• 제목/요약/키워드: discoloration

검색결과 792건 처리시간 0.032초

굴 통조림의 변색과 그 방지 (DISCOLORATION OF CANNED BOILED OYSTER)

  • 이강호;최위경;변재형;김무남
    • 한국수산과학회지
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    • 제9권2호
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    • pp.111-119
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    • 1976
  • Discoloration of canned boiled oyster namely greening, yellowing and browning often occur separately or associatively in the storage of the product. Greening is mainly caused by the appearance of chlorophyll and its derivatives on the surface around the digestive diverticula of the oyster and yellowing by dispersion of carotenoid. Browning reactions by sugar amino condensation or enzymatic action, tyrosinase, also cause an undesirable color development. In this paper, the stability and the changes in distributional or partitional ratio of chlorophyll and carotenoid pigment of meat vs viscera in raw and canned oyster during six month storage in order to measure the dispersion rate of both pigments between meat and viscera, and to evaluate the feasibility of discoloration of oyster meat. The development of brownish pigment and the toss of free tyrosine in oyster were also determined to compare the readiness of color development. In addition the influence of processing and storage conditions to the dispersion rate and the tendency of discoloration, and finally the effect of inhibitor were discussed. The results showed that greening or yellowing was initiated by the dispersion of chlorophyll or carotenoids from viscera to the meat of oyster, and the dispersion rate of carotenoid was much higher than the chlorophyll's, so that, yellowing appeared a leading reaction of discoloration. The dispersion rate was obviously fastened by raising the temperature in the process of sterilization and storage. Consequently, the low temperature storage could largely retard the occurance of yellowing or greening of oyster meat. The pH control of canned oyster did not seem to affect the dispersion of pigment but significantly did on the stability of the piqments. Browning by the reaction of sugar-amino condensation and enzymatic oxidation of tyrosine was positively detected in canned oyster meat. The development of brownish color was influenced rather by the storage temperature than the heating process. Addition of sodium sulfite in can or treating the boiled oyster with sulfite solution prior to filling seemed possibly inhibit the color development particularly in cold-storaged oyster meat.

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병해충과 변색미(變色米) 발생(發生)과의 관계(關係)에 관한 연구(硏究) (Insects and Pathogens Associated with Rice Grain Discoloration and Their Relationship in the Philippines)

  • 이승찬;M.E. 알멘다;J.M. 본만;E.A. 하인리크
    • 한국응용곤충학회지
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    • 제25권2호
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    • pp.107-112
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    • 1986
  • 변색미(變色米) 발생(發生)에 관여(關與)하는 병원균(病原菌)과 해충을 분류동정(分類同定)한 결과(結果) 해충으로는 허리노린재과(科)에 속하는 Leptocorisa oratorius가 우점종(優占種)이었고 노린재과(科)인 Menida varipennis. Stollia ventralis 및 Nezara viridula 등이 관여(關與)하였으며 병원균(病原菌)으로는 Drechslera oryzae. Curvularia lunata, Trichoniella padwickii, Sarocladium oryzae, Alternaria tenuis 및 Fusarium solani 등이 관여(關與)하였다. 병원균(病原菌)과 해충의 복합발생시(複合發生時)에 변색미발생(變色米發生)이 더 심하였고 병원균(病原菌)만의 발생시(發生時)는 변색미(變色米) 발생(發生)에 주로 영향(影響)을 미쳤으며 노린재류만의 발생시(發生時)는 수량감수(收量減收)에 더 큰 영향(影響)을 주었다. 그리고 노린재류에 의한 벼 유숙기간(乳熟期間)의 흡즙(吸汁)은 병원균침입(病原菌侵入)을 조장(助長)하여 벼의 질적(質的) 변화(變化)와 양적(量的) 감소(滅少)에 크게 영향(影響)하였다.

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Stain Fungi and Discoloration Control on Rubberwood (Hevea brasiliensis Muell. Arg.) by Vacuum-Pressure Treatment with Catechin from Gambir (Uncaria gambir Roxb.)

