• Title/Summary/Keyword: moisture content for safe storage

검색결과 18건 처리시간 0.02초

벼의 안전저장기간 (Safe Storage Period of Paddy under Different Temperature and Moisture Content Conditions)

  • 김의웅;김동철
    • 한국식품저장유통학회지
    • /
    • 제11권2호
    • /
    • pp.257-262
    • /
    • 2004
  • 본 연구는 벼의 함수율 및 온도별 안전저장기간을 구명하기 위하여 수행되었다. 벼의 함수율은 16.1∼22.2%범위에서 4수준, 온도는 10∼3$0^{\circ}C$에서 3수준으로 저장하면서 외관, 발아율, 지방산가를 측정하였고, 안전저장기간의 온도 및 함수율 의존성을 분석하였다. 그 결과를 요약하면 다음과 같다. 벼의 발아율은 저장온도가 증가할수록, 함수율이 높을수록 급격하게 저하한 반면, 지방산가는 저장기간에 따라 증가하였으나 온도보다는 함수율에 의한 영향이 크게 나타났다. 벼의 온도 및 함수율이 높을수록 변색립 및 곰팡이는 빨리 발현되었으며, 함수율 16.1%에서는 온도가 높아도 저장기간 내에 부패현상은 나타나지 않았다. 발아율, 지방산가 및 외관에 의한 저장가능기간 중 최소가 되는 저장기간으로 온도 및 함수율에 따른 안전저장기간을 제시하였다.

동결건조 분말된장의 흡습 거동에 대한 속도론적 연구 (Kinetic Study for Hygroscopic Behavior of Freeze Dried Soy Paste Powder)

  • 황응수;이철원;유주현;이신영
    • 한국식품과학회지
    • /
    • 제19권3호
    • /
    • pp.231-238
    • /
    • 1987
  • 서로 다른 외관색택을 갖는 (적갈색 및 담백색) 2종의 된장을 동결건조하고 분말화 하였다. 이들의 흡습거동을 여러 수분찰성도$(0.11{\sim}0.88)$ 및 서로 다른 세온도(25, 40 및 $50^{\circ}C$)에서 조사하였으며, 품질 특성 및 저장안정성의 관점에서 동력학적 및 열역학적 해석을 하였다. 시료 분말된장의 등온수분흡착은 BET분류에 따른 typell에 속하였고, Henderson의 경험식으로 잘 설명할 수 있었다. Caurie식으로부터 계산한 저장 안전수분량은 온도에 의존하였으며 $5.5{\sim}3.98%$(건량기준)범위 이었다. 수분흡습과정은 평형수분함량과 임의의 수분함량과의 차이에 대한 1차 속도식에 따랐으며, 초기에 높은 흡습성을 나타내는 특징을 보였다. 분산성 및 색차의 변화는 저장수분활성도에 민감한 의존성을 보였으며, 최대의 저장안정성은 저장안전 수분함량수준에서 나타났다. 또한, 수분함량에 대한 열역학적 변수의 변화도 저장안전 수분함량수준에서 유의성이 있었으며, 분말된장이 저장안정성과 높은 상관성을 갖는 것으로 나타났다.

  • PDF

백미 제조방식에 따른 저장특성 (Storage characteristics of milled rice according to milling system types)

  • 김의웅;김훈;한재웅;이효재
    • 한국식품저장유통학회지
    • /
    • 제21권3호
    • /
    • pp.308-314
    • /
    • 2014
  • 본 연구는 제조방식별로 제조된 씻지 않는 쌀의 저장특성을 조사하기 위하여 최근 개발된 건식(DT), 반건식(SDT) 및 가수정미방식(WT)의 제조 시스템으로 공시재료를 조제한 후 저장기간과 저장온도에 따른 품질특성을 분석하여 수행하였다. 공시재료는 각각 백도가 41(DT1, SDT1, WT1)과 43(DT2, SDT2, WT2)의 두 가지 수준으로 조제하였으며, 저장기간은 약 12주이었고, 저장온도는 각각 10, 20 및 $30^{\circ}C$로 설정하였다. 저장기간 동안의 품질특성을 살펴본 결과 색도 b값과 지방산가는 점차 증가하는 경향을 나타내었으며, 백도, 함수율, 탁도, 건고물량 및 총균수는 감소하는 경향을 나타내었다. 그러나 백도, 색도 b값, 탁도 및 건고물량은 저장초기인 1주차 이후부터는 변화가 적게 나타났다. 반면 함수율, 총균수, 지방산가는 제조방식보다 저장온도의 영향이 큰 것으로 나타났으며, 저장온도가 높을수록 함수율과 지방산가는 감소폭이 크게 나타났고, 총균수는 증가폭이 크게 나타났다. 또한 함수율, 탁도, 건고물량은 제조방식의 영향을 받아 가수정미방식으로 제조된 시료의 경우에는 각 항목의 초기값이 다른 제조방식과 차이가 큰 것으로 나타났다. 가수정미방식으로 제조된 시료(WT1, WT2)의 초기함수율은 높게 나타났으며, 탁도 및 건고물량은 다른 제조방식의 시료보다 낮게 나타났으나, 저장기간이 경과함에 따른 감소폭은 비슷한 것으로 나타났다. 따라서 본 연구에서는 건식, 반건식 및 가수정미방식으로 제조한 백미는 저장온도와 저장기간이 증가할수록 저장성이 떨어지는 경향을 나타내었고, 특히 가수정미방식으로 제조된 시료는 초기 품질특성 중 함수율이 높게 나타나 저장중의 산패에 영향을 주는 지방산가가 증가하여 저장성이 낮은 것으로 판단되었다.

