• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.161-165
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• 2000

Spectroradiometric light transmittance from 300 to 1,100nm in the greenhouse covered with the CEM BIO polyethylene film was greater than that in the greenhouse covered with polyethylene film (control). As a whole, solar radiation transmittance into greenhouse was a half level, due to shades caused by double layer covering, frame and equipment. Net radiation energy emitted throughout surface of the greenhouse covered with CEM BIO polyethylene film was 5,424.5W.m$^{-2}$ , which was lower by 2.9% as compared to that of the greenhouse covered with polyethylene film. Photosynthetically active radiation from 400 to 700nm of the greenhouse covered with CEM BIO polyethylene film was 3,861.2W.m$^{-2}$ , which was higher by 3.8% as compared to hat of the greenhouse covered with polyethylene film. Accumulated minimum air temperature from Oct. 7, 1997 to Oct. 16, 1997 of the greenhouse covered with CEM BIO polyethylene film was 100.5$^{\circ}C$, which was higher by 2.5$^{\circ}C$ as compared to that of the greenhouse covered with polyethylene film. As results, height, stem diameter, leaf count, leaf area, fresh weight and dry weight of green pepper plants and canopy production structure measured at 30 days after transplanting were enhanced. Mean fruit weight n the greenhouse covered with CEM BIO polyethylene film was 11.28 g and 1.25 g greater as compared to that in the greenhouse covered with polyethylene film, due to increased fruit diameter and flesh thickness. Percent marketable fruits produced in the greenhouse covered with CEM BIO polyethylene film were 96.1%, and was greater by 2.7% thant that of the greenhouse covered with polyethylnee film due to decreased infection, sterility, severe curve and twisted fruits. The green pepper yield of the greenhouse covered with CEM BIO polyethylene film from Nov. 19, 1997 to Feb. 3, 1998 was greater by 974 kg per hectare than that of the greenhouse covered with polyethylene film, but the total fruit had no difference.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.359-363
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• 2015

This study was conducted to investigate the differences in the physicochemical properties of organic and conventional milk from Chungnam and Jeonbuk, Korea. The milk was collected from 10 organic and 10 conventional milk farms in February, March and August, and then analyzed for milk composition, minerals and fatty acids. Organic milk showed lower fat (p<0.01) and total solid (p<0.05), but higher phosphorous (p<0.01) content than conventional milk. However, there was no difference in the content of lactose or the somatic cell count. Organic milk showed lower (p<0.01) stearic acid and total saturated fatty acid content, but higher (p<0.01) total, mono-, and poly-unsaturated fatty acid content. These results showed that organic and conventional milks differ mainly in their fat and unsaturated fatty acid content. Due to increasing consumer interest in food safety and health, organic milk, which contains more beneficial fatty acids, might be preferred over conventional milk.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.495-503
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• 2011

We evaluated the quality characteristics of fresh-cut produce (potato, sweet potato, carrot, radish, zucchini, cucumber, and green bell pepper) washed with sodium hypochlorite, which were vacuum packaged, and stored at 4 and 10$^{\circ}C$. The L-values of the fresh-cut potato and sweet potato decreased during storage. Lower PPO activities of potato and sweet potato were observed at 4$^{\circ}C$ than those at 10$^{\circ}C$ and development of potato and sweet potato browning was delayed at 4$^{\circ}C$. Total aerobic count and coliform increased continuously at 10$^{\circ}C$ during storage. Diced zucchini and shredded sweet potato had the greatest reduction in hardness among the fresh-cut produce during storage. Differences in the rate of quality change were observed according to the kinds and cut types of produce. Thus, a quality maintenance period for each type of fresh-cut produce must be determined, which will lead to the safe use of fresh cut produce in foodservice establishments.

