• Title/Summary/Keyword: stability period

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Chemical Components of Korean Figs and Its Storage Stability (한국산(韓國産) 무화과(無花果)의 화학조성(化學組城) 및 저장성(貯藏性)에 관(關)하여)

  • Kim, Kil-Hwan
    • Korean Journal of Food Science and Technology
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    • v.13 no.2
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    • pp.165-169
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    • 1981
  • In order to obtain the basic data for processing adaptability of Korean figs, chemical analysis was carried out with 7 cultivar produced at Namhae and 3 cultivar transplanted from abroad. To prolong the storage period, Masan No.1 was packed with PE films with different thickness and stored at $2{\pm}0.5^{wcirc}C$. The results obtained were as follows; 1. Total sugar content, total acidity and pectin were $37{\sim}89.6%$(dry basis), $0.57{\sim}1.08%$, $4.30{\sim}7.79%$, respectively. 2. Changes in moisture content of control during storage were rapid. After 16 days it was decreased about 5% but in the lot packed with PE films. moisture content was slowly decreased. 3. Total sugar and acidity of the figs in the lot packed with 0.08 mm PE film were very slowly decreased but control was not. 4. Changes in hardness, fracturability during storage showed similar decreasing pattern but adhesiveness was increased.

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Effect of Freeze Storage Temperature on the Storage Stability of Frozen Mandu (동결저장온도가 냉동만두의 저장성에 미치는 영향)

  • Jeong, Jin-Woong;Jo, Jin-Ho;Kim, Young-Dong;Kwon, Dong-Jin;Kim, Young-Soo
    • Korean Journal of Food Science and Technology
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    • v.23 no.5
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    • pp.527-531
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    • 1991
  • Frozen mandu, which is one of the main frozen prepared foods, purchased from a local manufacturer, were stored at five constant temperatures ($0,\;-5,\;-10,\;-20\;and\;-30^{\circ}C$) for six months. Effects of the storage temperature and the storage period on the changes in pH, acid value, peroxide value, volatile basic nitrogen, color, sensory score and microbial counts of frozen mandu were studied. The changes in microbiological and physicochemical characteristics were significantly increased in comparison with the initial value after 1 month at $0^{\circ}C$, after 3 months at $-5^{\circ}C$ and after 5 months at $-10^{\circ}C$, but nearly constant in spite of storage periods when the temperature dropped below $-10^{\circ}C$Out of five chemical components, AV and POV were the most reliable components in the quality judgement of frozen mandu and its upper limiting content were 2.56 and 19.35 meq/kg each. Regression equation for shelf life prediction of frozen mandu with sensory scores and POV was determined.

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Improvement on Storage Stability of Soybean Curd using Cuttle Bone Powder Treated with Acetic Acid (유기산처리 갑오징어갑을 이용한 두부의 저장성 개선)

  • Kim, Jin-Soo;Cho, Moon-Lae;Heu, Min-Soo
    • Applied Biological Chemistry
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    • v.46 no.3
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    • pp.183-188
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    • 2003
  • Storage stabilities of soybean curds using cuttle bone powder treated with acetic acid (ATC-soybean curd) and calcium chloride (calcium chloride-soybean curd) as a coagulants were examined. The pH, turbidity of soaking solution, titratable acidity, and viable cell counts of calcium chloride-soybean curd did not change up to 6 days of storage, then decreased rapidly in pH and turbidity and increased rapidly in titratable acidity and viable cell counts, whereas those of ATC-soybean curd did not change up to 9 days of storage, then decreased slowly in pH and turbidity and increased slowly in titratable acidity and viable cell counts. Regardless of coagulants and storage period, white index of soybean curds did not change during cold storage. Hardness and brittleness of calcium chloride-soybean curd decreased rapidly up to 3 days in of storage, remained stable from 3 days to 6 days, then decreased rapidly. Hardness and brittleness of ATC-soybean curd also decreased rapidly up to 3 days in of storage and remained stable from 3 to 9 days, but then decreased slowly. Regardless of coagulants, results of sensory evaluation were similar to those of physicochemical tests. Judging from the above results, shelf-lives were determined as 9 and 6 days for ATC- and calcium chloride-soybean curds, respectively.

