• Title/Summary/Keyword: Falling bacteria

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Changes in Quality of Soybean Curd Residue as Affected by Different Drying Methods (건조방법에 따른 비지의 품질변화)

  • 김동수;설명훈;김현대
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.3
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    • pp.453-459
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    • 1996
  • This study was carried out to determine the changes in quality during the drying process and the optimum drying condition for utilizing soybean curd residue. The quality criteria for soybean curd residue were acid value, peroxide value, fatty acid composition and microbial concentration. The acid values of soybean curd residue were 7.5, 4.5 and 5.9 KOH mg/g upon 12 hour drying with open-air sun, ambient-air blast and warm-air blast, respectively. The numbers of total aerobic bacteria and molds increased remarkably during drying with open-air sunlight, ambient-air blast and warm-air blast except for hot air blast. Among different drying methods, the hot air blast drying(1kg of sample) was the most effective methods, which completed in three hours. Also, the drying method demonstrated a typical drying curve ; settling down, constant rate drying and falling rate drying period were shown within one hour, from one and three hours and after three hours, respectively. Moreover, there was significant variation in the constant drying period for the quality of soybean curd residue.

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Performance Improvement of Simple Bacteria Cooperative Optimization through Rank-based Perturbation (등급기준 교란을 통한 단순 박테리아협동 최적화의 성능향상)

  • Jung, Sung-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.12
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    • pp.23-31
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    • 2011
  • The simple bacteria cooperative optimization (sBCO) algorithm that we developed as one of optimization algorithms has shown relatively good performances, but their performances were limited by step-by-step movement of individuals at a time. In order to solve this problem, we proposed a new method that assigned a speed to each individual according to its rank and it was confirmed that it improved the performances of sBCO in some degree. In addition to the assigning of speed to the individuals, we employed a new mutation operation that most existing evolutionary algorithms used in order to enhance the performances of sBCO in this paper. A specific percent of bad individuals are mutated within an area that is proportion to the rank of the individual in the mutation operation. That is, Gaussian noise of large standard deviation is added as the fitness of individuals is low. From this, the probability that the individuals with lower ranks can be located far from its parent will be increased. This causes that the probability of falling into local optimum areas is decreased and the probability of fast escaping the local optimum areas is increased. From experimental results with four function optimization problems, we showed that the performances of sBCO with mutation operation and individual speed were increased. If the optimization function is quite complex, however, the performances are not always better. We should devise a new method for solving this problem as a further work.

Weathering and Deterioration Diagnosis for Conservation Sciences of Stone Pagoda in the Bunhwangsa Temple,Gyeongju, Korea (경주 분황사 모전석탁의 암석학적 풍화와 보존과학적 훼손도 진단)

  • Yi, Jeong-Eun;Lee, Chan-Hee;Lee, Myeong-Seong;Kim, Young-Taek
    • 한국문화재보존과학회:학술대회논문집
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    • 2004.10a
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    • pp.92-100
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    • 2004
  • The host rocks of brick-shaped stone pagoda in the Bunhwangsa temple are lots of kinds andesitic rocks, which has gone through mechanical and chemical weathering. As the overall observation, the pagoda is serious damages by air pollutants, and the northeast parts show the much advanced state of turning white, while the southeast parts are heavily cracked in the materials. The rocks of brick-shaped pagoda body are in a relatively stable condition of weathering and damage except for the abrasion and cracks of the corners. The rocks of the pagoda roof suffer from more symptoms including multiple peel-offs, exfoliation, cracks forming round lines, and falling off stone pieces. The pagoda roof rocks are dominated by the thriving leafy lichens and mosses, especially, there are higher plants (selaginella involvens, dandelions) taking root actively between the brick stones and content mortar. There are even light gray precipitates like stalactites between the rocks of the body, In particular, the 1st and 2nd floor in the east side and the body parts in the north side are the most serious. Their major minerals are calcite, gypsum and clay minerals. The rocks of the stylobate and the tabernacle in all the four directions are composed mainly of granitic rocks. The materials consisting of the tabernacles show the severe splits and distortion, which causes the structural instability. The stylobate rocks are heavily contaminated by some weeds with the often marks of inorganic contamination by secondary hydroxides. The central part of the east stylobate has been sinking, while that of the 1st floor west stylobate is protruded nesting a line of cracks. Accordingly, the inside of the tabernacle is always humid with the constant introduction of rainwater. The stone lion standing in the southeast and northeast side are alkali granite, while that in the southwest and northwest lithic tuff. Each of the stone lion also coated with various colored lichens, mosses, algae, bacteria and bryophyte. The external materials of the pagoda have deteriorated the functions of the rocks and made the loss, falling off, and biological contamination even worse due to the surface weathering. Thus it's urgent to come up with scientific restoration and conservation measures through clinical tests.

