• 제목/요약/키워드: Autoclaving

검색결과 182건 처리시간 0.031초

퇴비화 과정중 전처리방법에 따른 중금속함량의 변화 (Effect of Pre-treatment Methods on Heavy Metals Analysis of organic Solid Wastes during Composting)

  • 박준석;안병구;하은아
    • 유기물자원화
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    • 제10권2호
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    • pp.117-124
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    • 2002
  • 본 연구는 퇴비화 과정 중 일어나는 중금속의 변화를 살펴보고 시료 전처리 방법이 중금속 농도에 미치는 영향을 평가하고자 실시하였다. 전처리 방법으로는 건식, $HNO_3-HClO_4$, aqua-regia, 염산환류, $HNO_3-HClO_4-HF$, 습식가압 분해방법을 시용하였으며, 습식가압 분해방법에서는 각각 $HNO_3$, HCl, $HNO_3(2+1)$의 세 가지 산을 시용하였다. 표준물질 SRM 2781에 대한 시험결과 Cr과 Zn의 회수율은 50-60% 정도로 낮았고, Ni은 100% 이상으로 가장 높았으며, Cd과 Cu는 80-90% 수준이었으며, 건식분해 방법은 회수율이 가장 낮았다. 퇴비원료 물질에 대한 시험에서 습식가압 분해방법은 다른 방법보다 3-4배 이상 높은 Cd농도가 검출되었으며, 건식분해 방법의 회수율은 전반적으로 가장 낮은 회수율을 나타내었다. 퇴비화 기간동안 Cd은 습식가압분해 방법에서 가장 높은 농도가 검출되었다. Cr은 건식분해방법에서 Cu는 aqua-regia분해와 염산환류분해에서 가장 낮게 검출되었다. Pb과 Zn은 중금속 항목중에서 분해방법간 차이가 적었다. Ni은 건식분해에서 다른 방법에 비하여 약 2-6배정도까지 낮게 검출되었다.

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대구지역 치과 의료기관 종사자의 B형간염 예방접종 및 감염관리 실태 (Investigation about the Actual Prevention of Infection and Vaccination against B-type Hepatitis among Dental Workers in Daegu)

  • 은정화;배지영
    • 한국치위생학회지
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    • 제5권2호
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    • pp.219-233
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    • 2005
  • This study was conducted on 185 workers at 73 dental clinics and university hospitals in Daegu to investigate the actual prevention of infection and vaccination against B-type hepatitis among dental workers. 1. According to the result of medical examination, only 35 out of 144 (24%) dental clinic workers had periodic health examination while 7 out of 9 (78%) university hospital workers did. 2. In a survey on vaccination against B-type hepatitis, 52 workers aged 29 or younger (96.3%), 38 dental hygienists (51.9%) and 44 dental workers at dental clinics (81.5%) have not had any vaccination against B-type hepatitis. The rest appeared to have had vaccination or be aware that they had antibody against B-type hepatitis without having to have any vaccination. 3. According to the result of a survey on the existence of antibody by job, 42 (56%) of dental hygienists, 15 (20%) of assistant nurses, 12 (16%) of medical assistants and 6 (8%) of dental technicians did not know whether or not they had antibody. This suggests that all types of dental workers except dental hygienists have low awareness of whether or not they have antibody. 4. In a survey on the relation between general characteristics of subjects and the sterilization of dental equipment, alcohol disinfection of high speed handpiece and low speed handpiece was most common among dental workers aged 29 or younger, and all of those aged over 40 used autoclave. By position, alcohol disinfection was used most commonly for high-speed handpiece. antiseptic solution deposition for disposable suction lips, and autoclaving for impression. By workplace, dental workers at university hospitals used autoc1aving most frequently for high/low speed handpiece while those at dental hospitals and dental clinics used alcohol disinfection most frequently and even some respondents replied that they did not disinfect. For metal cups, workers at dental clinics and dental hospitals did not use any sterilizing method while those at university hospitals used autoclaving. For disposable suction tips, workers at dental clinics used antiseptic solution deposition and those at dental hospitals used alcohol disinfection but some respondents replied that they did not disinfect. For metal suctions and impression trays, autoclaving was most common in all workplaces but some dental clinics replied that they did not disinfect impression trays. According to work experience, alcohol disinfection was most common for high/low speed handpiece. For disposable suction tips, dental workers with 3 years' or shorter work experience, those with 3~6 years' experience and those with 9~12 years' experience used antiseptic solution deposition most commonly, and many of those with 6~9 years replied that they did not disinfect. The results of this study stated above suggest that systematic education is necessary for all dental workers for enhancing th eir awareness of B-type hepatitis and the prevention of infection. Moreover, dental workers are required to make efforts to prevent infection with B-type hepatitis voluntarily and actively.

