• 제목/요약/키워드: sterilization method

검색결과 277건 처리시간 0.023초

딸기주 발효를 위한 효모 선발과 살균 방법의 비교 및 발효 중 이화학적 특성의 변화 (Yeast Selection and Comparison of Sterilization Method for Making Strawberry Wine and Changes of Physicochemical Characteristics during Its Fermentation)

  • 정은정;김용석;정도연;신동화
    • 한국식품과학회지
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    • 제38권5호
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    • pp.642-647
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    • 2006
  • 저알콜 딸기발효주 제조에 필요한 최적발효조건 설정을 위하여 발효에 적합한 효모를 선발하고, 딸기착즙액의 살균방법을 비교하였으며, 발효 중 이화학적 특성의 변화를 조사하였다. 딸기는 매향과 육보 품종을 사용하였으며, 이들은 각각 pH 3.77 및 3.69, 가용성 고형분 함량 9.8 및 9.3%, 총산 함량 0.74 및 0.69%의 이화학적 특성을 가졌다. 6종의 효모를 대상으로 발효시험을 한 결과 Wg-15 와 Sc-51 효모의 알콜생성능력이 우수하였다. 딸기에 있는 잡균을 제거하기 위하여 $K_2S_2O_5$(200 ppm) 및 열처리($85^{\circ}C$, 10 min) 시험을 비교한 결과 알콜생성량(7.1-7.2%)과 가용성 고형분 함량(5.6-5.8%)이 비슷하였으며, Wg-15와 Sc-51 효모 사이에 유의적 차이는 관찰되지 않았고, 발효주의 향에서 열처리구가 약간 좋은 것으로 나타났다. 초기 가용성 고형분 함량을 12, 14 및 16%로 조정하여 $26^{\circ}C$ 에서 8일간 발효한 결과 발효 2일째 까지 대부분의 알콜이 생성되었으며, 알콜함량은 각각 5.1 6.0-6.2, 7.5-7.7%, 가용성 고형분 함량은 각각 3.9-4.3, 4.1-4.3, 5.0-5.3%를 나타냈고, Wg-15 와 Sc-51 효모 사이에 차이는 관찰되지 않았다. 알콜함량 7% 정도의 딸기발효주를 제조하기 위해서는 매향 또는 육보 품종을 사용하여 설탕으로 가용성 고형분 함량을 16%로 보당하고, 착즙액에 대해 $85^{\circ}C$에서 10min 열처리한 후 Wg-15 또는 Sc-51 효모를 사용하여 $26^{\circ}C$에서 8일간 발효하는 것이 바람직하였다.

가열, 고압, 방사선 처리된 빙핵활성세균의 활성 및 물의 동결특성에 미치는 영향 (Ice Nucleating Activities of Ice Nucleation-Active Bacteria Sterilized with Heat, Pressure and Irradiation , and Their Thermophysical Effects on Water)

  • 김현정;박지용
    • 한국식품과학회지
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    • 제29권2호
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    • pp.326-336
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    • 1997
  • INP를 포함한 빙핵활성세균을 식품 가공 단계에 직접 이용하기 위해 빙핵활성을 최대한 유지시키면서 완전 살균하는 방법을 찾기 위해 가열, 고압, 방사선으로 처리한 후 생균수 및 빙핵활성을 측정하였다. 균주는 Pseudomonas syringae, Xanthomonas campestris와 INP유전자를 포함한 plasmid가 재조합된 Escherichia coli JM109/pEIN229, Gluconobacter oxydans/pKIN230를 사용하였다. 빙핵활성을 T90 (drop의 90%가 어는 온도)으로 나타내었을 때 방사선 조사시 $0.3^{\circ}C{\sim}0.7^{\circ}C$, 초고압 처리시 $1^{\circ}C{\sim}2^{\circ}C$, 가열 처리시 $4^{\circ}C{\sim}7^{\circ}C$가 감소하여 방사선 조사에 의한 살균시 빙핵활성의 감소가 가장 적은 것으로 나타났다. 각 살균점에서의 cumulative ice nucleation activity spectra를 측정한 결과 A부류의 빙핵($-5^{\circ}C$ 이상에서 빙핵으로 작용)의 수는 방사선처리시 거의 감소가 없었으며 초고압처리시 90% 이상 감소하였으며 가열처리시 존재하지 않았다. 증류수에 방사선조사로 살균된 빙핵활성세균을 첨가한 후 DSC를 이용해 thermogram을 얻었다. 빙핵활성세균을 첨가하지 않은 증류수보다 $11^{\circ}C{\sim}15^{\circ}C$ 정도 높은 온도에서 발열 피크가 형성되기 시작했으나 흡열 피크는 큰 차이를 보이지 않았으며, 발열량 및 흡열량은 감소했다. 한편, DSC를 이용해 측정된 빙핵활성은 drop freezing method에 의해 측정된 값과 높은 연관성$(R^{2}>0.993,\;p<0.0001)$을 보여 간편하고 정확한 빙핵활성 측정법으로의 사용 가능성을 제시했다.