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A new Type of the Doma (Cutting Board) for Kimchi (김치용 도마의 새로운 형태)

  • Kim, Joong-Man
    • Journal of the Korean Society of Food Culture
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    • v.1 no.3
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    • pp.211-218
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    • 1986
  • The doma (cutting board) is an essential kitchen utensil. The general doma used at present is not sultable for cutting kimchi-like juicy foods, because It is a nat flat structure. Kimchi juice contains vitamins, organle acids, and lactic acid bacteria, and inhibits Oxidation of flavor of kimchi. In addition, if the juice flows down on the doma during cutting the doma work-table and kimchi bottom is contaminated. In this studies a new type of doma for kimchi. was made in order to minimize the Juice Iou during cutting. This new one baa a two-dimensional function of low due to length slope face and slanted gutter of width. No this new type has been developed worldwide, as far as the present writer is aware. The new one has various effectivenesses: minimixing loss of kimchi juice and contamination of doma work-table and kitchen bottom by kimchi juice, saving water and time to water contaminated cutting board, work-table and diahtowel (hangju). preventing round from falling down frorr doma duing cutting, decreasing damage of cutting the user's finger, cutting by the fixed size and shape. Draining and drying is easy and it is convenient to cut all juicy food.

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Seasonal Distribution of Bacterial Populations and Escherichia coli O157 at Hanwoo Cattle Feedlots in Gyeongsangbuk-do (경상북도 한우축사에서의 계절별 세균 및 Escherichia coli O157 분포 변화)

  • Khang, Yong-Ho;Kang, Moon-Sook
    • Korean Journal of Microbiology
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    • v.45 no.2
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    • pp.222-227
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    • 2009
  • The seasonal variation of bacterial populations in the Korean cattle (Hanwoo) feedlots dispersed in the 20 cities of Gyeongsangbuk-do, Korea, was monitored for two years (2006 and 2007) to provide quantitative criteria for good agricultural management. Outside the feedlots, the average falling bacterial populations of the air were $3{\pm}1$ CFU/$cm^2\cdot15$ min (n=63) in a year. Inside the feedlots, the average falling bacterial populations of the air were $8{\pm}1$ CFU/$cm^2\cdot15$ min (n=63) in the spring, $16{\pm}2$ CFU/$cm^2\cdot15$ min (n=69) in the summer, $7{\pm}2$ CFU/$cm^2\cdot15$ min (n=69) in the autumn, and $6{\pm}1$ CFU/$cm^2\cdot15$ min (n=70) in the winter. Without using the summer data, the average falling bacterial population of the air was $7{\pm}1$ CFU/$cm^2\cdot15$ min, which was not statistically significant (P=0.37). The average bacterial populations in the cattle drinking water of the cattle feedlots were $4,710{\pm}780$ CFU/ml (n=65) in the spring, $10,430{\pm}1170$ CFU/ml (n=65) in the summer, $4,820{\pm}700$ CFU/ml (n=64) in the autumn, and $2,510{\pm}530$ CFU/ml (n=64) in the winter. Without using the summer data, the average bacterial population of the drinking water was $4,000{\pm}400$ CFU/ml, which was statistically significant (P=0.027). The average frequency of Escherichia coli O157 inside the feedlots was 5% (n=65) in the spring, 72% (n=65) in the summer, 67% (n=66) in the autumn, and 29% (n=66) in the winter on the basis of soil samples of the year 2007. The results indicate that most of the Escherichia coli O157 strains distributed in the summer and autumn was disappeared in the spring through the cold weather of the winter.

