• Korean Journal of Poultry Science
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• v.28 no.3
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• pp.215-224
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• 2001

Since nitrogen(N) is a volatile compound affected by many environmental factors, determining the N content of manure tends to be difficult. Upon arrival in the laboratory, the manure should be moist and refrigerated. Manure samples will have variable N contents due to drying temperature, and the presence of soil in the sample will affect N content. Acidification of the sample prevents ammonia volatilization and should be done before drying. It is recommended that manure samples be pretreated with a strong oxidizing agent, KMnO$_4$, followed by digestion under reduced conditions (reduced Fe-$H_{2}$ $SO_{4}$ ), which achieves a complete recovery of both $NO_{3}$ -N and $NO_{2}$ -N without a low recovery of $NH_{4}$ -N, resulting in a more accurate determination of N content. Accuracy of results for N content determined by recently developed rapid analysis techniques in the field should be tested by comparison with results obtained at laboratories using approved standard methods. Most commonly, the Kjeldahl system is used to determine manure N content. More research is needed on the effects of species, breed, age and individuals on the nutrient contents of manure. The procedures for manure sampling on the farm, shipping and handling of the sample until it reaches the laboratory, and the methods of sampling of the manure at the laboratory must be studied. Development of animal agricultural laboratories where feed, manure, soil, and water are all analyzed by appropriate specialists is needed.

• Korean Journal of Poultry Science
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• v.37 no.4
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• pp.313-321
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• 2010

This study was conducted to investigate the effects of dietary supplementation of mulberry leaves and dandelion extracts on pH, meat color, TBARS (thiobarbituric acid reactive substance), and VBN (volatile basic nitrogen). Two hundred broiler chickens were fed diets for five weeks containing 1% mulberry leaves extracts (T1), 2% mulberry leaves extracts (T2), 1% dandelion extracts (T3), and 2% dandelion extracts (T4). At the end of five weeks feeding experiment, broilers were slaughtered, and stored at $4^{\circ}C$ for five weeks. As storage time increased, the presence of mulberry leaves and dandelion extracts resulted in decreased pH, and $L^*$ and increased TBARS, VBN, and $a^*$ value in all treatment groups (P<0.05). The pH value, TBARS, and VBN were significantly decreased by the supplementation of mulberry leaves and dandelion extracts relative to the control (P<0.05). Therefore, mulberry leaves and dandelion extracts had the possibility to improve shelf life of chicken meat. Especially, T4 was significantly more effective in delay lipid oxidation compared to the control group. However, no significantly difference was found in pH, TBARS, and VBN among mulberry leaves and dandelion extracts treatment groups. In conclusion, this study demonstrates that compared to control group, supplementation of mulberry leaves and dandelion extracts were effective in decreasing pH, TBARS, and VBN and increasing $a^*$ value.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.379-385
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• 1995

The effect of low concentrations of ethanol (3-7％, v/v) in tryptic soy broth (TSB) as an antibacterial agent against Listeria monocytogenes was tested at -20, 5, 35, 45, 50 and 55$^{\circ}C$. Increasing concentrations of ethanol progressively inhibited initial growth of L. monocytogenes at 35$^{\circ}C$. Growth occured at 5％ ethanol, but only after a prolonged lag period. The number of viable cells of L. monocytogenes declined during incubation at 7％ ethanol. TSB containing 3-7％ ethanol was inoculated with 10$\^$5/-10$\^$6/ cells/$m\ell$ or L. monocytogenes and incubated at low temperatures (5$^{\circ}C$, -20$^{\circ}C$). In the presence of 3％ of ethanol at 5 or -20$^{\circ}C$, bacterial growth was inhibited more than 90％ of control cells. TSB containing 3-7％ ethanol was inoculated with 10$\^$6/-10$\^$7/ cells/$m\ell$ of L. monocytogenes and incubated at high temperatures (45$^{\circ}C$, 50$^{\circ}C$, 55$^{\circ}C$). Decrease in viability of the cells incubated at 45 or 50$^{\circ}C$ was slow and the survival of L. monocytogenes was not affected so much in the presence of 3％ of ethanol. The viability of L. monocytogenes was decreased with increasing concentration of ethanol and temperature. Decimal reduction times (D-values) based on tryptic soy agar plates at 55$^{\circ}C$ were 20.1, 12.6, 7.4 and 4.2 min in 0, 3, 5 and 7％ ethanol, respectively.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.159-164
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• 2014

