• Title/Summary/Keyword: heat treatment processing

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

  • LEE Hee Jung;LEE Tae Seek;SON Kwang Tae;BYUN Han Seok;KIM Ji Hoe;PARK Jeong Heum;PARK Mi Jung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.6
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    • pp.524-528
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    • 2000
  • Effect of food additives on the heat sensitivity of listeria monocytogenes H-12 inoculated into Pollack surimi was investigated and also confirmed the effectiveness of various decontamination method such as tap water washing, chlorination, ultraviolet irradiation and heat treatment haying been applied on cooking utensils. Food additives such as polyphosphate, chitosan, and potassium sorbate increased heat sensitivity of t monocytogenes H-12 and polyphosphate showed the strongest synergistic effect. The tested strain was not detected from stainless steel and plastic cutting board contaminated with $10^4{\~}10^5/cm^2$ of L monocytogenes H-12 after tap water washing for 10 seconds or 1 minute, but washing effect was not found in wooden cutting board. The chlorination of stainless steel and plastic cutting board for 10 seconds with $5{\~}50 ppm$ solution eliminated all cells of the contaminated strain, however any change of the viable cell count was not observed in the chlorination of wooden cutting board, W irradiation on stainless steel and plastic cutting board for 5 minutes with 15 W above 30 cm eliminated the contaminated strain, but the tested strain was still found after 60 seconds of irradiation on wooden cutting board. The treatment of hot water on all used cutting boards for 10 seconds at $70^{\circ}C$ resulted in complete loss of viability of the contaminated strain.

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

  • 김태강;김광중
    • Food Science and Preservation
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    • v.4 no.1
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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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Effects of Austenitization and Sn Addition on Processing Window of Austempered Cast-iron (오스템퍼드 구상흑연주철의 Processing Window에 미치는 오스테나이징 조건 및 주석의 영향)

  • Kwon, M.Y.;Baek, S.H.;Yoon, D.K.;Kim, M.J.;Kim, D.J.;Kwon, H.W.;Ko, Y.G.
    • Transactions of Materials Processing
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    • v.30 no.1
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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.

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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    • v.15 no.6
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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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    • v.20 no.6
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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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    • v.37 no.4
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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.

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

  • Lee, Nam-Soo;Huh, Sun-Chul;Lee, Kwang-Young;Park, Won-Jo
    • Proceedings of the KSME Conference
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    • 2007.05a
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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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Quality Characteristics of Tteokbokki Tteok after Ethanol and Heat Moisture Treatments During the Storage Periods (주정처리와 수분-열처리 떡볶이 떡의 저장기간에 따른 품질 특성)

  • Choi, Hae-Yeon;Kim, Jin-Seong;Go, Eun-Seong;Woo, Hye-Eun;Park, Jong-Dae;Sung, Jung-Min
    • Journal of the Korean Society of Food Culture
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    • v.36 no.3
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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.

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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    • v.17 no.5
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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.