• 제목/요약/키워드: total nitrogen storage

검색결과 340건 처리시간 0.023초

살균 된장의 저장과정 중 품질변화 (Quality Changes of Sterilized Soybean Paste during Its Storage)

  • 오만진;김종생;최성현;이상덕;이규희
    • 한국식품영양과학회지
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    • 제28권5호
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    • pp.1069-1075
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    • 1999
  • The sterilization was attempted to improve the quality deterioration of soybean paste during its storage. For this experiment, soybean paste was sterilized at 80oC for 30 minutes and stored during 6 months at 15oC and 30oC, respectively. The total approximate composition contents were moisture 52.5%, crude protein 11.94%, crude fat 2.0%, amino nitrogen 413.3mg%, sodium chloride 11.61% and ash 15.5%. According to the increase of storage period, pH was decreased gradually because of the increase of organic acids by the metabolism of microorganisms and the acid accumulation by acid forming bacteria, but titratable acidity was increased during storage. Amino nitrogen was rapidly increased for the first one or two month storage period and maintained as the same level for the rest of them. Each amino acid contents of soybean paste, which were glutamic acid, tryptophan, proline, arginine, and aspartic acid, had much higher level than others. In color changes sterilized soybean paste(SSP) was much lower than that of raw ones(RSP). Hunter L and b values on the surface of soybean paste were decreased during storage, and the decreasing levels were higher at 30oC than at 15oC. Hunter a value, however, was increased a little in the initial storage, and thereafter it was decreased. Lactic acid bacteria, yeasts, and molds were disappeared completely by the sterilization. However, the bacteria of aerobes and anaerobes were not disappeared by this processing.

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파쇄(破碎)고구마의 밀봉저장중(密封貯藏中) 화학성분(化學成分)의 변화(變化) (Chemical Changes during the Storage of Sweet potatoes Crushed and Sealed up with Polyethylene Film)

  • 김승겸;김성열
    • 농업과학연구
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    • 제11권1호
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    • pp.45-52
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    • 1984
  • Changes of chemical componts and populations of total bacteria and lactic acid bacteria were examined during a month-long storage of sweet potatoes crushed and sealed up with polyethylene film at $7-8^{\circ}C$. 1. Changes of starch, total protein, volatile acid and ammonia-nitrogen contents were li 2. In a three days, pH down and increase of non-volatile acid content were notable, populations of total bacteria and lactic acid bacteria were maximum. 3. Vitamic C and soluble sugar contents tended to be reduced during the storage and the leftover were 75-85% and 41-45% respectively. 4. ${\beta}$-Amylase activity decreased gradually and vanished 15-30days. 5. Variations of chemical compontents of the samples inoculated lactic acid bacteria were larger than non- treated to some extent. 6. As above results, mainly homo lactic acid fermentation was done in this storage condition.

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수삼의 저장조건에 따른 홍삼의 이화학적 특성 (Physicochemical Properties of Red Ginseng on Storage Condition of the Fresh Ginseng)

  • 김천석;정인찬;김세봉;양덕춘
    • 한국약용작물학회지
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    • 제13권1호
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    • pp.52-56
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    • 2005
  • 본 연구는 수삼의 저장기간 (무저장, 2일, 6일, 8일, 10일) 및 저장온도 $(20^{\circ}C,\;34^{\circ}C,\;-10^{\circ}C)$로 구분하여 제조된 홍삼의 품질 및 이화학적 특성변화를 비교 조사하였다. 수삼의 수분함량은 저장일이 길어질수록 감소하는 경향이었다. 수삼을 10일동안의 단기간 저장온도는 $34^{\circ}C$의 냉장저장이 적합하다고 생각한다. 전질소 함량은 저장일 10일로 갈수록 무저장구에 비해 다소 증가하는 경향이었다. 저장온도별로는 실온, 냉동, 냉장저장 순으로 무저장구보다 전질소 함량이 증가함을 보였다. 각각의 저장구별 페놀성 화합물의 함량은 무저장구에 비하여 저장기간이 길수록 증가하는 경향이었다. 저장 온도별로는 냉장 저장구가 실온, 냉동 저장구에 비하여 다소 페놀성 화합물의 함량이 높았다. 저장조건별 홍삼의 사포닌 Rf 에 대한 8종의 $ginsenoside\;Rb_1,\;Rb_2,\;Rc,\;Rd,\;Re,\;$Rg_3,\;Rg_1,\;Rg_2$의 상대적 함량 (%)비 변화를 분석한 결과, 각각 저장조건에서 Rf 대한 $Rb_1,\;Rg_1$의 상대적 함량비가 저장기간이 늘어날수록 감소하는 경향이었다. 기타 ginsenoside 함량변화는 시료간의 차이에서 나타난 것으로 판단되며 저장조건에 따른 변화 경향은 뚜렷하지 않았다. 관능적 성질에서 각각 저장구별로 홍삼의 품질, 맛과 향을 종합적으로 평가하여 볼 때, $34^{\circ}C$에서 냉장저장 운반하는 것이 홍삼 향미의 안정적 유지에 가장 적합한 것으로 평가되었다.