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고온가압 처리에 의한 식용색소의 화학안정성 및 산화방지활성 변화 (Changes in color stability and antioxidant properties of dietary pigments after thermal processing at high pressures)

  • 오보은;김건희;홍정일
    • 한국식품과학회지
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    • 제54권3호
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    • pp.257-263
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    • 2022
  • 본 연구에서는 총 34종의 천연 및 합성 식용색소류에 대하여 식품 가공에서 일반적인 멸균처리 방법인 고온가압 처리(121℃, 15 psi, 15 min)를 실시하고, 이들의 색 안정성 및 산화방지활성의 변화를 조사하였다. 고온가압 처리 후 19종의 색소가 10% 이하의 peak 흡광도 감소를 나타내어 비교적 안정하였으나, 올레오레진 심황, 포도과립, 수용성 β-카로텐, 수용성 파프리카, 및 비트레드 등 5종의 색소는 잔류 색도 60% 이하로 불안정 하였고, 특히 수용성 파프리카와 비트레드는 10% 정도의 잔류 색도를 나타내어 매우 불안정했다. 각 색소들의 탈색 및 색도 변화와 이들의 산화방지활성의 변화는 일관된 결과를 나타내지 않았으나 비트레드와 파프리카 색소류 들은 색도의 감소와 함께 현저한 산화방지 활성의 감소가 함께 나타났으며, 올레오레진 심황은 50% 이상의 탈색에도 불구하고 산화방지활성이 유의적으로 증가하는 결과를 보였다. 본 연구결과는 식품의 가공이나 조리 중에 첨가되는 식용 색소류의 색 안정성과 산화방지 활성이 고온가압 처리에 의해 크게 영향을 받으나, 색소 탈색 정도와 산화방지활성의 변화에 밀접한 상관 관계가 나타나지 않음을 시사한다.

Influence of Amylose Content on Formation and Characteristics of Enzyme-resistant Starch

  • Yoon, Ji-Young;Lee, Young-Eun
    • Preventive Nutrition and Food Science
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    • 제3권4호
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    • pp.303-308
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    • 1998
  • Influence of amylose content on formation and characteristics of enzyme-resistant starch (RS) was investigated by scanning electron microscopy, X-ray diffractometry and differential scanning calorimetry. RS yield increased up to 36.1 % as the amylose content of corn starch increased. Starch granules of Amyulomaize V and Ⅶ were more rounded and smaller than those of regular corn ; some were elongated and had appendages. After autoclaving -cooling cycles, the granular structure disappeared and a continous spongy-like porous network was visible in regular corn starch ; the granular structure was stillevident in parts in Amylomaize V and Ⅶ starches. In all isolated RS residues , the porous structures were no longer visible and more compact formations predominated. While regular corn starch showed an A-type X-ray profile, Amylomaize V and Ⅶ starches exhibited a combination of B- and V-types. Regular corn starch lost most of its crystallinity during autoclaving , but the crystallinity was still left in Amylomaize starches as diffuse or poor B-types. All RS residues showed the presence of poor B-type regardless of amylose contents. Transition temperatures and enthalypy of native starches were a little higher in Amylomaize V and Ⅶ starches than those of regular corn starch . Regardless of amylose contents, all RS residues exhibited an endothermic transition over a similar temperature range (135 $^{\circ}C$~169$^{\circ}C$), with a mean peak temperature of ~154$^{\circ}C$, which is generally foud for retrograded amylose crystallities. Higher transition temperature, enthalypy, and RS yield of AMylomaize V and Ⅶ starches were related granular stability shown by the microscopic and crystallographic studies.