This study was conducted to investigate whether water chilling had effect on water retention, freshness or internal temperature of chicken carcasses during chilling or storage in two different chicken processing plants (designated as A and B). A total of 240 carcasses from chicken processing plants (n = 120 per chicken processing plant) was randomly sampled and evaluated the effect of water chilling on carcass characteristics (i.e., water retention, water loss or freshness during chilling or storage). Torrymeter value was used as an indicator of freshness in chicken carcasses. Water chilling did not affect carcass water retention between the processing plants. However, chicken carcasses processing in B plant exhibited significantly higher freshness (p<0.05) compared with those in A plant. This difference in freshness was mainly due to the longer transit time through the water chiller in A versus B plants. Water loss of carcasses during storage was not different between plants. It was found that carcass freshness can be affected by water chilling time as manifested in this study. Further study is warranted to see whether freshness or microbiological status of chicken carcasses may be affected depending on the chilling methods, i.e., air or water chilling.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.212-218
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• 1999

The effects of gamma irradiation (1, 3 and 5 kGy) and packaging methods (air and vacuum) on the growth of microorganisms contaminated in beef was investigated during storage at different temperatures (-20, 4 and $25^{\circ}C$). The initial microbial population of beef was $8.0{\sim}10^2\;CFU/g$ in total aerobic bacteria, $2.0{\times}10^2\;CFU/g$ in total lactic acid bacteria, $8.0{\times}10^1\;CFU/g$ in molds, $6.0{\times}10^2\;CFU/g$ in Pseudomonas sp. and $7.0{\times}10^2\;CFU/g$ in coliforms, respectively. Gamma irradiation at 5 kGy completely eliminated pathogenic bacteria in beef. Gamma irradiation at such dose and subsequent storage at less than $4^{\circ}C$ could ensure hygienic quality prolong the microbiological shelf-life resulting from the reduction of spoilage microorganisms. The different packaging methods of beef caused negligible changes in the growth of microorganisms during storage.

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.101-109
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• 1996

This study was done to find out the methods of long-term use of liquid boar semen in 100 ml plastic bottle for artificial insemination and to investigate differences between Lactose-Egg yolk and Biitschwiler diluents according to storage temperature, and effect of final glycerol concent ration in Lactose-Egg yolk diluent. Liquid boar semen diluted with Lactose-Egg yolk diluent showed significantly higher sperm motility (p<0.05) after 0.5 and 2h incubation at 37$^{\circ}C$,than Butschwiler diluent at all storage length when it was preserved in the 5$^{\circ}C$ refrigerator. The NAR acrosome in Lactose-Egg yolk diluent a after 0.5 and 2h incubation at 37$^{\circ}C$, respectively, during preservation periods was similar to that in Biitschwiler diluent. When liquid boar semen was preserved at 15$^{\circ}C$, liquid boar semen in the Butschwiler diluent showed significantly higher percentages of sperm motility and NAR acrosome from third day to seventh than that in Lactose-Egg yolk diluent. In the effect of final glycerol concentration of liquid boar semen in the Lactose-Egg yolk diluent, the final glycerol concentration of 2% showed higer percentages of sperm motility and NAR acrosome than that of 0, 1, 3, and 5%. Farrowing rate, litter size and average pig weight at birth did not differ significantly between Lactose-Egg yolk and But schwiler diluents. As a result of this study, we found out that liquid boar semen can be stored for 6-7 days at 5$^{\circ}C$ in Lactose-Egg yolk diluent and at 15$^{\circ}C$ in Butschwiler diluent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.2
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• pp.80-84
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• 1988

