In nuclear fuel development research, consideration of the back-end cycle is essential. In particular, a review of an in-reactor performance of nuclear fuel related to the various degradation phenomena that can occur during spent fuel dry storage is an important area. The important factors affecting the degradation of zirconium-based cladding during dry storage are the cladding’s hydrogen concentration and rod internal pressure after irradiation. In this study, a preliminary analysis of the in-reactor behavior of the HANA cladding, which has been developed and is currently undergoing licensing review, was performed, and based on this result, a comparative analysis between nuclear fuel with HANA cladding and current commercial fuel under storage conditions was performed. The results show that the rod internal pressure of nuclear fuel with HANA cladding is not significantly different from that of commercial cladding, and the hydrogen concentration in the cladding tends to reduce due to the increased corrosion resistance, so fuel integrity in a dry storage conditions is not expected to be a major problem. Although the lack of cladding creep data under dry storage conditions, the results from the Halden research reactor test comparing in-reactor creep behavior with Zircaloy-4 showed that there is sufficient margin for degradation due to creep during storage.

This study was carried out to investigate the changes of the microbiological contamination levels, pH, acidity, solid contents, total phenol contents, and color difference of cold-brew coffee products during 4 weeks at room and cold temperatures. The 17 sample coffees were purchased from regional cafes in Jeonju. Each coffee was self-blended by the cafes. Esherichia coli was not detected in all the samples, but bacteria were detected in 1 sample and yeast and molds were detected in 4 samples. Of the samples stored at room temperature (25oC) after 4 weeks, general bacteria were detected in 4 samples (3.0×101 cfu/ml-1.7×103 cfu/ml), and yeast and molds were detected in 11 samples (1.3×101 cfu/ml - 3.1×105 cfu/ml). In the case of the samples stored at cold temperature (4oC), general bacteria were detected in 3 samples, and yeast and molds were detected in 6 samples although the level of contamination was lower than that at room temperature. pH and acidity decreased during the storage period, but the total phenol content did not change. In the case of chromaticity, redness and yellowness tended to decrease.

The objective of this study was to compare the effect of semen extenders on the sperm motility, viability, acrosome integrity and functional integrity of plasma membrane (HOST: hypo-osmotic swelling test) during liquid preservation of Korean Native boar semen. In this experiment, semen was diluted in Androhep plus, Beltsville Thawing Solution (BTS), ModenaTM, Seminark and Vitasem LD. Sperm-rich fractions were collected from three Korean Native boars and sub-samples were diluted (30×106 spermatozoa/ml) in different semen extenders. Semen samples were stored at 17℃ for 96 hours. On everyday (0, 24, 48, 72, 96 h) after storage, the sperm characteristics relevant for fertility, such as sperm motility, viability, acrosome integrity and HOST positive were evaluated. The motility of spermatozoa stored in different extenders was no significantly different among other extenders (P>0.05). Also, no difference was observed among samples processed with different extenders in the percentage of sperm viability, acrosome integrity and HOST positive. All extenders maintained a high percentage (70%) of sperm motility, viability and acrosome integrity through 96 h of storage. The result of this study show that there was no significant differences among extenders in their capacity to preserve motility, viability and membrane integrity of spermatozoa from normal, fertile Korean Native boars for 96 h of liquid preservation at 17℃.

The objective of this study was to determine the effect of semen extenders on the motility, viability and fertility in vitro of spermatozoa during storage of fresh boar semen diluted in different commercial extenders used for pig artificial insemination (AI). In this experiment, semen were diluted in Androhep plus, Beltsville Thawing Solution (BTS), Modena, Seminark and Vitasem LD. Five ejaculates were collected from three Duroc boars and sub-samples were diluted (30×106 spermatozoa/ml) in different extenders. Semen was stored at 17℃ for 10 days. Sperm motility and viability was assessed using Computer-Assisted Semen Analysis (CASA) and flow-cytometry on 1, 3, 5 and 10 day post collection. The motility of spermatozoa stored in different extenders was gradually decreased by increasing the duration of storage of semen. However, there was not significantly different in the sperm motility and viability among other extenders. On the other hand, the in vitro-matured oocytes were fertilized and cultured in vitro to assess the fertility of boar spermatozoa stored for 3 and 10 days in different extenders. The percentage of morula and blastocyst were taken as indicators of fertility in vitro of spermatozoa. Therefore, there were no differences in the rate of embryos developed to the molular and blastocyst stage. There were no differences in the motility and fertility in vitro among 5 kinds of commercial boar semen extenders.