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${\alpha}$화 보리쌀의 제조에 관한 연구 -제 1 보 : ${\alpha}$화 보리쌀의 수율과 호화도- (Studies on the Preparation of Polished ${\alpha}-Barley$ -I. The Yield and Degree of Gelatinization-)

  • 김형수;강옥주;류은순
    • 한국식품과학회지
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    • 제15권2호
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    • pp.155-159
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    • 1983
  • 겉보리 품종 중 부농, 쌀보리 품종 중 세도하다가를 각각 50%와 65%, 60%와 75%로 도정수율을 달리하고, 수침, 가열, 건조하여 ${\alpha}$화 보리쌀을 제조하였다. 각 시료의 일반성분을 분석하고, 여러 가지 열처리 조건을 달리하여 가열 건조한 보리쌀의 수율 및 호화도를 측정한 결과는 다음과 같다. 1. ${\alpha}$화 보리쌀의 수율은 microwave oven가열, 생증기처리, 가압솥처리시 $95{\sim}98%$이며 열탕처리의 경우는 $74{\sim}89%$로서 낮았다. 2. ${\alpha}$화 보리쌀의 호화도는 microwave oven 1분 가열로서 $31{\sim}42%$, microwave oven에서 5분, 생증기처리 10분과 20분에서 90% 내외를 보였고, 생증기처리 30분, 열탕처리, 가압솥처리에서 95%이상의 호화도를 보였다.

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아밀로오스 함량이 다른 옥수수 전분의 겔 형성과 특성 (Formation and Properties of Gel from Maize Starches with Different Amylose Content)

  • 문세훈;김완수;신말식
    • 한국식품조리과학회지
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    • 제13권4호
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    • pp.379-383
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    • 1997
  • 아밀로오스 함량이 다른 옥수수 전분을 121$^{\circ}C$에서 호화시켜 팽윤력과 용해도를 측정했을때, 팽윤력은 찰옥수수 전분인 Amioca가 가장 컸고, PFP, Amaizo, Amylomaize VII 순이었으며 Amaizo의 경우 용출된 겉보기 아밀로오스의 요드 친화력이 가장 높았고, 용해도 역시 높게 나타났다. BrooHield viscometer를 이용하여 0.25 N NaOH 용액으로 측정한 알칼리 호화양상은 Amylomaize VII이 최고점도 l0$\times$$10^3$cp를 나타낸 반면 Amaizo는 70$\times$$10^3$cp로 Amylomaize VII에 비해 높은 값을 나타냈고, PFP는 70$\times$$10^3$cp까지 증가했다가 감소하였다. 전분과 물을 1 : 9로 하여 121$^{\circ}C$에서 가열-냉각 횟수를 4회 반복하며, 각 단계에서 형성된 겔의 성질을 비교하면 Amaizo로 만든 겔의 견고성, 부착성, 탄성과 응집성이 가장 컸으며, 견고성은 가열-냉각처리를 2회 반복한 경우 가장 컸고 그 후 감소하였다. 옥수수전분 겔의 성질은 아밀로오스 함량보다는 사슬길이나 가열 중 용출되는 부분의 성질에 더 상관성이 높았다.

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Pectin from Passion Fruit Fiber and Its Modification by Pectinmethylesterase

  • Contreras-Esquivel, Juan Carlos;Aguilar, Cristobal N.;Montanez, Julio C.;Brandelli, Adriano;Espinoza-Perez, Judith D.;Renard, Catherine M.G.C.
    • Preventive Nutrition and Food Science
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    • 제15권1호
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    • pp.57-66
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    • 2010
  • Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at $121^{\circ}C$. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 mg/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.