The change of cell counts of Vibrio vulnificus in meat homogenates of fish and shellfish by the storage time and temperature was examined to get basic information for precautionary steps against septicemia from slices of raw fish (sashimi). Therefore, we inoculated raw and cooked meat homogenates of fish and shellfish with Vibrio vulificus M-8 (isolated from shellfish ) and stored them at $-20^{\circ}C,\;4^{\circ}C\;and\;30^{\circ}C$ for 72 hours. Vibrio vulnificus M-8 was not detected in 32 hours when it was frozen and stored at $-20^{\circ}C$ after inoculating them into phosphate buffer solution at concentration of $10^5\;cell/ml$, while the existance of Vibrio vulnificus was identified after 72 hours of storage at the same temperature in case of inoculation into the meat homogenate of yellow tail. The cell count of Vibrio vulnificus was decreased as about $20\%$ of initial count after 2 hours storage at $4^{\circ}C$ in phosphate buffer solution with fish and shellfish homgenates. From the experimental results it was recognized that Vibrio vulnificus was labile to the cold stress. In comparison to the growth of growth of Vibrio M-8 at $30^{\circ}C$ in the raw and cooked meat of the yellow tail(Seriola guingueradita), snapper(Chrysophrys major), ark shell(Anadra brouhgtonii), and oyster(Crassostrea gigas), the raw meat homogenates were more excellent than the cooked ones though all fish and shellfish meat homogenates were proves to be good for the growth of the microbe.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.442-448
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• 2013

Lactic acid bacteria (LAB) are a representative group of probiotics and used in many fermented foods and beverages. Several recent studies have shown that LAB are present in makgeolli which is a traditional Korean alcoholic beverage. However, most LAB are intolerant of more than 6% (v/v) alcohol concentrations. For this reason, alcohol-tolerant LAB are isolated from kimchi, makgeolli and nuruk using alcohol containing selective media. After being cultured in MRS broth containing 13% (v/v) alcohol, the two strains which showed the highest increasing O.D values, were finally selected. As results of 16S rRNA gene sequencing and biochemical characterization using an API kit, the two species were identified as Pediococcus acidilactici K3 and S1. In addition, the identified two strains produced bacteriocins against Staphylococcus aureus. When compared with the P. acidilactici type strain, the two selected strains possessed two to three time higher growth on 12-13% (v/v) alcohol containing MRS broth. The viability of P. acidilactici K3 and S1 when inoculated in makgeolli and stored at $10^{\circ}C$ did not decrease through a period of one month indicating that the selected strains can be used for LAB containing makgeolli.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.252-257
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• 1994

The sprouting characteristics of Scirpus planiculmis and storage methods of corm for the herbicide screening were investigated under both laboratory and greenhouse conditions. Sprouting and elongation of S. planiculmis corms were continued during storage at low temperature ($5^{\circ}C$) and wet condition. However, sprouting of corm was failed when the surface water was removed from the corm, and elongation was reduced by the treatment of 0.5-1.0% sodium chloride(NaCl) solution. Alternate temperature was more effective on the sprouting of S. planiculmis corm than constant temperature. Optimum temperature for the sprouting of S. planiculmis corm was alternation between $25^{\circ}C$ to $35^{\circ}C$. Storage at $-20^{\circ}C$ for 10 min. or 14.7% dehydration made the corm of S. planiculmis to fail for sprouting. S. planiculmis corm was more tolerant to sodium chloride than Echinochloa crus-galli or Oryza sativa(Donginbyeo) seeds. Sprouting rate was decreased by cutting of the corm. Sprouting percent by vertical cuttings, horizontal cuttings, and vertical plus horizontal cuttings were 72, 56, and 28%, respectively.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.173-180
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• 2010

This study was conducted to investigate the effects of dietary supplementation of mulberry leaves and dandelion extracts on performance, proximate composition, heating loss, drip loss, and blood characteristics of chickens. One hundred sixty broiler chicks were fed diets for five weeks containing 1% mulberry leaves extracts (T1), 2% mulberry leaves extracts (T2), 1% dandelion extracts (T3), and 2% dandelion extracts (T4). At the end of five week feeding experiment, broiler were slaughtered, and stored at $4^{\circ}C$. T2 resulted in much better weight gain and feed conversion than other treatment groups. As storage time increased, all treatment groups resulted in increased heating loss and drip loss (P<0.05) but no significant difference were observed among the treatment groups. In blood composition, GOT (glutamic oxaloacetate transaminase), GPT (glutamic pyrubic transaminase), total cholesterol, and triglyceride were significantly decreased by the supplementation of mulberry leaves and dandelion extracts compared to the control (P<0.05). Especially, T4 was significantly (P<0.05) more effective in improving blood composition compared to other treatment groups. However, no significant difference (P>0.05) were found in LDL-cholesterol among all treatment groups. In conclusion, these data indicate that compared to other treatments, supplementation of 2% dandelion extracts (T4) were most effective in decreasing total cholesterol and triglyceride and increasing HDL-cholesterol.