.

• Journal of Food Hygiene and Safety
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• v.5 no.4
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• pp.219-228
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• 1990

Whey proteins in milk were analyzed by polyacrylamide gel electrophoresis and compared with respect to electrophoregrams, densitograms and concentrations of whey proteins in raw and market milk classified according to 3 kinds of pasteurization by low temperature long time. high temperature short time and ultra-high temperature short time. Relative composition of major whey protein constituents such as bovine serum albumin, ${\alpha}\;-\;lactalbumin\;and\;{\beta}-lactoglobulin$ in raw milk were 3.71:11.44:84.85 and not affected by low temperature long time and high temperature short time pasteurization, even though there were the tendencies of some declining in the actual concentrations. But by ultra-high temperature short time pasteurization compositions of whey protein were changed to 0: 64.75: 35 in which reflected the disapprearance of bovine serum albumin and the extensive decrease of ${\beta}-lactoglobulin$. Storage of low temperature pasteurized milk at $5^{\circ}C$ resulted in a slight decrease of ${\alpha}\;-\;lactalbumin\;a\;{\beta}-lactoglobulin$, but storage at $25^{\circ}C$ did not make any changes until3rd days of storage. Most of whey proteins in high temperature short time pasteurized milk were not affected during storage at $5^{\circ}C\;and\;25^{\circ}C$, but bovine serum albumin and ${\alpha}\;-lactalbumin$ diminished in 2-3 days of storage. Whey proteins of milk treated with ultra-high temeperature were not affected during storage at $5^{\circ}C\;and\;25^{\circ}C$ except a slight decrease of ${\alpha}\;-lactalbumin$ in 2nd day of storage at $5^{\circ}C$.

• Food Science of Animal Resources
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• v.29 no.5
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• pp.612-618
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• 2009

The objective of this study was to determine the antioxidant and antimicrobial effects of garlic juice and onion juice in emulsified sausage during cold storage. The sausages were into five groups: control, 1% garlic juice (T1), 3% garlic juice (T2), 1% onion juice (T3), and 3% onion juice (T4). Each sausage type was tested in triplicate and assigned to one of four storage periods: 0, 7, 14 and 21 days. As storage time increased, the presence of garlic juice and onion juice resulted in decreased pH, residual nitrite value, and increased peroxide value, TBARS (thiobarbituric acid reactive substance) values, and total plate counts. The pH value, peroxide value, TBARS, residual nitrite and total plate counts were significantly decreased by the addition of garlic and onion juice relative to the control (p<0.05). Especially, T2 was significantly (p<0.05) more effective in delaying lipid oxidation compared to the other treatment groups. However, no significant difference (p<0.05) was found in total plate counts among all the formulations on day 0. Also, the use of garlic juice resulted in much better antioxidant and antimicrobial effects than the use of onion juice and the control. In conclusion, this study demonstrates that the addition of 3% garlic juice (T2) to emulsified sausages tended to improve antioxidative and antimicrobial effects during storage relative to the other treatment groups.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.117-126
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• 2012

This study was conducted to assess the levels of microbiological hazards of preprocessed Namuls, which were served at the school foodservice. 19 preprocessed ground or root vegetables were collected from 21 schools in May to June of 2011. Heavy contamination of aerobic plate counts (from 3.39 to 8.42 logCFU/g) and total coliform groups (from 3.16 to 7.84 logCFU/g), enterobacteriaceaes (from 2.53 to 7.55 logCFU/g) were detected in preprocessed Namuls. In addition, the detection rates of Escherichia coli, Staphylococcus aureus and Bacillus cereus (emetic form) were 4.3%, 11.7% and 2.1%, respectively. In addition, sanitary indicative bacterium at preprocessing steps of root vegetables (lotus root, burdock root, bellflower root) and blanched Namuls (bracken, sweet potato vine, chinamul) were analyzed. Aerobic plate counts, coliform groups, and enterobacteriaceaes were not effectively removed during preprocessing including washing and soaking steps. In the case of blanched Namuls (bracken, sweet potato vine, chinamul), contamination levels increased more after drying process and no significant reduction effect on the levels of microbial contamination was observed during preprocessing steps. Thus, effect of preprocessing steps on the microbiological hazards in Namuls must be reevaluated to improve the microbiological quality of preprocessed Namuls at the school foodservice and retail markets.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.113-122
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• 2002