대파 향미유의 원재료 부위별 향미특성 (Flavor Characteristics according to Parts of Raw Materials on Allium fistulosum L. Seasoning Oil)

  • 구본순
    • 한국식품저장유통학회지
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    • 제12권5호
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    • pp.465-469
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    • 2005
  • 대파를 부위별로 분획하여 대파 전체, 잎, 줄기, 뿌리를 동량 처리하여 각각 autoclaving법에 의하여 대두유를 기질로 WOSO를 제조하였다. 이들 4종 WOSO의 이화학적 특성은 큰 차이가 없었으며, 대파 잎향미유의 경우 Lovibond 색상에서 고유의 청색을 상대적으로 강하게 나타내는 특성을 나타내었다. 휘발성 향기성분은 총 35종이 검출되었으며, 주요 향기성분은 methyl propenyl trisulfide와 propenyl propyl trisulfide이었으며, 각각 대파 뿌리향미유에서 가장 높은 26.94 ppm, 26.26 ppm으로 나타났다. 이와 함께 propenyl propyl disulfide 등이 WOSO의 향미특성에 큰 영향을 미치는 성분인 것으로 판단된다. 또한, carbonyl 화합물 함량은 각각 79.46 ${\mu}g$, 77.17 ${\mu}g$, 76.32 ${\mu}g$, 73. 62 ${\mu}g$이었다. 결론적으로 WOSO에서 고유의 구수한 향미를 나타내는 부위는 잎이나 줄기가 아니라 뿌리 부분임을 확인할 수 있었다.

멥쌀전분으로 제조한 RS3형 저항전분이 인절미의 특성에 미치는 영향 (Effect of RS3 type resistant starch prepared from nonwaxy rice starch on the properties of Injulmi)

  • 김정옥;신말식
    • 한국식품조리과학회지
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    • 제19권1호
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    • pp.65-71
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    • 2003
  • 멥쌀전분, 찹쌀가루, 멥쌀전분으로 제조한 RS3형 저항전분의 수분 함량은 비슷하였으나, 단백질 함량, 회분 함량, 지방질 한량은 찹쌀가루가 가장 높았다. 멥쌀전분으로 제조한 RS3형 저항전분의 RS함량은 9.10% 이었다. 멥쌀전분으로 제조한 RS3형 저항전분을 첨가한 인절미 경도와 부착성을 레오메타로 측정하였을 때 저장기간과 RS3형 저항전분의 첨가량이 증가할수록 증가하였다. 관능검사 결과, RS3형 저항전분을 첨가한 인절미의 경도가 무첨가 인절미보다 높은 값을 보였으나, 탄성, 부착성, 부드러움성, 전체적인 품질은 RS3형 저항전분의 첨가량에 따라 유의적인 차이를 보이지 않았으며, 전체적인 품질은 경도와 음의 상관관계를 보였다(r=-0.331, p<0.05).

調味用 油狀 Sauce類의 開發에 관한 硏究(1) (Development of Availability for Oil Base Spiced Sauces (1))

  • 안명수;구본순
    • 한국식품조리과학회지
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    • 제8권2호
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    • pp.95-105
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    • 1992
  • This study was carried on the Seasoning Oil production by Autoclaving Method in order to research a developed method. The Raw, Extract states of seasoning vegetables-Garlic, Onion and Ginger were added 40, 60% (w/w) of total amounts to corn salad oil. All samples treated with various conditions were determined physicochemical characteristics by Acid value, Peroxide value, Iodine value, Refractive Index, and Volatile Carbonyl Compound Content during incubating $(40{\pm}2^{\circ}C)$ and heating $(185{\pm}2^{\circ}C)$. The results were obtained as follws; 1. During incubation at $40{\pm}2^{\circ}C$, the order of antioxidative effects among seasoning vegetables was Ginger>Garlic>BHA>Onion and Extract state were more effective man Raw state. also the antioxidative effects of the seasoning vegetables were increased proportionally with the concentration in the Seasoning Oils. 2. In the case of heat treatment $(185{\pm}2^{\circ}C)$, AV, POV, IV and RI of each Seasoning Oil were changed very sharply. The antioxidative effect and Carbonyl Compound Content according to heat treatment differed from the type and concentration of seasoning vegetables in oil. Ginger had the most excellent antioxidative effect among seasoning vegetables, and m any case, the adding states of seasoning vegetables into oils were more effective in Extract man Raw states. 3. According to those results, each Seasoning Oil made from Garlic, Onion, Ginger was shown to have antioxidative properties specially in Ginger-Extract-Seasoning Oil. also the Autoclaving Method was thought to be rational method in preparation of Seasoning Oil.

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