There were few data for the distribution of the indicator organisms in the commercial plant foods, and for the normal flora and for the foodborne agents within the country. First of all it must be investigated the distribution of the indicator organisms. And also it is very important to prepare the sanitation criteria for the plant foods through the microbiological e×amination and the investigation of tendency to change of the indicator organisms according to the storage temperature and period. The average number of total viable counts for grains was 2.9 × 10^5/g, psychrophilic bacteria 2.9 × 10^6/g, heterotrophic bacteria 3.1 × 10³/g, heat-resistant bacteria 2.1 × 10³/g Pseudomonas aeruginosa 23/g. That for beans was 6.3 × 10²/g, psychrophile 34/g, heterotroph 1.7 × 10²/g. That for sesames was 1.4 × 10^5/g, coliform 350/g, psychrophile 7.4 × 10⁴/g, heterotroph 5.8 × 10⁴/g, Pseud. aeruginosa 2.3 × 10³/g. heat-resistant bacteria 150/g. That for potatoes was 2.0 × 10^7/g, coliform 5.0 × 10⁴/g, psychrophile 1.8 × 10^7/g, heterotroph 1.4 × 10^7/g, heatresistant bacteria 3.3 × 10¹/g, Staphylococcus 2.7 × 10^5/g, fecal streptococcus 4.5 × 10³/g, Pseud. aeruginosa 7.0 × 10³/g. That for mushrooms was 1.2 × 10^8/g, psychrophile 9.4 × 10^7/g, heterotroph 1.0 × 10^9/g, heat-resistant bacteria 1.6 × 10^5/g, Pseud. aeruginosa 1.3 × 10³/g. That for vegetables was 5.9 × 10^(11)/g, coliform 1.8 × 10^6/g, psychrophile 1.1 × 10²/g, heterotroph 8.4 × 10^(11)/g, heatresistant bacteria 7.6 × 10^6/g, Staphylococcus 1.1 × 10^7/g, fecal streptococcus l.1 × 10⁴/g, Pseud. aeruginosa 5.2 × 10⁴/g. That for nuts 3.9 × 10⁴/g, coliform 3.9 × 10³/g, psychrophile 4.0 × 10^8/g, heterotroph 3.2 × 10^8/g, heat-resistant bacteria 400/g. In commercial grains and beans, SPC, psychrophile, heterotroph and heat-resistant bacteria stored at 10℃, 20℃, 30℃ were constant. Staphylococcus, coliform, Pseud. aeruginosa were decreased a little in grains, but were not detected in beans. In mushrooms, all indicator organisms were increased as time goes on and were increased rapidly at 20. In sesames, coliform was not detected at all temperature. psychrophile was increased for 7 days, the otners were constant. In potatoes, SPC, psychrophile, heat-resistant bacteria, heterotroph had a tendency to increase and the others were constant. In vegetables, indicator organisms were had a tendency to increase, psychrophile, heterotroph were rapidly increased after 7 days. In nuts, SPC, coliform, psychrophile, heterotroph, heat-resistant bacteria, Pseud. aeruginosa were constant, staphylococcus and fecal streptococcus were not detected.

