• Title/Summary/Keyword: 균일 가열

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Antioxidant Activities of Seasoning Sauces Prepared with Geranium thunbergii sieb. et Zucc. and Crataegi fructus and the Quality Changes of Seasoned Pork during Storage (산사와 현초를 이용한 돈육불고기양념의 항산화 활성과 이로 제조한 양념돈육의 품질특성)

  • Lee, Shin-Ho;Jeong, Eun-Ju;Jung, Tae-Sung;Park, La-Young
    • Korean Journal of Food Science and Technology
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    • v.41 no.1
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    • pp.57-63
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    • 2009
  • In this study, seasoning sauces were prepared with Geranium thunbergii sieb. et Zucc. (1%, PGT), Crataegi fructus (1%, PCF) and their combination (0.5% PGT + 0.5% PCF, bPMGC) and then the quality characteristics of the sauces and seasoned pork were investigated. The lightness, redness and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of the sauces were increased by the addition of Crataegi fructus. Sensory qualities such as taste, color and overall acceptability were scored higher in the sauce prepared with Crataegi fructus than the control. The viable cell counts of pork seasoned with the various sauces were 5.04 CFU/g (control), 4.59 CFU/g (PGT), 3.88 CFU/g (PCF) and 4.38 CFU/g (PMGC) after storage for 15 days at $4^{\circ}C$, respectively. The coliform count of the control pork was below 1.0 CFU/g after storage for 25 days and coliform were not detected in PGT, PCF and PMGC after storage for 10 days at $4^{\circ}C$. The thiobarbitunc acid reaotive substance values of PGT, PCF and PMGC were significantly lower than that of control, but volatile basic nitrogen contents were not significantly different between the treated and untreated pork samples during storage. Cooking loss increased in all treatments during storage for 25 days and their water holding capacity increased during storage for 10 days and decreased thereafter. The lightness, redness and yellowness values of PCF were higher than those of the control. The sensory qualities of PCF, including taste, color and overall acceptability, were significantly improved compared to the control. Finally, the pork seasoned with the sauce containing 1% Crataegi fructus extract had significantly improved shelflife, water holding capacity, inhibition of rancidity, color and sensory quality.

Characterization of Low-Temperature Pyrolysis and Separation of Cr, Cu and As Compounds of CCA-treated Wood (CCA (Chromated Copper Arsenate) 처리 목재의 저온 열분해와 CCA 유효 성분분리 특성)

  • Lim, Kie-Pyo;Lee, Jong-Tak;Bum, Jung-Won
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.1
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    • pp.73-80
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    • 2007
  • This study was carried out to separate the heavy toxic metals in eco-building materials by low-temperature pyrolysis, especially arsenic (As) compounds in CCA wood preservative as a solid in char. The pyrolysis was carried out to heat the CCA-treated Hemlock at $280^{\circ}C$, $300^{\circ}C$, $320^{\circ}C$, and $340^{\circ}C$ for 60 mins. Laboratory scale pyrolyzer composed of [preheater$\rightarrow$pyrolyzer$\rightarrow$1st water scrubber$\rightarrow$2nd bubbling flask with 1% $HNO_3$ solution$\rightarrow$vent], and was operated to absorb the volatile metal compound particulates at the primary water scrubber and the secondary nitric acid bubbling flask with cooling condenser of $4^{\circ}C$ under nitrogen stream of 20 mL/min flow rate. And the contents of copper, chromium and arsenic compounds in its pyrolysis such as carbonized CCA treated wood, 1st washing and 2nd washing liquors as well as its raw materials, were determined using ICP-AES. The results are as follows : 1. The yield of char in low-temperature pyrolysis reached about 50 percentage similar to the result of common pyrolytic process. 2. The higher the pyrolytic temperature was, the more the volatiles of CCA, and in particular, the arsenic compounds were to be further more volatile above $320^{\circ}C$, even though the more repetitive and sequential monitorings were necessary. 3. More than 85 percentage of CCA in CCA-treated wood was left in char in such low-temperature pyrolytic condition at $300^{\circ}C$. 4. Washing system for absorption of volatile CCA in this experiment required much more contacting time between volatile gases and water to prevent the loss of CCA compounds, especially the loss of arsenic compound. 5. Therefore, more complete recovery of CCA components in CCA-treated wood required the lower temperature than $320^{\circ}C$, and the longer contacting time of volatile gases and water needed the special washing and recovery system to separate the toxic and volatile arsenic compounds in vent gases.

Temporal and spatial distributions of heat fluxes in the East Sea(Sea of Japan) (東海熱收支 의 時.空間的인 分布)