우렁쉥이 이용에 관한 연구 -7. 우렁쉥이 젓갈의 제조 및 품질평가(III)- (Utilization of Ascidian, Halocynthia roretzi -7. Processing and Quality Evaluation of Fermented Ascidian(III)-)

  • 이강호;조호성;이동호;김민기;조영제;서재수;김동수
    • 한국수산과학회지
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    • 제26권4호
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    • pp.340-345
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    • 1993
  • 우렁쉥이 젓갈의 실용화를 위하여 적정 효소 및 숙성 조건을 토대로 하여 상온에서 $1{\sim}2$일간 숙성 시킨 후 저온 저장하였을 때의 젓갈의 품질 변화를 살펴본 결과는 다음과 같다. 1. 저온 저장중 아미노질소는 서서히 증가하였으나 식염 농도가 높은 것이 다소 낮았다. 휘발성염기질소도 서서히 증가하였는데 papain이나 protease-A를 첨가한 경우는 식염 $5\%$때 저장 30일경, $10\%$$15\%$의 경우는 약 40일경에 $35mg/100g$에 달하였다. Total creatinine의 변화는 저장 20일까지 증가한 후 감소하는 경향이었고 total carotenoid는 감소하는 경향이었다. 2. 저장중 환원당은 증가하였으며 복합효소인 protease-A를 첨가한 경우가 환원당 생성이 월등히 높았다. Glycogen은 감소하는 경향이었는데 특히 protease-A는 식염 $5\%$$10\%$를 첨가한 경우는 저장 30일경에 식염 $15\%$의 경우는 저장 40일경에 완전히 소실되었다. 저장중 갈변도는 큰 변화는 없었다. 3. 저온 저장중 관능 검사 결과 $0.1\%$ papain과 $0.1\%$ protease-A에 식염 $5\%$를 첨가한 경우 저장 30일경부터, 식염 $10\%$$15\%$를 첨가한 경우는 저장 40일경에 우렁쉥이 특유의 상큼한 향기와 맛이 퇴조하였다. 따라서 여러 가지 화학적 분석 결과와 관능적 품질 평가를 종합하여 볼 때 상온 숙성 후 저온 저장시 식염 농도에 따라 $20{\sim}40$일까지는 우렁쉥이 특유의 향기와 우렁쉥이 젓갈 특유의 맛을 유지할 수 있었으나 장기간의 연장을 위해서는 저장온도의 저하와 퇴색 방지를 위한 항산화제 또는 보장제를 보조적으로 첨가해야 할 것으로 생각된다.

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미가공 잎담배 저장 중 색상, 화학성분 및 끽미 변화 (Changes of Chromatic, Chemical and Organoleptic Characteristics of Green Leaf Tobaccos during Storage in Warehouse)

  • 정기택;안대진;이종률;김상범
    • 한국연초학회지
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    • 제24권2호
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    • pp.88-93
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    • 2002
  • This study was carried out to investigate the changes of chromatic, chemical and organoleptic characteristics of green leaf tobaccos during storage in warehouse. Eight grades(flue-cured ; A2O, B2O, C2L and D2L, burley ; A2T, B2T, C2W and D2W) of green loaves produced in 2001 were stored during 8 months(Oct. 30, 2001 to Jun. 30, 2002) in warehouse of Kimcheon(flue-cured) and Namwon(burley) Leaf Tobacco Processing factory, respectively. Moisture contents of D2L in flue-cured and four grades in burley were significantly decreased during storage in warehouse. Redness(a) values of six grades except for D2L and D2W were significantly increased during storage. Lightness(L), yellow(b) and pH values, and the contents of nicotine, total nitrogen and total sugar were not changed during storage. Irritations of flue-cured tobacco were increased, whereas tastes were decreased during storage. Irritations and tastes of burley tobacco were little changed during storage. The result suggests that the flue-cured green leaf being processed as early as possible for minimizing the deterioration of smoke taste during storage in warehouse.