  • Dodi NANDIKA;Elis Nina HERLIYANA;Arinana ARINANA;Yusuf Sudo HADI;Mohamad Miftah RAHMAN
    • Journal of the Korean Wood Science and Technology
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    • 제51권3호
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    • pp.183-196
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    • 2023
  • Recently, the morphological and molecular features of five stain fungi infecting rubberwood (Hevea brasiliensis), namely Paecilomyces maximus, Paecilomyces formosus, Penicillium crustosum, Paecilomyces lecythidis and Aspergillus chevalieri, have been studied. Prior to this study, the authors revealed that catechin from gambir (Uncaria gambir) could inhibit the growth of the white-rot fungus Schizophyllum commune, and it was important to determine the bioactivity of the aforementioned agent against A. chevalieri. The efficacy of the biocidal agent was examined using a laboratory wooden block test. Rubberwood blocks, 8 mm in thickness, 20 mm in width, and 30 mm in length, were impregnated with catechin solution at concentrations of 6%, 9%, 12%, and 15% (w/v) using the vacuum-pressure method, and their bioactivity was monitored over three weeks through visual and scanning electron microscope assessment of fungal growth as well as the discoloration intensity of the wood samples. The results showed that catechin treatment increased the resistance of wood samples to A. chevalieri. Overall, the higher the catechin concentration, the lower the fungal growth. The lowest fungal growth was observed in the wood samples treated with 12% and 15% catechin (score of 0), demonstrating no discoloration. In contrast, the fungal growth score of the untreated wood samples reached 4, indicating severe discoloration. Catechins appear to be adequate biofungicides against stain fungi in rubberwood.

전치부 전부도재관을 이용한 테트라싸이클린 착색의 심미보철 회복 증례 (IPS e.max CAD 블록의 이용) (Esthetic Rehabilitation of Anterior Dentition by All Ceramic Crowns Using IPS e.max CAD : A Case of Tetracycline Discoloration)

  • 김재홍;조영규;김혜영
    • 치위생과학회지
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    • 제11권4호
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    • pp.299-303
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    • 2011
  • The purpose of this case report was to present an example of an esthetic and functional rehabilitation of anterior teeth with tetracycline discoloration and minor morphological abnormality of a 39-year old female. A chairside computer-aided design/computer-aided manufacturing (CAD/CAM) system with CEREC AC was applied for the prosthetic procedure and all ceramic crowns made with lithum disilicate (IPS e.max CAD) restored the esthetic and functional features of sixteen anterior teeth successfully.

연작지 토양에서 토양연증제 처리가 인삼의 근부, 적변 및 생육에 미치는 영향 (Effect of Soil Fumigation on Growth, Root Rot, and Red Discoloration of Panax ginseng in Replanted Soils)

  • 안용준;김홍진
    • Journal of Ginseng Research
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    • 제6권1호
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    • pp.46-55
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    • 1982
  • The effect of soil fumigation on the growth, yield, root-rot and red discoloration of 2 year-old ginseng, Panax ginseng C. A. Meyer was investigated in the ginseng replanted fie14 Six soil fumigants, Cylone, Basamid, D-D, Dowfume MC-2, Telone C-17, and Vapam were applied in March, 1980, and 2 year-old ginseng plants were transplanted in April, 1981, and sampled in August, 1981. Growth an yields in Cylone and Basamid treated plots in the replanted soil were better than those in control. Especially, growth and yields of ginseng in Cyclone treated Plots were comparable to these in untreated virgin soil. Control effect of soil fumigants used on root-rot was in the order of Cylone, Basamid, Telone C-17, and the lest of them showed neglect fur effect. Frequency of red discoloration was 8% in Cyclone treated plots, 9% in Basamid treated plots 83.3% in the untreated ginseng replanted soil, and 2.5% in the untreated virgin soil.