Effects of High Pressure on Quality Stability of Fresh Fruit Puree and Vegetable Extracts During Storage (고압처리가 신선 과채음료의 저장기간 중 품질 안정성에 미치는 영향)

  • Kim, Young-Kyung;Lee, Yong-Hyun;Iwahashi, Yumiko
    • Food Science and Preservation
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    • v.17 no.2
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    • pp.190-195
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    • 2010
  • Pressure, used as a minimal processing technology in the food industry, is a valuable tool ensuring microbiologically safe, shelf-stable fruit and vegetable production. Pressure could be used to deliver a greater variety of minimally processed products, as demanded by today's consumers. Weevaluated the effect of <400 MPa pressure, applied during chilling, on fresh fruit purees (strawberry, kiwi, aloe, and pomegranate) and vegetable extracts (from carrot and spinach) during cold storage (<$10^{\circ}C$) for 15-20 days. Samples were prepared in a processing facility in which total plate counts of falling and floating bacteria were controlled at $1{\times}100-10^1$ CFU/plate and $1{\times}10^2-10^3$ $CFU/m^3$ under conditions of $21-25^{\circ}C$ and 55-60% relative humidity. The aerobic plate counts of raw materials were less than $1{\times}10^3$ CFU/g. Evaluation parameters included microbiological safety, vitamin content, and sensory qualities. Although the overall quality of non-treated samples deteriorated with storage time at $10^{\circ}C$, samples pressurized at 250-350 MPa at $5-7^{\circ}C$ for 10 min showed less change, with no significant difference in microbiological safety, vitamin content, or sensory quality. The use of pressure extended the shelf-life during storage at $10^{\circ}C$.

Analysis and Improvement Measures on the Status of the Installation and Operation of Facilities for Recycling Food Waste into Compost (음식물쓰레기 퇴비화시설의 설치 및 운영 현황분석 및 개선방안)

  • Ryu, Ji-Young;Kong, Kyu-Sik;Shin, Dae-Yewn;Phae, Chae-Gun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.12 no.3
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    • pp.95-111
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    • 2004
  • This research sought to determine the status of the installation and operation of composting facilities of domestic public resource-making facilities and come up with corresponding improvement measures. The composting facilities were the most extensively installed of related facilities with over a 0.5 ton treated volume per day. The monthly and yearly carry-in volume of food waste were found to stand at 1,101.7 tons per day and 930.9 tons per day, thus falling short of the average planned volume of 1,270.9 tons. Many composting facilities, which were installed in areas for which factory registration were not approved, did not get approvals. Composting facilities underwent operation stoppage mainly due to faulty fermentation and crushing equipment. Mainly metals contained in food waste caused faults to the crushing equipment, thus requiring a facility designing against faults and corrosion. The initial water content was found to stand at 50-60%, thus complying with the requirement. However, since the composting food waste had an appropriate mixture of sawdust, food waste, and returned compost, it should meet the initial conditions. For fermentation facilities, the duration time for fermentation was 15 days, and post-fermentation tanks required 21 days of duration time, thus establishing the minimum criteria. However, some facilities did not meet the requirements, taking more time in decomposition, thus suggesting a need to determine the duration time according to facilities. In composting food waste, microorganism-based thermal oxidizer-operated fermentation tanks should be used to ensure an economic operation. On the contrary, 14 out of 25 survey targets heated fermentation tanks in any form. These thermal facilities contain the growth of bacteria, lowering chemical reaction in composting; thus composting facilities should be basically designed to use microorganism-based thermal oxidizers in drying water. An average daily volume of food waste and supplementary materials that was injected in producing compost was 22.8 tons. This volume produced 7.3 tons of compost per day, decreasing 68%. Properties of produced compost were analyzed by its color, absence or presence of remaining decomposition heat, and smell, to assess the quality. As a result, the composting process was not properly installed nor operated in about 50% of composting facilities. Compost should be produced to be soil-friendly.

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