Expression of a $\beta$-1,3-Glucanase Gene from Bacillus circulans in B. subtilis and B. megaterium (Bacillus subtilis와 Bacillus megaterium에서의 $\beta$-1,3-glucanase 유전자의 발현)

  • 김기훈;김지연;김한복;이동석
    • Korean Journal of Microbiology
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    • v.37 no.4
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    • pp.253-258
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    • 2001
  • A Bacillus circulans KCTC3004 $\beta$-1,3-glucanase gene contained in a recombinant plasmid pLM460 derived from subcloning the original recombinant plasmid pLM530 was trasferred into a new shuttle vector plasmid pLMS1180 by ligating linearized DNAs of pLM460 and pUB110. B. subtilis RM125 and B. megaterium ATCC14945 transformed with pLMS1180 produced the $\beta$-1,3-glucanase substantially. Most of the enzyme was produced during the exponential growth period. The maxium activities of the $\beta$-1,3-glucanase produced by the Bacillus transformants were compared with that of the B. circulans gene donor strain. The B. subtilis RM125 (pLM1180) enzyme showed the activity 14 times higher than that of the gene donor cells, followed by the B. megaterium ATCC14945 (pLMS 1180) enzyme with activity 5 times higher than that of the gene donor cells. While E. coli secreted about 7% of the produced enzyme, B. subtilis excreted the enzyme into the medium wholly and B. megaterium about 97% of the total product. The SDS-PAGE of this enzyme produced in E. coli (pLMS1180), B subtilis (pLMS1180) or B. megaterium (pLMS1180) indicated a molecular weight of 38,000. The enzymes overproduced in three different host cells hydrolyzed laminarin to produce mainly laminaribiose, laminaritriose, and laminarioligosaccharides. The plasmid pLMS1180 was stable in B. megaterium, E. coli, but was unstable in B. subtilis.

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A Study on the Utilization of Trichoxanthes Kirilowii Root Starch (하늘타리(Trichoxanthes Kirilowii)의 자원화(資源化)에 관한 기초(基礎) 연구(硏究))

  • Koh, Jeong-Sam
    • Applied Biological Chemistry
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    • v.24 no.1
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    • pp.59-66
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    • 1981
  • Trichoxanthes Kirilowii with high starch-content was investigated to utilize as a food source. The weight and starch content of Trichoxanthes Kirilowii roots increased rapid1y in proporion to the growth period. The seasonal variations of the starch content were $36.5{\sim}48.0%$ (dry basis) from June to December. The chemical properties of natural growth soils of Trichoxanthes Kirilowii contained more organic matter and total nitrogen content than citrus orchard soils, but less mineral; P,K,Ca and Mg. To prepare starch with the plant root, the centrifugal method(3,000 rpm, 20 min) obtained the highest yield. The industrial-scale method, was similar to the processing of sweetpotato starch (tank precipitation method), and was good in quality. The starch granules were mainly spherical with diameters ranging from $5{\sim}16{\mu}$. The density of the starch was 1.535 and amylose content was about 26.7%. The X-ray diffraction pattern showed that the granules were of the B-type. The blue value of starch, amylose and amylopectin was 0.46, 0.80 and 0.18, respectively. The starch contained 0.05% ash, 0.35% crude protein and 34 mg% phosphorus. and had an inital pasting temperature of $63.5^{\circ}C$. The color intensity of the starch which iodine gave rise to absorption maxima at 670nm. The starch paste showed high stability during cold storage at $5^{\circ}C$.