산채의 건조 특성에 관한 연구 (Study on the Drying Characteristics of Wild Vegetables)

  • 임종환;황금택
    • 한국식품과학회지
    • /
    • 제27권3호
    • /
    • pp.358-364
    • /
    • 1995
  • 건조산채의 안전저장 수분함량을 결정하기 위하여 네 가지 채소 즉, 호박고지, 고구마줄기, 토란대, 및 도라지의 건조특성과 등온흡습특성을 조사하였다. 이들 채소의 건조곡선은 초기의 평형조절기간과 항률건조기 및 감률건조기간의 3단계로 뚜렷하게 구분이 되었으며, 감출건조기는 종류에 따라 다시 $2{\sim}3$단계로 구분되었다. 감률건조곡선은 섬유질상 식품의 건조 특징인 위로 볼록한 형태를 보였으며, 임계수분함량은 호박고지가 $8.29{\sim}9.75$, 고구마줄기가 $10.40{\sim}15.08$ 토란대가 $9.51{\sim}14.52$, 도라지가 $3.29{\sim}3.56g\;H_2O/g$ dry solids였다. 감률건조기간 중의 건조속도에 대한 활성화에너지값은 호박고지가 2.30, 고구마줄기가 2.11, 토란대가 4.97, 도라지가 2.80 kcal/mol이었다. 각 채소의 단분자층 수분함량값은 건조시의 임계수분함량값과 유사하였는데, 호박고지가 $10.05{\sim}13.59$, 고구마줄기가 $9.49{\sim}12.69$, 토란대가 $9.50{\sim}16.48$, 도라지가 $5.01{\sim}5.44g\;H_2O/g$ dry solids였다. 결과적으로 이들 채소를 안전하게 저장하기 위해서는 수분함량을 단분자층 수분함량 이하로 또는 임계수분함량 이하로 건조시킬 필요가 있음을 알 수 있다.

  • PDF

건조 및 초저온 처리에 의한 뽕나무 종자의 장기 보존 (Cryopreservation of Mulberry(Morus) Seeds in Liquid Nitrogen(L$N_2$))

  • 최영철;류근섭;방혜선
    • 한국잠사곤충학회지
    • /
    • 제42권1호
    • /
    • pp.1-5
    • /
    • 2000
  • To investigate the possibility of crypreservation of mulberry seeds in liquid nitrogen(LN$_2$), characteristics of the seeds were examined after picking mulberry syncarps and drying-heat treatment. Storage in LN$_2$has the potential of providing indifinite preservation of valuable seed germplasm. Determining the tolerance of seeds among given cultivars to LN$_2$cooling and subsequent rewarming is the first step to establishing the feasibility of LN$_2$storage. Seeds of 4 mulberry varities were treated to LN$_2$(-196$\^{C}$) for 24 hours after drying heat treatment. Seed moisture content of Daeryukppong was the highest. As moisture content of mulberry seed was below 1%, storage in LN$_2$was safe. And drying heat treatment for 60 minutes was suitable to prevent decreased germination rate and germination vigor of seeds. The seeds of Cheongilppong were unsuibable to cryopreserve in LN$_2$for longterm storage.