The average number of total viable counts for the commercial pork tested was 19/g, coliform 1.8/g, psychrophilic bacteria 15/g, heterotrophic bacteria 12/g, fecal streptococcus 6.2/100 g, Pseudomonas aeruginosa 13/100 g and none of heat-resistant bacteria and Staphylococcus was detected. That for the commercial beef tested was 130/g, coliform 5.2/g, psychrophile 140/g, heterotroph 28/g, Staphylococcus 1.2/g, fecal streptococcus 9.5/100 g, Pseud. aeruginosa 1.9/100 g and heat-resistant bacteria was not detected. That for the commercial chicken tested was 8800/g, coliform 53/g, psychrophile 4600/g, heterotroph 4700/g, fecal streptococcus 9.9/100 g, Pseud. aeruginosa 2.5/100 g. That for milk was 4700/ml, psychrophile 120/ml, heterotroph 420/ml and the others were not detected. That for the commercial cheese was 3.2/g, psychrophile 2.3/g, heterotroph 1.6/g, Staphylococcus 1/g, fecal streptococcus 9.1/g. That for fermented milk was 10^7/ml, heatresistant bacteria 10^6/ml, fecal streptococcus 2400/100 ml, lactobacillus 3.2 × 10^(15)/ml, in accordance with lactic acid bacteria and the others were not detected. There was not detected any indicator organisms from ham, sausage, butter, eggs and quails in the commercial fooods tested. SPC, coliform, psychrophile and heterotroph in commercial meats stored at 10℃ were increased rapidly as time goes on but heat-resistant bacteria, staphylococcus, fecal streptococcus and Pseud. aeruginosa were constant. At 20℃, SPC, coliform, psychrophile, heterotroph and fecal streptococcus were the highest at 7 days and heat-resistant bacteria, staphylococcus and Pseud. aeruginosa were increased a little. At 30℃, all indicators were increased rapidly for 3 and 7 days and then decreased rapidly. All indicator organisms were increased at the level of 10/g for 14 days in meat products stored at 10℃, but SPC, psychrophile and heterotroph in meat products stored at 20℃ were increased at the level of 10^5/g. It showed that the indicators in meat products stored at 30℃ had a tendency to increase at the level of l0₂/g relative to those stored at 20℃. SPC, psychrophile and heterotroph in milk stored at 10 increased up to the level of 10₄/ml, but coliform, staphylococcus, fecal streptococcus and Pseud. aeruginosa were not detected. As stored at 20℃ and 30℃, they were increased rapidly for 1 or 3 days and then constant for a long time.

Chicken carcass microflora were evaluated for aerobic microorganisms after defeathering, evisceration, washing, chilling, and sanitizing during a commercial chicken processing and storage at wholesale and retailsale levels. Sampling was at between December 1997, and March, 1998. Tap water washing and sanitizing with 25 ppm chlorine for 10 sec significantly (P$lt;0.05) reduced aerobic plate counts (APC) and gram-negative bacterial counts (GNC) on chicken carcasses from a commercial chicken-processing plant. After 4 days at 2±2℃, APC and GNC on chicken carcasses in retailsale store rapidly increased compared to those in wholesale store (P$lt;0.05). Chicken wings from retailsale store significantly (P$lt;0.05) decreased generation time (GT) compared to other chicken carcasses.

In order to investigate bacterial sanitary condition of fish and shellfish, we examined the normal flora in the 25 species of commercial fish and shellfish, and also proportional change of normal flora by storage period and temperature. Isolated 334 were isolated in the normal fish and shellfish and predominant genera were Pseudomonas (25.2%), Staphylococcus (10%), Acinetobacter (7.2%), Vibrio (6.9%), Micrococcus (5.4%), Aeromonas (5.2%), and Enterobacter (5.2%). In accordance with storage period and temperature, Pseudomonas grew on high ratio at 10℃ steadily, but Proteus had increased proportionally at 20℃ and 30℃. Additionally, Citrobacter, Moganella, and Pasteuralla had increasd, while Achromobacter, Acinetobacter, Yeast, and Micrococcus had decreased by period.