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Analysis of Oil Performance by Different Type of Engine Oil In the Field (필드조건, 엔진오일의 종류에 따른 오일성능 분석)

  • Kim, Young Whan;Song, Jun Hee;Kim, Han Joo
    • Journal of Energy Engineering
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    • v.26 no.3
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    • pp.131-136
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    • 2017
  • Automobile engine oil is the most important lubricant for operating as the engine is started. Recently, manufacturers of the automotive industry and lubricants are considerably improving the quality of oil with additive to extend change cycle period. Most customers are recommended genuine oil among different types from shop expert. Through this report we suggest another reference point for consumer to pick highly efficient lubricant. This report is investigated oil compounds to compare with 6 different automotive considering actual running condition for 7 months. we conducted experiment from physical and chemical perspectives. In the field, through various experiments oil compounds between mineral oil and synthetic oil are largely distinguished in oxidation, viscosity, fluid and TBN. These are influenced by engine part wear as piston, bearing etc. Comparing various investigation with different oil the performance of synthetic oil is shown better condition in flash point, oxidation stability and also found less in change pollutant iron, Al compounds. Additives of oil show clear difference Ca level in detergent-dispersant both mineral oil and synthetic oil. And Zn in extreme pressure additives and P in Lubricity improver make no difference to both.

Quantitative Changes of Cholesterol Oxides Formed in Butter under Varied Storage Conditions (상이한 조건에서 저장한 버터로부터 생성된 콜레스테롤 산화물의 양적변화)

  • Chang, Young-Sang;Yang, Joo-Hong;Shin, Hyo-Sun
    • Korean Journal of Food Science and Technology
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    • v.22 no.7
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    • pp.767-773
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    • 1990
  • The effect of storage conditions on the oxidative stability of cholesterol in butter was studied by quantifying cholesterol oxides by GC-MS. Experimental variables for storage conditions were packaging, storage temperature, light source, and storage period. No cholesterol oxides were detected from packaged butter under all storage conditions. When unpackaged butter was stored under ultraviolet light at ambient temperature, $7{\alpha}-hydroxycholesterol,\;7{\beta}-hydroxycholesterol$, cholesterol ${\beta}-epoxide$, cholesterol ${\alpha}-epoxide$, cholestane-triol were detected after 2, 4, 6 and 8 weeks of storage. The amounts of cholesterol oxide species produced were different depending on the storage periods. The amounts of each cholesterol oxides, $7{\alpha}-hydroxycholesterol,\;7{\beta}-hydroxycholesterol$, cholesterol ${\beta}-epoxide$, cholesterol ${\alpha}-epoxide$, and cholestane-triol, produced after 2 weeks of storage were 34.2, 14.0, 12.1, 1.30, and 0.50 ppm, respectively, and after 8 weeks of storage were 68.1, 29.1, 56,3, 8.50, and 4.00 ppm, respectively with trace amounts of 3,5-cholestadien-7-one. When fluorescent light was used instead of ultraviolet light with other conditions remained the same, the same species of cholesterol oxides were detected but with lesser amounts.

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Stability of Lipids in Ramyon (deep fat fried instant noodle) -I. Oxidative Changes in the Ramyon Lipids during Storage- (라면 유지(油脂)의 안전성(安定性)에 관한 연구(硏究) -(I) 시험저장중(試驗貯藏中) 라면유지(油脂)의 산패(酸敗)에 대(對)하여-)

  • Cheigh, Hong-Sik;Kwon, Tai-Wan
    • Korean Journal of Food Science and Technology
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    • v.4 no.4
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    • pp.259-264
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    • 1972
  • Oxidative changes of the Ramyon lipids were studied under three experimental storage conditions. Ramyon was 1) exposed to fluorescent light irradiation at $25^{\circ}C$, 2) incubated in the dark at $40^{\circ}C$ and 3) irradiated with ultra-violet light at $25^{\circ}C$. In the study, changes in acid value, peroxide value, carbonyl value, TBA number, fatty acid composition and iodine value were determined with the lipids extracted from the Ramyon samples in intervals for a period of 20 weeks. Acid value, peroxide value, and TBA number of the samples under fluorescent light irradiation and $40^{\circ}C$ incubation increased slightly during storage, while a sharp increase of those values were noticed with the samples of ultra-violet light irradiation. Especially, the TBA number of the Ramyon lipid under ultra-violet light irradiation markedly increased within 10 weeks and then decreased. With this change in TBA number, however, the bound form of malonaldehyde increased gradually. During the storage under $40^{\circ}C$ incubation, and ultra·violet irradiation for 10 weeks, the content of linoleic and linolenic acids decreased, while palmitic and stearic acids increased. However, only small changes were noticed in iodine value of the samples. On the other hand, oxidative rancid odor appeared at the end of 16 weeks storage under fluorescent light irradiation and $40^{\circ}C$ incubation, while it took only 4 weeks with the sample stored under ultra-violet irradiation.