  • PDF

쌀의 저장중 수분이동에 의한 균열현상에 관한 연구 (Cracking of Rice Caused by Moisture Migration during Storage)

  • 목철균;이상기
    • 한국식품과학회지
    • /
    • 제31권1호
    • /
    • pp.164-170
    • /
    • 1999
  • 저장 중 쌀의 수분이동에 따른 균열현상을 구명하고 균열을 발생시키는 임계조건을 산출하여 이를 토대로 쌀의 균열을 방지할 수 있는 저장조건을 확립하였다. 쌀의 평형상대습도와 노출된 환경의 상대습도의 차이$({\Delta}ERH)$가 적을 때는 균열이 발생하지 않은 반면, 그 차이가 임계치보다 클 때는 균열이 발생하였으며 균열의 발생정도는 쌀의 평형상대습도와 환경의 상대습도의 차이가 클수록 심하게 나타났다. 탈습환경 하에서는 불규칙한 형상의 균열이 쌀알의 외부에 발생하였으며 흡습환경 하에는 규칙적인 형상의 균열이 쌀알의 내부에 축방향과 수직방향으로 방사상으로 발생하였다. 노출시간별 균열발생 패턴을 Weibull함수에 의거하여 해석한 결과, ${\Delta}ERH$가 클수록 균열속도상수가 증가하였다. 동할미 발생률은 In$({\Delta}ERH)$에 따라 직선적으로 증가하였으며, 임계 균열발생 상대 습도차(critical crack-inducing ${\Delta}ERH$)는 탈습시 $11.3{\sim}16.4%$, 흡습시 $10.8{\sim}17.1%$의 값을 보였다. 실험결과를 토대로 수분함량 및 수분활성도 별 쌀의 안전저장 상대습도를 나타내는 diagram을 제시하였다.

  • PDF

소형 교반식 저장건조빈의 벼 건조 및 저장 특성 (Drying and Storage Characteristics of Small Scale Accumulated / Stirred Storage and Drying Bin)

  • 박종원;녕효봉;차영욱;강태환;한충수;조성찬
    • Journal of Biosystems Engineering
    • /
    • 제36권3호
    • /
    • pp.195-203
    • /
    • 2011
  • Not only does the labor of manufacturers used most in the drying process after rice harvest, but it also is having huge influence in quality. Also, because drying storage of rice production around the whole country is scarce with original facility, it has become a very important matter that farms develop their own safe and high-quality facilities to store and dry rice. Therefore, this study developed a small scale accumulated storage and drying bin, assessed nalyzed drying properties, and conducted analysis of research on the property of quality when storing for a long time. As a result, the drying speed of the small scale accumulated storage and drying bin was adequate of 0.042%/hr and was shown that the experimental static pressure and theoretical static pressure corresponded. Also, it was shown that drying cost was up to about 6 times inexpensive that heated air drying. For the storage of the small scale accumulated storage and drying bin, average of moisture content was around 16.5 until early April and decreased to 15.7% in July. Inside storage was maintained to 12.13% until early April and slightly increased to 14% after May. It was shown that inside storage had higher hardness and rate of cracking than the small scale accumulated storage and drying bin by storage conditions and germination rate was shown a little higher when stored in the small scale accumulated storage and drying bin.

노티의 재료에 따른 이화학적, 관능적 및 기계적 특성 연구 -제 1보 : 찹쌀 노티의 이화학적, 관능적 및 기계적 특성 연구- (Effect of Cereals on the Physicochemical and Sensory Characteristics of Noti -I. Study on the Physicochemical and Sensory Characteristics of Glutinous rice Noti -)

  • 임희정;염초애
    • 한국식품조리과학회지
    • /
    • 제12권1호
    • /
    • pp.60-73
    • /
    • 1996
  • This study was undertaken to investigate the effect of cereals on the physicochemical and sensory characteristics of Noti. Noti is one of Korean traditional pan-fried glutinous cereal cakes. Noti made from the steamed glutinous rice flour, glutinous Chinese millet flour, glutinous millet flour or glutinous Indian millet flour is saccharified with malt, and then pan-fried. Noti also has sweet taste without sugar added. In addition, Noti has elastic characteristic, high calorie and good flavor. Long storage makes it better taste. In this case, Noti was made from the steamed glutinous rice flour. By the sensory evaluation, color, flavor and moistness were unfavorable according to the storage. Consistency was not strongly increased when comparing with the common rice cake depending upon the storage. The texture tended to increase by storage period. Optimum conditions of the safe storage and overall acceptability were to add 15% malt and keep 6hr saccharification time at 60$^{\circ}C$. During the period of storage for 90 days, reducing sugar content was similar, moisture content was low and maintained, and the acid value was not increased abruptly. The hardness was not increased rapidly and fungal growth was considerably low. Cohesiveness and elasticity were increased during storage.