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레이저 회절 측정기를 이용한 벤츄리 캐비테이션에서의 마이크로버블 발생 특성 연구 (Study on Micro-bubble Generation Characteristics in Venturi Cavitation using Laser Diffractometer)

  • 임윤규;양해정;김영일
    • 드라이브 ㆍ 컨트롤
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    • 제16권1호
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    • pp.1-6
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    • 2019
  • The use of micro bubbles in industrial fields has been increasing in the recent years., particularly micro-bubble sterilization and water purification effects. Various methods have been developed for the generation of micro-bubbles. Depending on the method of generating bubbles, the micro-bubbles can be roughly classified into saturation molding, cavitation and rotation flow types. The objective of this study was to use ventilated tube type as a method of generating micro-bubbles in order to purify large amount of water quality such as lakes and reservoirs. This method shows a difference in efficiency in which micro-bubbles are generated depending on the contact ratio of gas to liquid. The study also investigated the optimal gas liquid contact ratio by applying various orifice methods and investigated the optimum condition of micro-bubble generation by gas Based on this, a technology to develop a micro-bubble generator with a venturi type nozzle shape that has a high water purification effect was developed.

출력 커패시터가 없는 위상천이 풀브릿지 컨버터의 전류 전향 보상을 이용한 출력 전압 제어 기법 (Output Voltage Control Technique Using Current Forward Compensation for Phase Shifted Full Bridge Converter Without Output Capacitor)

  • 신유승;백승우;김학원;조관열;강정원
    • 전력전자학회논문지
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    • 제27권1호
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    • pp.40-47
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    • 2022
  • At present, the low-voltage, high-current type power supply is mainly used for effective sterilization in the ballast water treatment system. Research on PSFB converters without output capacitors has been ongoing. Such converters effectively treat ballast water without a separate disinfectant through electric pulses by applying a pulse-type power to the output electrode without an output capacitor. However, in the case of the pulse-type electrolysis treatment method, voltage overshoot can occur due to abrupt voltage fluctuations when the load changes, resulting in circuit reliability problems because of the output capacitorless system. Therefore, a new voltage control algorithm is required. In this paper, we will discuss voltage control for pulsed electrolysis topology without an output capacitor. The proposed voltage control method has been verified using Simulation and experiment. The usefulness of the proposed control method has been proven by the experimental results.

Tracheal Foreign Body by Accidental Fracture of Tracheostomy Tube

  • 유재철;장문영;정영호;진홍률
    • 대한기관식도과학회지
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    • 제13권2호
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    • pp.68-71
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    • 2007
  • Fractured tracheostomy tube presenting as foreign body in the tracheobronchial tree is very rare. Authors experienced a case of broken tracheostomy tube presenting as a foreign body in the trachea, which was removed with the help of flexible bronchoscope. A few causes could be suggested for the tube break: aging and deterioration of the tube with repeated use, a flaw of the tube in the manufacturing process, and a wrong sterilization.method causing weakness of the tube. We report this case with brief literature review.

