• 제목/요약/키워드: heat treatment processing

검색결과 603건 처리시간 0.025초

식품 첨가물이 Listeria monocytogenes H-12의 내열성에 미치는 영향 및 오염된 조리기구 제균 (Effect of Food Additives on Heat Sensitivity of Listeria monocytogenes H-12 and Decontamination of Kitchen Utensils)

  • 이희정;이태식;손광태;변한석;김지회;박정흠;박미정
    • 한국수산과학회지
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    • 제33권6호
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    • pp.524-528
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    • 2000
  • 식품중에 오염된 Listeria monocytogenes의 열감수성에 미치는 각종 첨가물의 영향과 식품의 처리 가공시에 수반되는 조리기구 수세나 염소, 자외선, 열탕 등 각종 소독처리의 효율성을 확인하였다. 키토산, 솔빈산칼륨 둥은 시험균주 L. monocytogenes H-12의 열 감수성 증대에 유의할 만한 영향을 미치지 못하였으나, 명태 연육에 중합인산염을 $1{\%}$ 첨가할 경우 시험균주의 열감수성은 뚜렷히 증가되었다. 시험균주 L. monocytogenes H-12가 $약 10^4{\~}10^5/cm^2$ 되도록 오염시킨 나무, 플라스틱, 스테인레스 재질의 도마를 흐르는 수도수로 세척하였을 때 스테인레스 도마나 플라스틱 도마의 경우 각각 10초 및 1분 후에는 균이 검출되지 않았으나, 나무 도마에서는 거의 제균효과가 없었다. 스테인레스 및 플라스틱 재질의 도마를 $5{\~}50 ppm$의 염소용액에 10초간 침지하고 수세할 경우 오염균의 제거가 가능하였으나, 나무 도마의 경우 100ppm 염소용액으로 처리하여도 균 수의 감소는 거의 없었다. 15W의 자외선을 30cm 거리에서 시험균주로 오염된 각 재질의 도마에 조사할 경우 스테인레스 및 플라스틱 도마의 경우 5분간 조사 후에는 균이 검출되지 않았으나, 나무 도마에서는 60분 처리 후에도 균이 검출되었다. 각종재질의 조리용 도마에 오염된 시험균주 L. monocytogenes H-12의 열탕처리에 의한 제균조건은 $70^{\circ}C$, 10초 이상으로 확인되었다.

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오스템퍼드 구상흑연주철의 Processing Window에 미치는 오스테나이징 조건 및 주석의 영향 (Effects of Austenitization and Sn Addition on Processing Window of Austempered Cast-iron)

  • 권민영;백승훈;윤동근;김민준;김동주;권해욱;고영건
    • 소성∙가공
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    • 제30권1호
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    • pp.22-26
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    • 2021
  • The present study demonstrated the effects of processing variable and alloying elements on the processing window of austempered cast iron, one of the heat-treatable cast irons, in order to elucidate the relation between heat treatment and microstructure in terms of time and temperature. Such microstructure is strongly affected by austenitizing conditions and alloying elements. The size of processing window tends to increase initially with increasing austenitizing temperature from 1123 to 1173 K, followed by a decline in the reverse direction between 1173 and 1223 K. Thus, the optimized processing window with large frame was found at an austenitizing temperature of 1173 K. To determine the effect of Sn addition, the processing window in the sample was created by the addition of 0.08 wt.% Sn, which appeared larger than that without Sn and with 0.06 wt.% Sn.

열처리에 의한 작약의 Paeoniflorin 함량 변화 (Changes of Paeoniflorin Content in Peony Roots by Heat-treatment)

  • 김태강;김광중
    • 한국식품저장유통학회지
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    • 제4권1호
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    • pp.69-75
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    • 1997
  • Peony is a medicinal herb which have utilized widely as chineses medicine. The paeoniflorin is the predominant component In peony root, monoterpene glucoside containing pinane structure. The effective components were extracted with the cold water from the intact peony roots, and effectively extracted with 70% ethanol from the dry powder of peony roots. The changes of paeoniflorin contents were investigated during the drying process of peony roots and processing of peony extract by the heat-treatment. Air-drying was the best condition for the preservation of paeoniflorin content among the drying processes of peony roots. But convective drying at 6$0^{\circ}C$ was recommended for the drying process of peony roots in large scale. The paeoniflorin in peony extracts was not destroyed by the treatment at 6$0^{\circ}C$ and 8$0^{\circ}C$ for 5 hrs, but destroyed 30%, 28% and 40% of paeoniflorin by treatment at 10$0^{\circ}C$ for 5 hrs, 115$^{\circ}C$ and 121$^{\circ}C$ for 10 minutes, respectively. The paeoniflorin was continueously extracted for 4 hrs from the dry pieces of peony roots(0.5$\times$0.5$\times$0.5cm) in boiling water but destroyed gradually after 4 hrs at 10$0^{\circ}C$. Paeoniflorins in 70% ethanol extracts of peony root were not destroyed at all in the process of concentration to dry powder at 60"C on vacuum.cuum.