  • PDF

Effect of cold storage method for 'Sulhyang' strawberry mother plants on mother plant growth and the number of runners and daughters

  • Lee, Inha;Kim, Hyun-Sook;Nam, Myeong Hyeon;Oh, Sang-Keun
    • 농업과학연구
    • /
    • 제47권3호
    • /
    • pp.625-632
    • /
    • 2020
  • This test was conducted to determine the appropriate conditions of temperature, storage period, and soil moisture content when using cold storage of potted mother plants of as a means of sufficient dormant breaking and safe overwintering of the strawberry (Fragaria × ananassa Duch. cv. Sulhyang) mother plants. In the treatment by temperature for the dormant breaking of strawberry mother plants, the survival rate of natural overwintering was 91%, whereas the survival rate was 100% at 0, - 2, and - 5℃. As the storage temperature was decreased, the plant height of the mother plants became shorter which tended to decrease after planting. Survival of the mother plants was possible at - 5℃, but after planting, the growth and number of daughter plants decreased significantly. The number of daughter plants was highest at 22.8 per plant at - 2℃ storage. The strawberry mother plants could be stored for up to 8 months in cold storage. However, when the mother plants were stored for a long period, the number of daughter plants was small. When they were stored for 4 months, the growth of the mother plants was vigorous, and the number of runners and daughter plants was high. When the water content of the soil was less than 10 percent (%, w/w) in the cold storage of the pot, the survival rate was 85 percent, which was high due to the dryness. The survival rate was 100 percent at 30 and above, and the growth of the mother plants after planting and the number of daughter plants were high at 30 to 50.

곡물건조저장법 개선을 위한 농가용 Grain Bin에 관한 연구 (Study on the Small Grain Bin for the Improvement of Grain Drying and Storage)

  • 김성래
    • 한국농공학회지
    • /
    • 제16권1호
    • /
    • pp.3263-3291
    • /
    • 1974
  • Experimental work of grain bin was carried out to develop the methods of natural air in-bin drying and storage. The method is considered to be more economical, labour saving, and an effective countermeasure to grain loss. To examine the possibility of farm use of the grain bin and to analyze the related factors concerned with in-bin grain drying and storage, ambient air conditions (especially the change of air temperature and relative humidity) and grain quality during drying and storage periods were investigated. A laboratory model bin was constructed to investigate the effect of different forced air conditions on the drying characteristics of rice. In addition, a grain bin with 2.2m diameter and 1.8m height, considered to be the optimum size for the average Korean farm, was constructed and tested to examine the drying and storing characteristics of rice. The weather data analyzed in this study was the nine-year (from 1964 to 1972) record of air temperature and relative humidity in the Suweon area, and the thirty-year (from 1931 to 1960) record of pentad normal relative humidity and air temperature in the Seoul area. From the results of the weather data analyses, the adequate air delivery hours (which was arbitrary defined as the condition to give less than 75% relative humidity) to dry the rice during October were about nine hours (from approximately 10 A.M. to 7 P.M, ) a day, in which the average air temperature was about 15.9$^{\circ}C$ and average relative humidity was 66%. The occurence of days having three hours of such conditions was 1, 2, and 1-day within the 1st, 2nd add last 10-day periods for the month of October, respectively. Therefore, it may be considered that the weather condition in October was satisfactory for the forced natural air drying. The results of the laboratory model bin test were analyzed to obtain the drying curve and drying rate for different drying stages and grain layers in the bin corresponding to various conditions of forced natural air. A drying experiment with a prototype grain bin showed that an approximate 5 percent grain moisture gradient through a 1.6 meter grain deposit was observed after 80 hours of intermittent drying, giving an over dried zone in the lower grain layers and an extremely high grain moisture zone in the upper layers. This indicates that an effective measure should be taken to reduce this high moisture gradient. In order to investigate the drying characteristics of bulk grain in a layerturning operation a grain bin test was performed. This showed a significant improvement of uniform drying. In this test, approximate 107 hours were required to dry a depth of 1.6 meter of grain from an initial moisture content of 22.2 percent to a moisture content of 16.7 percent using an air delivery rate of 2.8 cubic meter per a minute per every cubic meter of grain. This resulted in a 2 percent moisture gradient from the top to the bottom of the bin. During storage period, till the end of June the average temperature of grain was 2~3$^{\circ}C$ higher than ambient air temperature. But during July when the grain moisture content went up slightly (less than 1 percent), the average temperature of the grain also increased to 3~5$^{\circ}C$ higher than ambient air temperature. It is therefore recommended that for safe grain storage, grain should not be stored in sheet metal bins after mid May. From the above results, in-bin rice drying and storage can be used effectively on Korean farms. It is strongly recommended that the use of grain-bin system should be implemented for farm use to improve farm drying and storage of rice.

  • PDF