• 한국미생물·생명공학회지
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• 제24권3호
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• pp.376-379
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• 1996

Cane molasses, the most widely used carbon source for the industrial fermentation of L-lysine, usually contains a high concentration of calcium ions which tend to cause scaling problem in the recovery process. To remove the calcium ions, cane molasses was pretrea ted with sulfuric acid by adjusting the pH to 2.5-3.5. When the pretreated solution was directly heat-sterilized and used in the fermentation, a significant reduction in L-lysine production was observed. In this paper, we proved that sucrose is a superior substrate for L-lysine fermentation to that of glucose or fructose and that the above-mentioned decrease of L-lysine production was caused by the hydrolysis of sucrose in the molasses when the molasses was heat-sterilized at a low pH. The problem was overcome by adjusting the pH of molasses to neutral before sterilization.

• Journal of Pharmaceutical Investigation
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• 제6권1호
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• pp.1-13
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• 1976

• Fisheries and Aquatic Sciences
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• 제18권1호
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• pp.7-11
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• 2015

The influence of spice (cinnamon, allspice, black pepper)-oil extract on canned seafood quality was studied. During the processing of canned seafood, the substitution of spice-oil extract for vegetable oil (refined sunflower, corn, soybean and olive oil) resulted in a decrease in the heat resistance of spore microorganisms, making it possible to reduce the duration of sterilization for canned food to 5-10 min at $115^{\circ}C$. This reduction in the sterilization duration of canned seafood with spice-oil extract inhibited residual microflora in the product, thus reducing the deleterious effect of heating on the main food compounds while preserving protein digestibility.

• 생약학회지
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• 제36권3호통권142호
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• pp.220-223
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• 2005

The purposes of this study was to develop the best one among the methods using dry heat, gamma irradiation and alcohol gas, to sterilize Scutellariae Radix selected based on high frequency of circulation between merchants and high susceptibility to microbial contamination, through comparing these methods in terms of the followings; ⅰ) the efficacy of sterilization in comparison with cost, and ⅱ)the alteration of chemical components of these herbal medicines. The results of this study will be taken advantage of establishment of the maximum limit of microorganism contaminated in herbal medicines. From the results of this study we conclude the followings: ⅰ) The sterilizing method using dry heat may be inappropriate, because it seriously changed their color and morphology which is an essential criterion to estimate a measure of quality between merchants and consumers, although it effectively got rid of contaminated microorganism and did not alter major components, baicalin; ⅱ) The sterilizing method using gamma irradiation may be appropriate, because it showed a strong sterilizing effect, and no alteration of chemical components, color and morphology; ⅲ)The sterilizing method using alcohol gas may also be appropriate, because it had a similar effects as in the case of gamma irradiation. Collectively, we suggest that appropriate sterilizing methods to guarantee the microbial quality of this herbal medicine may be those using gamma irradiation and alcohol gas.

• Journal of Dairy Science and Biotechnology
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• 제35권2호
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• pp.121-133
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• 2017

A small amount of milk is sold as 'untreated' or raw in the US; the two most commonly used heat-treatments for milk sold in retail markets are pasteurization (LTLT, low-temperature long time; HTST, high-temperature short time) and sterilization (UHT, ultra-high temperature). These treatments extend the shelf life of milk. The main purpose of heat treatment is to reduce pathogenic and perishable microbial populations, inactivate enzymes, and minimize chemical reactions and physical changes. Milk UHT processing combined with aseptic packaging has been introduced to produce shelf-stable products with less chemical damage than sterile milk in containers. Two basic principles of UHT treatment distinguish this method from in-container sterilization. First, for the same germicidal effect, HTST treatments (as in UHT) use less chemicals than cold-long treatment (as in in-container sterilization). This is because Q10, the relative change in the reaction rate with a temperature change of $10^{\circ}C$, is lower than the chemical change during bacterial killing. Based on Q10 values of 3 and 10, the chemical change at $145^{\circ}C$ for the same germicidal effect is only 2.7% at $115^{\circ}C$. The second principle is that the need to inactivate thermophilic bacterial spores (Bacillus cereus and Clostridium perfringens, etc.) determines the minimum time and temperature, while determining the maximum time and temperature at which undesirable chemical changes such as undesirable flavors, color changes, and vitamin breakdown should be minimized.

• 한국식품과학회지
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• 제15권3호
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• pp.282-286
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• 1983

통조림 살균에서 에너지의 효율적인 사용을 위하여 열전달형태, 살균온도, 가공공관, 살균방법등의 요인에 따른 에너지 소비를 검토한 바 고온(高溫)에서 소형관형으로 살균할 때가 적은 에너지가 소비되고 있으며, 이러한 차이는 대류형(對流型) 열전달식품(熱傳達食品)보다 전도형(傳導型) 열전달식품(熱傳達食品)의 살균(殺菌)에 현저하였다. 열수살균으로는 증기살균에 비해 전도형 식품의 살균에 적은 에너지를 소비하였으나, 대류형 식품에서는 효과적이지 못하였다. 본 실험에서의 여러 조건별 에너지 소비 data는 현장에서의 에너지 소비예측, 에너지 사용설계 등의 여러목적에 적용될 수 있는 것으로 판단된다.