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Furfurylation Effects on Discoloration and Physical-Mechanical Properties of Wood from Tropical Plantation Forests

  • HADI, Yusuf Sudo;HERLIYANA, Elis Nina;PARI, Gustan;PARI, Rohmah;ABDILLAH, Imam Busyra
    • Journal of the Korean Wood Science and Technology
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    • 제50권1호
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    • pp.46-58
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    • 2022
  • Wood from tropical plantation forests has lower physical and mechanical properties than mature wood. Furfuryl alcohol (FA) impregnation into the wood could help to enhance hydrophobic properties, dimensional stability, and structural strength. Furfurylation was applied to specimens of the following four fast-growing tropical wood species: jabon (Anthocephalus cadamba), sengon (Falcataria moluccana), mangium (Acacia mangium), and pine (Pinus merkusii). The discoloration and physical and mechanical properties were subsequently measured, and the results showed that furfurylated wood had a darker color and better physical and mechanical properties than untreated wood. Specifically, the furfurylated wood had higher density, modulus of elasticity, and hardness and lower moisture content, water absorption, swelling, and shrinkage. The furfurylation significantly enhanced physical and mechanical properties.

저온에 의한 수도의 Discoloration 발생에 관한 연구-온도에 의한 가용성단백질구성 변화에 관하여- (Studies on the leaf discoloration caused by low temperature-Change of soluble protein components by temperature -)

  • 박경배;전중효행;원전이랑
    • 한국작물학회지
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    • 제23권1호
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    • pp.1-4
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    • 1978
  • 단백질구성 변화를 여러가지 온도조건에서 Japonica형인 진흥, Indica$\times$Japonica교잡품종인 통일, 밀양 2003, 영남조생, 유신등을 공시하여 'Growth Cabinet'를 사용하여 검토 하였던바 다음과 같은 결과를 얻었다. 1. 저온하에서 엽록소함양감소는 Japonica형 품종보다 Indica형 품종에서 심하였다. 2. 단백질구성비(저분자가용성단백질에 대한 고분자가용성단백질의 비)는 고온하에서 높았고, 저온하에서 낮았다. 3. 품종간 단백질구성비는 저온하에서 Japonica형 품종보다 Indica형 품종이 낮았다. 4. 엽신의 엽록소함양과 가용성단백질구성비와는 정의 유의 상관관계가 인정되었다.관계가 인정되었다.

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원주 법천사지 지광국사탑의 표면오염 및 성인 해석 (Interpretation of Surface Contamination and Genesis on the Stupa of the State Preceptor Jigwang from the Beopcheonsaji Temple Site in Wonju, Korea)

  • 강산하;이주목;이규혜;김사덕;이찬희
    • 보존과학회지
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    • 제34권3호
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    • pp.211-225
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    • 2018
  • 원주 법천사지 지광국사탑(국보 제101호)은 고려시대(11세기 경)에 조성된, 양식과 기법이 매우 뛰어난 승탑이다. 1912년에 일본 오사카로 무단 반출되었다가 반환되었으며, 한국전쟁기간에 큰 손상을 입었다. 이후 모르타르와 같은 재료를 사용하여 보수되었으며, 이 과정에서 국립고궁박물관 옆으로 이건되었다. 지광국사탑의 표면오염은 대부분 보수재료를 중심으로 나타난다. 변색 등급이 높은 흑화는 북측면과 앙시에서 비교적 높은 점유율을 보였다. 이는 상대적인 수분유지시간에 따른 것으로 해석된다. 표면오염물은 대부분 방해석과 석고이며, 특히 흑화부위는 2차적으로 대기오염물질의 영향을 받았다. 상대적으로 변색도가 낮은 석재에서도 조암광물사이에서 염결정이 확인되며 부분적으로 표면을 피복하고 있다. 지광국사탑은 보수과정에서 사용된 모르타르가 열화되면서 용해된 석회물질의 영향으로 탑신 전반에 걸쳐 변색에 의한 손상이 넓게 나타난 것으로 해석된다. 따라서 보존처리 과정에서 표면오염물 제거와 세정 및 탈염처리를 통해 염에 의한 물리화학적 손상을 제어할 필요가 있다.