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Microwave를 이용한 배지 융해와 공기 제거 (Usefulness of microwave to melt rehydrated media and to remove oxygen from anaerobic tube media)

  • 정윤섭;이귀녕;이삼열
    • 미생물학회지
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    • 제18권3호
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    • pp.148-152
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    • 1980
  • The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

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식품조사(食品照射) 실용화(實用化)에 대한 배경(背景)과 전망(展望) (Background and Prospect for the Commercialization of Food Irradiation)

  • 권중호
    • 한국식품영양과학회지
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    • 제14권1호
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    • pp.88-94
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    • 1985
  • Food irradiation is increasingly recognized as the sole viable alternative to traditional method of food preservation in terms of reducing the overall quantity of spoiled food, reducing energy used in food storage, and reducing reliance on chemicals known to be hazardous but currently required for disinfestation. Irradiation with ionizing radiation can be applied in the fields of sprout inhibition, disinfestation of insects, sterilization, delay of ripening, and improvement of organoleptic properties in food. In order to back up the commercialization of food irradiation in Korea, this review not only dealt with the international background for food irradiation and wholesomeness of irradiated food, but also evaluated economic feasibility of irradiated food, irradiation facilities, and domestic status of food irradiation studies.

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우유 및 유제품의 열처리 및 펄스 전기장 살균 최근 연구 개발 동향 (Recent Research on and Development of Thermal and Pulsed Electric Field Systems for Pasteurization of Milk and Milk Products)

  • 강신호;신용국
    • Journal of Dairy Science and Biotechnology
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    • 제32권1호
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    • pp.31-36
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    • 2014
  • Thermal pasteurization has been effectively used for decades as a method to extend the shelf life of milk and to inactivate any pathogenic bacteria that it may contain; however, it can negatively affect the nutritional properties of milk. In recent years, the food industry has sought new, less aggressive technologies that affect food freshness and its nutritive and health benefits less significantly. Various means have been used to extend the shelf life of dairy foods, such as high-pressure processing, irradiation, ohmic heating, and pulsed electric field (PEF) technologies. Of these, PEF technologies are potential alternatives to traditional thermal milk pasteurization, owing to their advantages in minimizing sensory and nutritional damage. In this review, we have primarily focused on the feasibility of applying PEF technologies to the sterilization of dairy products and briefly discussed whether they should be adopted for use in the dairy beverage industry in the future.

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The Management of Delayed Post-Pneumonectomy Broncho-Pleural Fistula and Esophago-Pleural Fistula

  • Noh, Dongsub;Park, Chang-Kwon
    • Journal of Chest Surgery
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    • 제49권2호
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    • pp.138-140
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    • 2016
  • Broncho-pleural fistula (BPF) and esophago-pleural fistula (EPF) after pulmonary resection are challenging to manage. BPF is controlled by irrigation and sterilization, but such therapy is not sufficient to promote closure of EPF, which usually requires surgical management. However, it is generally difficult to select an appropriate surgical method for closure of BPF and EPF. Here, we report a case of concomitant BPF and EPF after left completion pneumonectomy, in which both fistulas were closed through a right thoracotomy.

콩의 오존처리가 두부의 저장성에 미치는 영향 (Shelf-Life of Soybean Curd Prepared with Ozone-treated Soybeans)

  • 김일두;박미자
    • 한국식품저장유통학회지
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    • 제5권1호
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    • pp.73-80
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    • 1998
  • Shelf-life of soybean curd prepared with ozone-treated soybeans investigated on pH, acidity, sour taste, slime formation during storage at 3$0^{\circ}C$. Total Plate counts of raw soybeans showed about log 7.0 CFU/g before ozone treatment. The sterilization efficiency of raw soybeans showed the most effective in 0.5ppm of aqueous ozone treatment at 4$^{\circ}C$ for 90 minutes. Raw soybeans were treated with ozone by different methods; (1) Ozone treatment for 90 + 90 minutes (first 3.5~5 hours and later 8.5~10 hours) of 10 hours during soaking in aqueous solutions at 4$^{\circ}C$ (OW). (2) Ozone treatment by exposure first to 30ppm of gaseous ozone for 90 minutes and then allied to OW method (GO+OW). The log reduction of raw soybeans treated by OW and GO+OW methods showed 3.72 and 4.15, respectively. Soybean curd prepared with OW and GO+OW-treated soybeans kept the shelf-life of 4 and 5.5 days at 3$0^{\circ}C$, respectively, but, that without ozone treatment spoiled at me day.

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