자외선 처리가 반염건 고등어 필레의 냉장저장중 품질변화에 미치는 영향 (Quality changes of salted and semi-dried mackerel fillets by UV treatment during refrigerated storage)

  • 송효남;이대규;한성욱;윤혜경;황인경
    • 한국식품조리과학회지
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    • 제21권5호
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    • pp.662-668
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    • 2005
  • To investigate the quality retention method of salted and semi-dried mackerel fillets, pH, volatile basic nitrogen (VBN), trimethylamine (TMA) and total bacterial counts in the fillets that were UV treated for 1, 3, and 4 hr were periodically measured during 48 days of refrigerated storage. The moisture, crude protein, crude lipid, and ash contents were 45.46 %, 18.87 %, 33.75 %, and 2.99 %, respectively. The freshness as determined by pH measurement could be maintained up to 25 days for the control and 31 days for the UV-treated fillets. VBN contents were continually increased over the storage time. The control reached the initial putrid level after 21 days while the UV-treated fillets after $25{\sim}31$ days. A similar tendency was shown for the changes of trimethylamine TMA contents, although the period differed slightly and the increase of the UV treatment time could decrease the TMA contents. The changes on the total bacterial counts of the fillets were maintained under 105 CFU/g during 48days. Especially, due to the effective decrease of the microorganism count by UV treatment at the beginning of the storage, UV -treated fillets showed lower bacterial counts than control over the whole period. E. coli. and Listeria were not detected in any fillets. Combining the above data and the sensory changes, the storage period of the fillets could be prolonged from 15 days at present to 30 days by UV treatments.

생약성분을 첨가한 소시지의 저장성에 대한 연구 (The Effect of Medicinal Plants with Additives on Storage Characteristics of Sausage)

  • 임혜경;조은자
    • 동아시아식생활학회지
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    • 제12권3호
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    • pp.249-257
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    • 2002
  • This study was conducted to investigate the effects of medicinal plants with additives on storage characteristics of sausage. The water activity of the sausage with the additives tended to decrease with the storage time: the highest value was shown in the Angelica added sausage samples, in both cases added with dried powder as well as with extracted powder. The Paeonia extract powder added sausage had the lowest pH value. The herbal plant added sausages showed the lowest cooking and storage losses among all. The values of TBA (thiobarbituric acid value) and VBN (volatile basic nitrogen) increased with storage time, but the values of the sample with the extract powder additive were lower than those of the freeze-dry powder additive. Total plate counts of bacteria increased with storage time fur all samples, but those for the samples with Pueraria, Platycodon, Angelica, Bupleurum and Paeonia additives exhibited lower values than the control. From the above results, the sausages with medicinal plant additives showed the superior storage safety and quality characteristics.

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복합 박테리오신의 항균활성 및 축산식품 저장성 증진 효과 (Antimicrobial Effects of a Bacteriocin Mixture from Lactic Acid Bacteria against Foodborne Pathogens)

  • 한경식;오세종;문용일
    • 한국축산식품학회지
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    • 제22권2호
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    • pp.164-171
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    • 2002
  • 박테리오신을 생산하는 9종의 유산균 배양액으로부터 ammonium sulfate를 첨가하여 제조된 각각의 조박테리오신을 혼합하여 복합박테리오신용액을 제조하였다. 복합박테리오신의 항균 활성은 단일 박테리오신보다 우수하였으며 항균 범위 또한 넓어짐을 알 수 있었고 단일 박테리오신에 대하여 저항성을 나타내는 Listeria monocytogenes의 생육을 저해하는 것으로 나타났다. 또한, 복합박테리오신은 pH와 열에강한 안정성을 보여 식품 가공 중에도 이용이 가능한 것으로 나타났다. 복합박테리오신을 프랑크소세지, 모짜렐라 치즈 및 돈육등심근에 첨가한 후 저장기간별 일반세균수의 변화를 조사한 결과, 대조구에 비해 유의적인 감소현상을 나타내었고 저장 28일 경과 후에는 모든 식품에서 1/10 또는 1/100 정도로 식품내 총세균이 억제되었다. 또한, 저장기간 중 VBN의 함량을 조사한 결과 돈육등심근과 모짜렐라 치즈의 경우 14일 이후부터 박테리오신 처리구가 대조구에 비해 유의적으로 낮은 수치를 보여주었다.