• Journal of Food Hygiene and Safety
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• v.11 no.1
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• pp.57-70
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• 1996

This paper intends to investigate commercial fish and shellfish 25 species (fish 8 species, shellfish 7 species, crustacean 3 species, moluse 4 species and echinodermata) for the distribution of sanitary indicator organisms (total viable counts, coliforms, staphylococci, vibrios, and enterococci) and distributional change of indicator organisms accordion to storage temperature and period. The logarithmic mean of total viable counts for total commercial fish and shellfish 25 species was 5.41$\pm$.026 CFU/g, and in accordance with fish and shellfishes, crustacean 6.76$\pm$0.67 CFU/g, shellfish 5.67$\pm$0.56 CFU/g, echinodermata 5.47$\pm$1.50 CFU/g, fish 5.02$\pm$0.38 CFU/g, and mollusc 5.03$\pm$0.65 CFU/g. The logarithmic mean of enterococci was 2.36$\pm$0.37 CFU/g, and in accordane with fish and shellfish, crustacean 3.44$\pm$2.12 CFU/g, shellfish 3.87$\pm$0.45 CFU/g, echinodermata 3.38$\pm$0.0 CFU/g, fish 2.16$\pm$0.41 CFU/g and mollusc 0.01$\pm$0.0 CFU/g. The logarithmic mean of vibrios was 1.60$\pm$1.59 CFU/g, and in accordance with fish and shellfish, crustacean 4.23$\pm$1.11 CFU/g, shellfish 3.58$\pm$0.90 CFU/g, echinodermata 1.64$\pm$0.34 CFU/g, fish 1.79$\pm$0.67 CFU/g and mollusc 1.07$\pm$0.61 CFU/g. The logarithmic mean of staphylococci was 1.60$\pm$1.59 CFU/g, and in accordance with fish and shellfish, shellfish 0.01$\pm$0.00 CFU/g, echinodermata 3.51$\pm$0.60 CFU/g, fish 1.68$\pm$0.64 CFU/g, crustacean 0.34$\pm$0.33 and mollusc 3.90$\pm$0.11 CFU/g. The logarithmic mean of coliformas was 2.52$\pm$0.32 CFU/g, and in accordance with fish and shellfish, echinodermata 3.58$\pm$1.89 CFU/g was highest, shellfish 3.25$\pm$0.30 CFU/g, crustacean 3.23$\pm$0.49 CFU/g, fish 2.18$\pm$0.63 CFU/g, peeled shellfish 1.80$\pm$0.51 CFU/g and mollusc 1.55$\pm$0.95 CFU/g. As the results of research of the change of the contaminate indicator microflora in working with storage period at 1$0^{\circ}C$, 2$0^{\circ}C$ and 3$0^{\circ}C$, total viable counts was increased without storage temperature and enterococci were decreased slowly at 1$0^{\circ}C$, but increased at 20 and 3$0^{\circ}C$. Vibrios were decreased slowly at 1$0^{\circ}C$, decreased at 2$0^{\circ}C$ and 3$0^{\circ}C$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 1$0^{\circ}C$ by 7 days, then decreased or maintained after 14 days, changed at 2$0^{\circ}C$ in accordance with fish species in 2 days, then returned to the initial total viable count, and decreased rapidly at 3$0^{\circ}C$ on 2 days. By the way, there were no difference among the species.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.277-284
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• 2012

The objective of this study was to investigate and evaluate microbial contamination levels of leafy greens (perilla leaf and lettuce) and its distributing conditions at different seasons (Feb, May, Aug, and Nov of the year 2011) in order to provide insight into any potential health hazards associated with consumption of these commodities. Leafy greens were collected from a farm located in Geumsan, Chungnam and wholesale markets (WM) and traditional markets (TM) located in Suwon. At the same time, temperature and relative humidity fluctuations experienced by the leafy greens during distribution from the farm to the distribution center were measured by a data logger. The contamination levels of perilla leaf and lettuce were determined by analyzing total plate count. Coliform groups, Bacillus cereus, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes and Staphylococcus aureus were determined. The contamination levels of total aerobic bacteria, coliform groups and B. cereus in both vegetables sampled during May and August found to be higher than those sampled during February and November. E. coli O157:H7, Salmonella spp., L. monocytogenes were not detected in the vegetables analyzed in this study. There were no significant trends between samples at WM and TM in the contamination levels. Relative humidity of vegetables distributed from the farm to the distribution center showed over 90% during distribution regardless of measured seasons. In the case of background microflora on leafy greens, the density was significantly increased at 20, 30 and $37^{\circ}C$ during storage of 24h. E. coli O157:H7 and B. cereus inoculated on the leaves also showed similar increases in the storage tests. The microbial contamination levels determined in this study may be used as the fundamental data for microbial risk assessment.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.360-366
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• 2010