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Lysozyme Activity in Buffalo Milk: Effect of Lactation Period, Parity, Mastitis, Season in India, pH and Milk Processing Heat Treatment

  • Priyadarshini, Subhadra;Kansal, Vinod K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권6호
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    • pp.895-899
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    • 2002
  • Lysozyme activity in buffalo milk in relation to the period of lactation, parity of animal, weather conditions and udder infections was studied. Effect of storage and heat processing of milk on lysozyme activity was determined. Lysozyme activity was higher in buffalo milk than in cow milk. Buffalo colostrum showed lysozyme activity 5 times of that in mature milk. Lysozyme activity in buffalo milk was not influenced by the parity of animal and the stage of lactation, however, it increased during extreme whether conditions (winter and summer). Lysozyme in both cow and buffalo milk exhibited maximum activity at pH 7.4. Buffalo milk lysozyme was fully stable while the cow milk lysozyme was partly inactivated by pasteurization (low temperature-long time as well as high temperature-short time treatments). Lysozyme in buffalo milk was more stable than in cow milk during storage and heat treatment. A 10 to 50-fold increase in milk lysozyme activity was observed in mastitic cows. An assay of lysozyme activity in milk can be used to diagnose mastitis in cattle but not in buffaloes. Some buffaloes exhibited 1000 fold greater lysozyme activity and moderately raised somatic cell count in milk, but there was no sign of mastitis in these animals. A possible role of milk lysozyme in prevention of mastitis in buffaloes is discussed.

Wet preparation of calcium phosphates from aqueous solutions

  • Lee, Byeong Woo;Hong, Il Gok
    • Journal of Ceramic Processing Research
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    • 제20권6호
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    • pp.655-659
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    • 2019
  • Calcium phosphates such as HA (hydroxyapatite), β-TCP (tricalcium phosphate) and biphasic HA/β-TCP, were synthesized by wet chemical precipitation in aqueous solution combined with ball milling process. Nanosize powders of the calcium phosphates were synthesized using Ca(OH)2 and H3PO4. The effects of initial precursor Ca/P ratio (1.30, 1.50 and 1.67), ball milling process and post heat-treatment on the phase evolution behavior of the powders were investigated. The phase of resulting powder was controllable by adjusting the initial Ca/P ratio. HA was the only phase for as-prepared powders in both cases of Ca/P ratios of 1.50 and 1.67. The single HA phase without any noticeable second phase was obtained for the initial Ca/P ratio of 1.67 in the overall heat-treatment range. Pure β-TCP and biphasic calcium phosphate (HA/β-TCP) were synthesized from precursor solutions having Ca/P molar ratios of 1.30 and 1.50, respectively, after having been heat-treated above 700 ℃. The β-TCP phase has appeared on the pre-existing DCPD (dicalcium phosphate dihydrate) and/or HA phase. Dense ceramics having translucency were obtained at a considerably lower sintering temperature. The modified process offered a fast, convenient and economical route for the synthesis of calcium phosphates.

Heat-processed Panax ginseng and diabetic renal damage: active components and action mechanism

  • Kang, Ki Sung;Ham, Jungyeob;Kim, Young-Joo;Park, Jeong Hill;Cho, Eun-Ju;Yamabe, Noriko
    • Journal of Ginseng Research
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    • 제37권4호
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    • pp.379-388
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    • 2013
  • Diabetic nephropathy is one of the serious complications in patients with either type 1 or 2 diabetes mellitus but current treatments remain unsatisfactory. Results of clinical research studies demonstrate that Panax ginseng can help adjust blood pressure and reduce blood sugar and may be advantageous in the treatment of tuberculosis and kidney damage in people with diabetes. The heat-processing method to strengthen the efficacy of P. ginseng has been well-defined based on a long history of ethnopharmacological evidence. The protective effects of P. ginseng on pathological conditions and renal damage associated with diabetic nephropathy in the animal models were markedly improved by heat-processing. The concentrations of less-polar ginsenosides (20(S)-Rg3, 20(R)-Rg3, Rg5, and Rk1) and maltol in P. ginseng were significantly increased in a heat-processing temperature-dependent manner. Based on researches in animal models of diabetes, ginsenoside 20(S)-Rg3 and maltol were evaluated to have therapeutic potential against diabetic renal damage. These effects were achieved through the inhibition of inflammatory pathway activated by oxidative stress and advanced glycation endproducts. These findings indicate that ginsenoside 20(S)-Rg3 and maltol are important bioactive constituents of heat-processed ginseng in the control of pathological conditions associated with diabetic nephropathy.