This paper intends to investigate commercial fish and shellfish 25 species (fish 8 species, shellfish 7 species, crustacean 3 species, molusc 4 species and echinodermata) for the distribution of sanitary indicator organisms (total viable counts, coliforms, staphylococci, vibrios, and enterococci) and diatributional change of indicator organisms according to storage temperature and period. The logarithmic mean of total viable counts for total commercial fish and shellfish 25 species was 5.41±0.26 CFU/g, and in accordance with fish and shellfishes, crustacean 6.76±0.67 CFU/g, shellfish 5.67±0.56 CFU/g, echinodermata 5.47±0.50 CFU/g, fish 5.021±0.38 CFU/g, and mollusc 5.03±0.65 CFU/g. The logarithmic mean of enterococci was 2.36±0.37 CFU/g, and in accordance with fish and shellfish, crustacean 3.44±0.12 CFU/g, shellfish 3.87±0.45 CFU/g, echinodermata 3.38±0.0 CFU/g, fish 2.16±0.41 CFU/g and mollusc 0.01±0.0 CFUIg. The logarithmic mean of vibrios was 1.60±0.59 CFUIg, and in accordance with fish and shellfish, crustacean 4.23±0.11 CFU/g, shellfish 3.58±0.90 CFUIg, echinodermata 1.64±0.34 CFU/g, fish 1.79±0.67 CFU/g and mollusc 1.07±0.61 CFU/g. The logarithmic mean of staphylococci was 1.60±0.59 CFU/g, and in accordance with fish and shellfish, shellfish 0.01±0.00 CFU/g, echinodermata 3.51±0.60 CFU/g, fish 1.68±0.64 CFU/g, crustacean 0.34±0.33 and mollusc 2.90±0.11 CFU/g. The logarithmic mean of coliforma was 2.2±0.32 CFU/g, and in accordance with fish and shellfish, echinodermata 3.58±0.89 CFU/g was highest, shellfish 3.25±0.30 CFU/g, crustacean 3.23±0.49 CFU/g, fish 2.18±0.63 CFU/g, peeled shellfish 1.80±0.51 CFU/ g and mollusc 1.55±0.95 CFU/g. As the results of research of the change of the contaminated indicator microflora in working with storage period at 10℃, 20℃ and 30℃, total viable counts was increased without storage temperature and enterococci were decreased slowly at 10℃, but increased at 20 and 30℃ Vibrios were decreased slowly at 10℃, decreased at 20℃ and 30℃ in 2 days after increased rapidly. Staphylococci were increased promptly without storage temperature in 2 days, then the total viable counts were maintained. Coliforms were increased at 10℃ by 7 days, then decreased or maintained after 14 days, changed at 20℃ in accordance with fish species in 2 days, then returned to the initial total viable count, and decreased rapidly at 30℃ on 2 days. By the way, there were no difference among the species.

This study was investigated the effects of various commercial sanitizers on microbial characteristics in fresh-cut iceberg lettuce during storage. For screening sanitizer, lettuce was cut and dipped in chlorine water (0.2 ml·L-1), solution of organic acids such as ascorbic acid, citric acid, acetic acid, mixture of ascorbic acid and acetic acid (1-6%), and solutions of commercial sanitizers such as Formula 4TM (1,3,4%), Fresh produce washTM (1,3,4%), CleancolTM (1%), ChitocholTM (1%) and Natural CaTM (0.1%) for 3 min, respectively. Washing lettuce with selected sanitizers resulted in reduction of aerobic bacteria of more than 2 log CFU/g. Initial pH of lettuce was related with the pH of sanitizers. pH ranged from 4.7 to 6.1 in Formula 4 (4%, pH 1.7) and Natural Ca (0.1%, pH 12.0), respectively. Chlorine water showed consistent and significant inhibition effect in all of microorganisms except total coliform. Over 3% of Formula 4 and Fresh produce wash were found to have high bactericidal activity among sanitizers. The sanitizers of chlorine water, Fresh produce wash, Chitochol and Natural Ca were effective in reducing yeast and mould populations. As coliform and E. coli, Formula 4 (4%) showed the highest bactericidal activity. The bactericidal effect of commercial sanitizers during storage varied with the kinds and concentrations of tested sanitizers. Although inhibition effect was not showed during storage, these results suggest that commercial sanitizers could be an alternative to chlorine for washing fresh-cut produce.

In an attempt to test experimental condition of preparing grape powder, grapes having less commercial value was used and tried. With drying method, spray and freeze drying were satisfactory to produce power. Moisture content and odor retention were better by the latter method. Three grape strains stored for 40 days contained more odors than those stored for 5 days. Maltose 90% plus dextrin 10% was suitable for drying support. To increase odror sense, citric acid and vitamin C can be added up to 0.1 and 0.2%, respectively. Considering these conditions, grape complex powder prapared from grape powder 20% comprising drying support, glucose 79.7%, citric acid 0.1%, vitamin C 0.2% with freeze drying was the best by overall evaluation including sensory test. When campbell and neomuscut were mixed by 15:5 or 10:10, sensory evaluation was also ameliorated.