Doenjang (fermented soybean paste) is one of the korean traditional fermented soybean product which is consumed with cooked rice as a soup or paste. During the fermentation, soybean protein hydrolyzed into amino acids and various peptide, and various organic acids by mirobes related and enzymes produced by meju fermentation. Some commercial products locationally samples give more sour taste than normal due to abnormal fermentation which the reasons are not clear. Three samples that gave sour taste organoleptically were collected and analyzed their characteristics such as pH, moisture content, acidity and microbial counts. The pH of the sour sample were lower than the normal with higher acidity as pH 5.39 (normal) to pH 4.36 (S2) and 15.80 ml of(0.lN NaOH consumed) to 21.80 ml (S1) respectively. Salt and moisture contents were different with sour and normal Doenjang as 16.38% (normal) to 8.92% (S3) in salt and 55.94% (normal) to 49.34% (S1) in moisture content. Total viable counts were $4.1{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2), and $3.4{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2) in acid producing microbes at BCP plate. Yeast and mold were not detected. The composition of acids as mainly lactic acid and acetic acid of sour Doenjang. Total free amino acids content were lower the sour Doenjang than the normal.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.243-248
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• 1998

Ark shell was known as shellfish that had hemoglobin as blood pigment and the action of mecidine, was consumed the great part of it as raw material, though it was produced about 13,000 M/T per year. Ark shell was processed the infinitesimal quantity as conned product, bout canned ark shell had problem that occurrenced discoloration after heat treatment during processing and storage. This discoloration mechanism during processing and storage was not cleared. This study was carried out to understand characteristics of the hemoglobin as blood pigment and carotenoid as meat pigment in ark shell and management of proper processing conditions for prevention of oxidation and discoloration by thermal treatment. When treated by digestion of 0.1% BHA, 0.1% Tenox-II, 0.5% Na2EDTA, 0.05% NDGA and 3% salt soln., 0.1% BHA solution was most suitable for stability of carotenoid that the retention ratio of carotenoids were 63.1% after heating to 116$^{\circ}C$ for 120 minutes. In preparation of canned ark shell and storage at 37$\pm$1$^{\circ}C$ for 60 days, the chemical composition, pH and salinity ere stable. And contents of total carotenoid were decreased slightly from 0.83mg% to 0.727mg%. The viable cell count were 6.92$\times$103 cfu/ml at raw ark shell, after processed and storage were not detected. The predominant amino acids in the raw ark shell were glutamic acid(19.7%), arginine(16.0%), glycine(12.6%), alanine(12.2%) and aspartic acid(7.6%). When 60 days stored, the contents of amino acid were stable. And the predominant nuclotide and their related compounds in the raw ark shell were hypoxanthine(2.14$\mu$mol/g), IMP(1.94$\mu$mol/g) and ATP(0.87$\mu$mol/g), and storage at 37$\pm$1$^{\circ}C$ for 60 days, the quantity order were same as raw material.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.342-349
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• 2003

Escherichia coli O157：H7, Staphylococcus aureus and Salmonella enteritidis are food borne pathogens involved in food poisoning in numerous countries. This study aimed to obtain knowledges on the survival of Esc coli O157：H7, Sta aureus and Sal. enteritidis in the yoghurt added with water extract of Omija(Schizandra chinensis). The growth inhibition of Schizandra chinensis extract on the food borne pathogens were measured by total microbial count and effect of growth inhibition was correspondent to the concentration of Schizandra chinensis extract. The highest growth inhibition effect of Schizandra chinensis extract was shown on the Sta aureus followed by Sal. enteritidis and Esc. coli O157：H7. The number of surviving Esc. coli O157：H7 cell(3.55${\times}$10$\^$5/ CFU/mL) was decreased to 1.00${\times}$10$^1$∼3.00${\times}$10$^1$ CFU/mL after 24 hours incubation by the addition of 0.4∼l.0％ of Schizandra chinensis extract in the yoghurt. And also the viable cell counts of surviving Sta. aureus cells (initial inoculum 1.24${\times}$10$\^$5/ CFU/mL) were decreased gradually to 4.00${\times}$10$^2$∼8.50${\times}$10$^2$ CFU/mL after 48 hours of incubation, but the viable cells of Sal. enteritidis were not detected after 24 hours of incubation. Growth of the food borne pathogens was strongly inhibited by the addition and incubation of Schizandra chinensis extract for 48 hours in the yoghurt.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.555-561
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• 2008