발효음식이 의치상레진의 색상 및 표면경도 변화에 미치는 영향 (THE EFFECT OF FERMENTED FOODS ON THE COLOR AND HARDNESS CHANGE OF DENTURE BASE ACRYLIC RESINS)

  • 전열매;임헌송;신수연
    • 대한치과보철학회지
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    • 제42권4호
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    • pp.344-355
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    • 2004
  • Statement of problem: For a long time, many of denture base acrylic resins have been used for edentulous and partial edentulous patients because of easy manipulation and good mechanical properties, but its esthetic aspect has not been commented enough. Denture base acrylic resins also has caused esthetic problems due to discoloration or staining as in esthetic restoration. Many researches and reports have treated the problems and accomplished esthetic improvement. But these researches and reports dealt with general food colors or beverages, not with fermented foods. Purpose: This study is designed to assess what fermented foods, such as soy sauce, gochujang, and toenjang that many of Koreans have taken in, influence on the color and hardness variation of denture base acrylic resins. Materials and methods: For the procedure, twelve disks per 4 denture base acrylic resins were fabricated with a thickness of 2mm and 16mm in diameter. Each seven specimen were measured for discoloration with spectrophotometer, while the others, five specimen, for surface hardness change with Barcol hardness tester, over time. Each 12 specimen were immersed into the 4 beakers of fermented foods(soy sauces, gochujangs, toenjangs, deionized water), and $L^{*},a^{*}$, and $b^*$ values were measured for the color difference$({\Delta}E^*)$, on the 1st, 7th, and 28th day with spectrophotometer, with the measurement of surface hardness change. Each data observed was processed statistically. Results: The findings are as follows; Discoloration 1. All of denture base resins was not influenced by the kind of fermented foods, except for $QC20^{(R)}$ 2. Soy sauce and red pepper paste caused more change for denture base resins than deionized water and soy bean paste, except for Perform$^{(R)}$ 3. Most significant change was shown in Lucitone 199$^{(R)}$, whereas Perform$^{(R)}$ results in the least change for all immersed solution, with no statistical significance. Hardness change 1. Barcol hardness values in deposited specimens have been changed low degree, but with significant statistical change according to the kind of food and duration. 2. Lucitone$^{(R)}$ 199 as significantly lower Barcol hardness value than others do. Conclusion: Based on the above results, it suggests that the habitual intake of fermented foods is not helpful for the color stability of denture base acrylic resins because Soy sauce and red pepper paste mainly caused discoloration and surface hardness change. Particularly $Lucitone199^{(R)}$ shows specific discoloration and low surface hardness values. Therefore, it is recommended giving caution patients with denture of $Lucitone199^{(R)}$ especially against the habitual intake of fermented foods like soy sauce and red pepper paste.

일본 히로시마현 마애화령석지장(磨崖和靈石地藏)의 해수 침수에 의한 풍화특성 (Weathering Characteristics according to Seawater Immersion of the Magai Wareiishi Jizo (Buddhist Statue Carved on Rock Surface) in Hiroshima, Japan)

  • 이선명;이명성;전유근;이재만
    • 보존과학회지
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    • 제28권4호
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    • pp.329-341
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    • 2012
  • 마애화령석지장은 해안가에 인접해 있고 해수에 의해 주기적으로 일정 부분이 침수되는 특수한 입지적 조건에 있다. 마애불을 구성하는 암석은 중립질 또는 조립질을 띠는 흑운모화강암으로 내구성이 강한 편이나, 암석 내부에 침투한 염용액과 주변 환경과의 복잡한 상호작용에 의해 구성암석의 색과 강도 및 내구성 등 물성이 변화된 상태이다. 마애불을 이루는 암석은 염(NaCl)결정화 작용에 의한 표면층 박리박락이 심각하다. 박리박락(14.6%)은 해수의 주요 경계면을 중심으로 대기에 상시 노출되는 상부에 집중되어 있다. 반면, 해수에 의해 주기적으로 침수되는 암괴 하부는 오염물이 침착되어 흑화층을 나타내며 이와 함께 갈색변색과 생물오염이 중첩된 상태이다. 표면 오염 및 변질은 흑색 변색(29.2%), 황색 변색(14.1%), 갈색 변색(4.4%), 녹색 변색(2.9%)의 순으로 높은 훼손율(50.5%)을 나타냈다. 또한 해수면을 경계로 상부가 해수에 침수되는 하부보다 초음파 속도가 낮고 편차가 커 많은 물성 변화가 있었음을 알 수 있으며, 특히 해수 침투 경계면의 표면 물성이 취약함을 확인하였다.