Effect of Long Term Fertilization on Soil Carbon and Nitrogen Pools in Paddy Soil

  • Lee, Chang Hoon;Jung, Ki Youl;Kang, Seong Soo;Kim, Myung Sook;Kim, Yoo Hak;Kim, Pil Joo
    • 한국토양비료학회지
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    • 제46권3호
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    • pp.216-222
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    • 2013
  • Fertilizer management has the potential to promote the storage of carbon and nitrogen in agricultural soils and thus may contribute to crop sustainability and mitigation of global warming. In this study, the effects of fertilizer practices [no fertilizer (Control), chemical fertilizer (NPK), Compost, and chemical fertilizer plus compost] on soil total carbon (TC) and total nitrogen (TN) contents in inner soil profiles of paddy soil at 0-60 cm depth were examined by using long-term field experimental site at $42^{nd}$ years after installation. TC and TN concentrations of the treatments which included N input (NPK, Compost, NPK+Compost) in plow layer (0-15 cm) ranged from 19.0 to 26.4 g $kg^{-1}$ and 2.15 to 2.53 g $kg^{-1}$, respectively. Compared with control treatment, SOC (soil organic C) and TN concentrations were increased by 24.1 and 31.0%, 57.6 and 49.7%, and 72.2 and 54.5% for NPK, Compost, and NPK+Compost, respectively. However, long term fertilization significantly influenced TC concentration and pools to 30 cm depth. TC and TN pools for NPK, Compost, NPK+Compost in 0-30 cm depth ranged from 44.8 to 56.8 Mg $ha^{-1}$ and 5.78 to 6.49 Mg $ha^{-1}$, respectively. TC and TN pools were greater by 10.5 and 21.4%, 30.3 and 29.6%, and 39.9 and 36.3% in N input treatments (NPK, Compost, NPK+Compost) than in control treatment. These resulted from the formation and stability of aggregate in paddy soil with continuous mono rice cultivation. Therefore, fertilization practice could contribute to the storage of C and N in paddy soil, especially, organic amendments with chemical fertilizers may be alternative practices to sequester carbon and nitrogen in agricultural soil.

Effects of Storage Duration and Temperature on the Chemical Composition, Microorganism Density, and In vitro Rumen Fermentation of Wet Brewers Grains

  • Wang, B.;Luo, Y.;Myung, K.H.;Liu, J.X.
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권6호
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    • pp.832-840
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    • 2014
  • This study aimed to investigate the effects of storage duration and temperature on the characteristics of wet brewers grains (WBG) as feeds for ruminant animals. Four storage temperatures ($5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$) and four durations (0, 1, 2, and 3 d) were arranged in a $4{\times}4$ factorial design. Surface spoilage, chemical composition and microorganism density were analyzed. An in vitro gas test was also conducted to determine the pH, ammonia-nitrogen and volatile fatty acid (VFA) concentrations after 24 h incubation. Surface spoilage was apparent at higher temperatures such as $25^{\circ}C$ and $35^{\circ}C$. Nutrients contents decreased concomitantly with prolonged storage times (p<0.01) and increasing temperatures (p<0.01). The amount of yeast and mold increased (p<0.05) with increasing storage times and temperatures. As storage temperature increased, gas production, in vitro disappearance of organic matter, pH, ammonia nitrogen and total VFA from the WBG in the rumen decreased (p<0.01). Our results indicate that lower storage temperature promotes longer beneficial use period. However, when storage temperature exceeds $35^{\circ}C$, WBG should be used within a day to prevent impairment of rumen fermentation in the subtropics such as Southeast China, where the temperature is typically above $35^{\circ}C$ during summer.