표면경화에 의한 고강도 알루미늄 합금의 마모 특성에 관한 연구 (A Study on Wear Characteristics of High strength aluminum alloys by Surface Hardening)

  • 이남수;허선철;이광영;박원조
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.1601-1606
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    • 2007
  • In order for high strength aluminum alloys to be used in transportation systems and the aerospace industry, excellent mechanical and physical properties are required. In particular, excellent anti-abrasion property is indispensable for parts that require driving force. In general, surface treatment technologies such as high frequency heat treatment, gas solid carburizing, surface rolling, shot peening are used as ways of improving anti-abrasion property. Among various surface treatment technologies, this research chose shot peening processing for Al7075-T6, which is well known as representative high-strength alloy steel. Wear characteristics were compared and analyzed after shot peening processing with shot ball velocities of 40m/s and 70m/s in order to investigate the effects of shot peening processing on wear characteristics.

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Determination of Quality Changes throughout Process ing Steps in Chinese-style Pork Jerky

  • Chen, W.S.;Liu, D.C.;Chen, M.T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권5호
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    • pp.700-704
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    • 2004
  • Chinese-style pork jerky is a typical intermediate moisture meat product obtained by curing, drying and roasting pork samples. The chemical, physical and microbiological characteristics of pork jerky were evaluated throughout processing. The moisture content varied from 72.5% to 23.4 or 19.6% and aw varied form 0.97 to 0.74 or 0.72 in accordance with processing steps. The pork jerky roasted at $200^{\circ}C$ had higher shear value than roasted at $150^{\circ}C$ because the moisture content and aw of the former sample was lower than the later sample. The nitrite losses during whole processing steps amount to nearly 50%. The TBA value of pork jerky varied from 0.34 to 9.25 or 9.83 mg of malonaldehyde depended on processing steps. The VBN value of pork jerky ranging from 0.25 to 22.4 or 23.5 mg/kg depended upon processing steps. The ATPase activity of myofibrillar proteins during processing steps were partly or entirely denatured by the heat-drying or heat-roasting treatment. A gradual decrease in microorganism count during processing of pork jerky was also observed.

주정처리와 수분-열처리 떡볶이 떡의 저장기간에 따른 품질 특성 (Quality Characteristics of Tteokbokki Tteok after Ethanol and Heat Moisture Treatments During the Storage Periods)

  • 최해연;김진성;고은성;우혜은;박종대;성정민
    • 한국식생활문화학회지
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    • 제36권3호
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    • pp.325-332
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    • 2021
  • This study sought to investigate the effects of heat-moisture treatment (HMT) and ethanol treatment (EOH) for improving the quality and storage stability of Tteokbokki Tteok. The quality characteristics were evaluated by moisture, pH, color, texture profile analysis, and observing the microbial properties after the heat-moisture treatment or ethanol treatment. As the storage period increased, the moisture content of Tteokbokki Tteok tended to decrease except for the HMT group (p<0.05) while the pH did not show significant variation except for the EOH group (p<0.05). While measuring the color, the L-value tended to increase in all groups during the storage period. The a-value and the b-value showed the highest values in the HMT group and the control (CON) group, respectively. In the texture profile analysis, all groups showed a significant tendency to increase levels of hardness and chewiness as the storage period increased (p<0.05). The HMT group showed an increase in hardness and adhesiveness, which are characteristics of the HMT treatment. The results of examining the microbial properties of Tteokbokki Tteok showed that the total microbial count in the HMT group was 4.52 on the 8th day of storage, which was lower than the level in the CON group and the EOH group on the 4th day of storage. Yeast and mold were not measured during the storage period. Thus the results of this study showed that when manufacturing Tteokbokki Tteok, the heat-moisture treatment of rice powder increased the storage stability by delaying microbial growth and also had positive effects on quality.