  • 박원선;오임상
    • 한국해양학회지
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    • v.30 no.2
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    • pp.91-115
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    • 1995
  • Air-sea heat fluxes in the East Sea were estimated from the various ship's data observed from 1961 to 1990 and the JMA buoy #6 data from 1976 to 1985. The oceanic heat transport in the sea was also determined from the fluxes above and the heat storage rate of the upper layer of 200m from the sea surface. In winter, The incoming solar radiation is almost balanced with the outgoing longwave radiation. but the sea loses her heat through the sea surface mainly due to the latent and sensible heat fluxes. The spatial variation of the net surface heat flux is about 100 Wm/SUP -2/, and the maximum loss of heat is occurred near the Tsugaru Strait. There are also lots of heat losses in the southern part of the East Sea, Korea Strait and Ulleung Basin. Particularly, the heat strong loss in the south-western part of the sea might be concerned with the formation of her Intermediate Homogeneous Water. In summer, the sea is heated up to about 120∼140 Wm/SUP -2/ sue to strong incoming solar radiation and weak turbulent heat fluxes and her spatial variation is only about 20 Wm/SUP -2/. The oceanic heat flux is positive in the southeasten part f the sea and the magnitude of the flux is larger than that of the net surface heat flux. This shows the importance of the area. In the southwestern part of the sea, however, the oceanic heat flux is negative. This fact implies cold water inflow, the North Korean Cold Water. The sigh of net surface heat flux is changed from negative to positive in March and from positive to negative in September. The heat content in the upper surface 200 m from the sea surface reaches its minimum in March and maximum in October. The annual variation of the net surface heat flux is 580 Wm/SUP -2/ in southwestern part of the sea. The annual mean values of net surface heat fluxes are negative, which mean the net heat transfer from the sea to the atmosphere. The magnitude of the flux is about 130 Wm/SUP -2/ near the Tsugaru Strait. The net surface fluxes in the Korea Strait and the Ulleung Basin are relatively larger than those of the rest areas. The spatial mean values of surface heat fluxes from 35$^{\circ}C$ to 39$^{\circ}$N are 129, -90, -58, and -32 Wm/SUP -2/ for the incoming solar radiation, latent hear flux, outgoing longwave radiation, and sensible heat flux, respectively.

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Prevalence of Microbiological Contamination in the Ready-To-Eat Side Dishes Sold in Gyeongsangnam-do, South Korea (경남지역에서 유통되는 즉석 반찬류의 미생물 오염도 조사)

  • Ji-Yeon Um;Hye-Jeong Jang;Yeon-Ju Choi;So-Young Kim;Areum Jo;Min Young Kim;Jihee Ahn;Jea-Dong Kim
    • Journal of Food Hygiene and Safety
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    • v.38 no.4
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    • pp.217-227
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    • 2023
  • The consumption of ready-to-eat side dishes is rapidly growing in South Korea. These foods are particularly vulnerable to microbiological contamination as they are often cooked without any treatment, such as heating or stored at room temperature after cooking. Hence, in 2022, we analyzed the ready-to-eat side dishes sold in Gyeongsangnam-do, South Korea for microbiological contamination. We collected 100 samples from supermarkets in 7 cities, and then examined them for presence of food-borne pathogens and sanitary indicator bacteria. In the analysis of the food-borne pathogens, Bacillus cereus and Clostridium perfringens were isolated from 51 samples (51.0%) and 3 samples (3.0%), respectively. However, both quantitatively met the Korean Food Standards Codex. Genes of five different enterotoxins and one emetic toxin were analyzed from the 51 isolated B. cereus strains. We detected enterotoxin entFM (100.0%), nheA (94.1%), hblC (58.8%), cytK (56.9%), and bceT (41.2%) in 51 isolates, and emetic toxin gene, CER, in only one (2.0%) isolate. We did not detect C. perfringens toxin gene (cpe) that causes food poisoning in any one of the three C. perfringens isolates. In the case of sanitary indicator bacteria, Kimchi had the highest levels of total aerobic bacteria and coliforms, followed by Saengchae, Jeotgal, Jeolim, Namul, and Jorim, respectively. We counted total aerobic bacteria at two different storage temperatures (4℃ and 20℃) to determine the effect of storage temperature. When stored at 20℃, total aerobic bacteria count increased in most of the ready-to-eat side dishes, except for Jeotgal. This result conclusively shows the need for refrigerating the ready-to-eat side dishes after purchase. Further research is needed to assess the risk and safety of the ready-to-eat side dishes available in the market and determine appropriate safety management practices.

Current Status and Perspectives in Varietal Improvement of Rice Cultivars for High-Quality and Value-Added Products (쌀 품질 고급화 및 고부가가치화를 위한 육종현황과 전망)

  • 최해춘
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47
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    • pp.15-32
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    • 2002
  • The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s-1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great progress and success was obtained in development of high-quality japonica cultivars and quality evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice cultivars and special rices adaptable for food processing such as large kernel, chalky endosperm, aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer, Recently, new special rices such as extremely low-amylose dull or opaque non-glutinous endosperm mutants were developed. Also, a high-lysine rice variety was developed for higher nutritional utility. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and texture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak, hot paste and consistency viscosities of viscosities with year difference. The high-quality rice variety "IIpumbyeo" showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic microscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high probability of determination. The $\alpha$-amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were IIpumbyeo, Chucheongyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tonsil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice breed. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large grain rices showed better suitability far fermentation and brewing. The glutinous rice were classified into nine different varietal groups based on various physicochemical and structural characteristics of endosperm. There was some close associations among these grain properties and large varietal difference in suitability to various traditional food processing. Our breeding efforts on improvement of rice quality for high palatability and processing utility or value-adding products in the future should focus on not only continuous enhancement of marketing and eating qualities but also the diversification in morphological, physicochemical and nutritional characteristics of rice grain suitable for processing various value-added rice foods.ice foods.