Ninety-nine samples of powdered infant formula in a market were collected from the local market and their contaminations for total aerobic bacteria, coliform, FAO/WHO Category A, B, and C pathogens were analyzed. Total aerobic bacteria were detected in 92 of 99 samples (93%) at levels of $1.83{\pm}0.68\;Log\;MPN/g$. These levels were below legal levels specified for infant formulas except for one sample detected by 4.5 Log CFU/g. Coliform was detected in 12 of 99 samples (12%) at levels of $1.26{\pm}1.03\;Log\;MPN/g$ whereas non-detection was required according to the specification of coliform in infant formulas. Escherichia coli was detected in 1 of 99 samples by 0.48 Log MPN/g. Salmonella and Enterobacter sakazakii among Category A weren't detected in all the samples. Enterobacteriaceae, Category B group, were detected in 25 samples of total 99 samples (25%) by $0.83{\pm}1.37\;Log\;MPN/g$. Enterobacteriaceae identified by API 20E were Escherichia vulneris, Es. hermannii, Pantoea spp., Citrobacter koseri, Klebsiella pneumoniae, En. cloaceae. Bacillus cereus among Category C was highly detected in 29 of 99 samples (29%) at levels of $0.69{\pm}0.32\;Log\;MPN/g$ with the most probable number count method, which were below legal levels for the specification of B. cereus in infant formulas. Clostridium perfringens, E. coli O157, Staphyloccus aureus, Listeria monocytogenes, Yersinia enterocolitica, and Campylobacter jejuni/coli were not detected. Contamination level of major pathogens was low and falls within the range of specification of infant formulas. However, Enterobacteriaceae and B.cereus showed the high prevalence and some Enterobacteriaceae causing disease were detected. Therefore, it is necessary to monitor the potential pathogens continually and reduce them to improve the microbial quality of non-sterilized powdered infant formulas.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.659-667
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• 2000

Quality attributes of fresh-cut green onion(Allium fistulosum L.) as affected by rinsing and packaging were investigated in terms of flesh weight, color, viable cell counts, sensory properties during storage at $10^{\circ}C$. Fresh green onions were trimmed, cut, and rinsed with cold water(approximately $5^{\circ}C$) as well as chlorine solution(100 mg/L) and then packaged in low density polyethylene film pouches of $63\;{\mu}m$ thickness. Rinsing treatments with cold water or chlorine solution did not significantly influence changes in microbial populations but sensory characteristics, resulting in cut green onions of better visual quality as compared to the control without rinsing. Fresh-cut green onions were also rinsed with cold water and packaged in sealed bags of low density polyethylene films with different thickness(22, 36, $63\;{\mu}m$), and stored at $10^{\circ}C$ for 18 days. Thickness of polyethylene film was a significant factor for microorganisms populations and sensory attributes. Mesophilic aerobic bacterial count after 13 days for the control, packed in punched film bags, was $3.07{\times}10^6}$ CFU/g, while those for samples in hermetically sealed bags ranged only $1.74{\sim}2.02{\times}10^5}$ CFU/g. Gas composition within the sealed packages changed from normal air to about $1.3{\sim}5.4%\;O_2$ and $4.0{\sim}8.0%\;CO_2$ after 13 days of storage. Particularly, the visual sensory quality of cut green onion samples was retained better in polyethylene film bags of $63\;{\mu}m$ thickness(gas transmission rate: 600 $O_2\;mL/day{\cdot}m^2{\cdot}atm;\;2,500\;CO_2\;mL/day{\cdot}m^2{\cdot}atm$) than in the others.