Beef loins that retailed in market were used as experimental samples. Some beef samples in raw state were packaged with PVDC as aerobic and vacuum condition. The other beef samples were cooked until core temperature arrived at 70$^{\circ}C$ and then packaged immediately in the same way of raw samples. After these samples were irradiated by electron beam 6kGy, irradiated samples were stored in refrigerator(2～4$^{\circ}C$). Identify and quantity of cholesterol oxides were analysed stored at 0 and 7 days, respectively. During the early stage of storage, 7$\beta$-hydroxycholesterol and 7-ketocholesterol were respectively produced from the raw meat samples, and the production of these chemicals were significantly higher (P$<$0.05) from the meats with aerobic packaging than those with vacuum packaging. With the passage of storage time, 7$\alpha$-hydroxycholesterol, 20$\alpha$-hydroxycholesterol, $\beta$-epoxide, $\beta$-epoxide and some other chemicals, which were not produced during the early stage of storage, were produced, Also, the production of these chemicals were significantly increased (P$<$0.05) with the passage of storage time. Cooked meat after irradiation and irradiated meat after cooking produced cholesterol on the 7th day of storage, although this chemical was not produced during the early stage of storage. Production of cholesterol oxides was significantly increased (P$<$0.05) with the passage of storage time for all treatments, and showed significantly lower value (P$<$0.05) with the vacuum packaging than aerobic packaging. Summarizing the aforementioned results, it was found that the production of cholesterol oxides was more easily affected by packaging condition than irradiation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1423-1430
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• 2014

This study investigated the effects of superheated steam (SHS) and high hydrostatic pressure (HHP) on the quality of Galbijjim. SHS cooking increased moisture and crude fat contents and decreased crude protein contents (P<0.05). The value of L was significantly higher upon SHS cooking compared to conventional cooking (CC), whereas a and b values were not significantly different among the samples. Hardness decreased more upon CC than SHS. The results of the safety storage experiment at refrigeration temperature showed that the total number of bacteria was lower in SHS-HHP than in CC-HHP. The thiobarbituric acid value increased to 0.70~1.56 mg malonaldehyde (MA)/kg in CC-HHP after 15 days, and SHS-HHP showed 0.69 (0 day)~1.24 (15 days, $10^{\circ}C$) mg MA/kg. Volatile basic nitrogen value was 18.07~36.76 mg% in CC-HHP, and that in SHS-HHP also increased to 17.06 (0 day)~35.76 mg% (15 days, $10^{\circ}C$). Overall, SHS cooking and HHP reduced microorganisms, which could improve product quality and sanitation.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.349-357
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• 2001

The effects of dietary conjugated linoleic aicd on pork quality was investigated using sixty four pigs. CLA was synthesized by alkaline isomerization method with corn oil. Pigs were devided into 4 treatment groups(16 pigs/group) arid subjected to one of four treatment diets(0, 0.1, 0.2, and 0.3% CLA diets) for 2 weeks before slaughter. Pork loin and belly were collected from the animals(105∼110kg body weight) slaughtering at the commercial slaughter house. Pork loin and belly meat were aerobic packaged and then stored during 2. 5. 8. 11 and 13 days at 4$\^{C}$ refrigerator. Samples were analysed for meat color, texture and sensory characteristics. There were no diference in meat color(L*, a*, b*), texture and sensory property among control and CLA treatment (s), and no changes as the storage period passed. This results mean that feeding CLA to pork doesn't change the meat color and texture of the pork what consumers consider when they buy some meat. Especially, feeding CLA to pork didn't transform sensory property of the pork. We considered these result as no problem in the pig fed with CLA.