• 한국식품과학회지
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• 제32권2호
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• pp.356-362
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• 2000

7개의 전극을 직렬로 배열한 다중전극 고전압펄스 전기장(PEF) 처리장치를 사용하여 전기장 세기와 주파수를 달리한 square wave 펄스(너비 $1\;{\mu}s$)로 약주의 연속 살균을 시도하였다. 살균 전 약주의 총균수는 $1.88{\times}10^3{\sim}2.13{\times}10^4\;CFU/mL$, 효모는 $1.72{\times}10^3{\sim}2.39{\times}10^4\;CFU/mL$, 젖산균은 $1.55{\times}10^3{\sim}2.85{\times}10^4\;CFU/mL$이었다. 약주를 유량 1 mL/s의 속도로 PEF장치에 투입하여 처리한 결과 미생물 사멸기구는 1차반응으로 해석 될 수 있었고, 주파수 및 전기장세기가 증가함에 따라 살균율이 높아졌다. $D_{Hz}$값 및 $D_{PEF}$값은 전기장 세기가 증가함에 따라 감소하였으며, 효모는 세균에 비하여 낮은 값을 보였다. 젖산균은 30 kV/cm 이하의 전기장에서는 일반 호기성 세균에 비하여 낮은 $D_{PEF}$값을 보였으나, 40 kV/cm 이상에서는 높은 $D_{PEF}$값을 나타냈다. 미생물 종류별 $Z_{PEF}$값은 일반 호기성 세균 39.4 kV/cm 젖산균 49.3 kV/cm, 효모 47.6 kV/cm로 일반 호기성 세균의 전기장세기에 대한 의존성이 가장 큰 것으로 나타났다. PEF처리에 의한 약주의 색택 변화는 열처리에 비하여 미미하였으며, PEF살균 약주의 품질은 가열살균 약주에 비하여 월등히 우수하였다. 약주를 본 연구에서 사용한 PEF장치에 2회 통과시킬 경우 상업적 살균이 달성되었다.

• KSBB Journal
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• 제13권6호
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• pp.724-729
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• 1998

To develop a large scale countercurrent single pass heat exchanger for continuous transportation and sterilization of soybean paste, microflora and color value of sterilized soybean paste were examined at various sterile condition. Aerobes, anaerobes, molds, yeasts and lactic acid bacteria were 5.1 x 107 CFU/g, 7.1 x 107 CFU/g, 2.6 x 105 CFU/g, 4.3 x 106 CFU/g, 1.3 x 107 CFU/g, respectively in raw soybean paste. In gold band ampoule test, aerobes and anaerobes of soybean paste were viable up to 90$^{\circ}C$, but become unviable at 100$^{\circ}C$. Molds decreased rapidly and yeasts decreased slowly from 70$^{\circ}C$. Lactic acid bacteria were unviable at 60$^{\circ}C$ within 10 min. In color test, Hunter L, a, and b values of soybean paste were 50.2, +5.6, and +17.8, respectively. After heating in polyethylene film bag at 80$^{\circ}C$, Hunter values were not so much changed and become 50.2, +4.7, and +19.7, respectively. The micorflora and color of soybean paste sterilized in a large scale heat exchanger system resulted in very similar to those of gold band ampoule and polyethylene film bag by effective heat transfer.

• 약학회지
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• 제7권2_3호
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• pp.42-50
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• 1963

The destruction rate of microorganisms by heat follows the first order reaction. In this experiments, the calculated sterilization velocity constants of Escherichia Coli are 1.97 * $10^{-2}min^{-1}.(45{\deg}$ C), 9.53 * $10^{-2}min^{-1}.(55{\deg}$ C) and $1.858min^{-1}.(70{\deg}$ C), 2.89 * $10^{-2}min^{-1}.(80{\deg}$ C), 1.32 * $10^{-1}min^{-1}.(90{\deg}$ C), 2.87 * $10^{-1}min^{-1}.(95{\deg}$ C), 7.91 * $10^{-1}min^{-1}.(100{\deg}$ C) and $1.777min^{-1}.(105{\deg}$ C). In the results, the activation energy of E. Coli is 62.0 Cal $mole^{-1}.(45{\deg}-60-{\deg})$, that of B. Subtilis are 17.8 Cal $mole^{-1}(60{\deg}-80{\deg}$ C) and 47.1 Cal $mole^{-1}(90{\deg}-105{\deg}$ C).

• 한국토양비료학회지
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• 제23권2호
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• pp.146-151
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• 1990

Rhizobium균을 이용하여 근류균 접종제를 생산하기 위한 기초연구로 우수한 증량제(carrier material)를 선발하고, 근류균의 접종량, carrier의 숙성 및 보존온도, 멸균조건등 근류균 접종제 생산을 위한 각종 조건을 확립하기 위하여 실험한 결과는 다음과 같다. 1. 근류균 접종제 생산을 위한 carrier material source로는 퍼라이트 및 토탄이 우수한 것으로 나타났다. 2. 근류균의 접종량(inoculum size)에 따른 경시적 생존율은 접종초기 $10^4cells/g$ 이하의 균주를 접종하여도 1~2주후에는 $5{\times}10^8cells/g$로 증가하여 $10^8cells/g$ 접종구와 비슷한 균수를 나타내었다. 3. Carrier의 숙성 및 보존온도에 따른 근류균의 경시적 생존율은 특별한 보온이나 냉장시설없이 실온($20^{\circ}C$) 보존에서도 $10^9cells/g$의 높은 균수가 12주째까지 유지되었다. 4. Carrier의 멸균방법에 따른 근류균의 경시적 생존율은 가압습열멸균 처리구에서 생존율이 가장 양호하였으나 각 처리에 따른 큰 차이는 볼 수 없었고, 특히 퍼라이트의 경우에는 멸균처리없이도 12주째 까지 $10^9cells/g$ 이상의 높은 균수를 유지하였다.