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A Study on the Durability and Environmentally Friendly of Inorganic Grouting Material (무기질계 지반주입재의 내구성 및 친환경적 특성에 관한 연구)

  • Chun, Byungsik;Park, Dukhyum;Kang, Hyoungnam;Do, Jongnam
    • Journal of the Korean GEO-environmental Society
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    • v.9 no.5
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    • pp.37-43
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    • 2008
  • Inorganic injection material, which is one of the ground improvement materials, consists of cement accelerator and inorganic micro particle. The inorganic injection material is known to overcome the major limitations of water glass type improvement materials, which are leaching and accompanying strength loss. The inorganic injection material is superior in durability and strength, and environmentally friendly since leaching is prevented. In this study, the effectiveness and environment-friendliness of the MIS(Micro Injection-process System) using the inorganic injection material is compared to SGR, which uses the water glass. The performed tests were unconfined compression test, chemical resistance test, and fish poison test. The unconfined compression tests showed that the MIS results in 1.7 times higher 28 day strength compared to the SGR. In addition, the strength continually increased with time for the MIS, while it decreased for the SGR. The chemical resistance tests indicated that the rate of change in length using the MIS is 10~25 times smaller than when using the SGR. The fish poison test proved that MIS was more environmentally friendly. The analysis of chemical ingredients of leached showed that the amount of $Cr^{6+}$, Pb and Si leached from the MIS is less compared to the SGR. Accordingly, the MIS grout is more high-strength than existing SGR grout. It is excellent in shortening of construction period, structural stability of foundation and environmentally friendly. So, it is considered that it has not little the problem about groundwater pollution.

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Osteoarthritis of the Temporomandibular Joint (측두하악관절의 골관절염)

  • Lee, Jeong-Yun
    • Journal of Oral Medicine and Pain
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    • v.38 no.1
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    • pp.87-95
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    • 2013
  • Osteoarthritis (OA) of the temporomandibular joint (TMJ) is a severe form of temporomandibular disorders (TMDs), presenting gradual breakdown of articular cartilage and subchondral bone by the functional load sustained to exceed the physiologic tolerance of the joint. In such a joint loaded, offensive bioactive materials such as matrix degrading proteins, cytokines, and free radicals increase in concentration to shift the tissue response in the joint to degeneration from regeneration or remodeling. Recently, it has been issued that obesity can play an offensive role in pathogenesis of OA in a metabolic way. Adipokines released by adipose cells are present at higher concentration in the arthritic joint and joints of obese individuals. However, because of conflicting data reported, further scientific study should be performed to elucidate the practical role of adipokines in pathogenesis of TMJ OA. As far as the clinical signs and symptoms of TMJ OA are not much different from those of other forms of TMD and any definitive treatment modality to control directly the bone resorptive activity is not available yet, the treatment of TMJ OA should be directed to reduce the physical load and enhance the physiologic tolerance of the joint by means of conservative treatment such as physical therapy, medication, and occlusal splint therapy for sufficient period and, if needed after that, supplementary surgical procedure such as intra-articular injection, arthrocenthesis, and arthroscopic surgery that have turned out to be effective to control OA signs and symtpoms. Enthusiastic reassurance and motivation for patients to control behaviors for themselves to reduce unnecessary functional load in daily life is very important for the joint to reach to more favorable orthopedic stability of the TMJ more quickly, guaranteeing more successful management TMJ OA.