• Title/Summary/Keyword: Marine Water Quality

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An experimental study on the injection and spray characteristics of butanol (부탄올의 분사 및 분무특성에 관한 실험적 연구)

  • JEONG, Tak-Su;WANG, Woo-Gyeong;KIM, Sang-Am
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.53 no.1
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    • pp.89-97
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    • 2017
  • Butanol has an ability to improve the ignition quality due to its lower latent heat of vaporization; it has an advantage to reduce a volume of a fuel tank because its energy density is higher than that of ethanol. Also, butanol-diesel oil blending quality is good because butanol has an effect to prevent the phase-separation between two fuels. Even if the blended oil contains water, it can reduce the corrosion of the fuel line. Thus, it is possible to use butanol-diesel oil blended fuel in diesel engine without modification, and it may reduce the environment pollution due to NOx and particulate and the consumption of diesel oil. Therefore, some studies are being advanced whether butanol is adequate as an alternative fuel for diesel engines, and the results of the combustion and exhaust gas emission characteristics are being presented. Though the injection and spray characteristics of butanol are more important in diesel combustion, the has not yet dealt with the matter. In this study, the influence in which differences of physical properties between butanol and diesel oil may affect the injection and spray characteristics such as injection rate, penetration, spray cone angle, spray velocity and process of spray development were examined by using CRDI system, injection rate measuring device and spray visualization system. The results exhibited that the injection and macroscopic spray characteristics of two fuels were nearly the same.

Processings and Quality Characteristics of the Oyster Sauce from IQF Oyster Crassostrea gigas (개체동결 굴(Crassostrea gigas)을 이용한 굴소스의 제조 및 품질특성)

  • Hwang, Young-Suk;Kim, Sang-Hyun;Kim, Byeong-Gyun;Kim, Seon-Geun;Cho, Jun-Hyun;Oh, Kwang-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.6
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    • pp.833-838
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    • 2015
  • To develop a value-added product from individually quick-frozen oyster Crassostrea gigas extract (IQFOE), we prepared two types of oyster sauce (OS): bottled OS (BOS) and retort pouched OS (ROS). We investigated processing conditions, quality metrics and flavor compounds in each type of sauce. We found that the most appropriate base formular for both BOS and ROS consisted of 40.0% IQFOE (Brix $30^{\circ}$), 15.0% sugar, 6.0% salt, 4.0% monosodium glutamate, 4.0% soy sauce, 3.5% starch, 3.0% yeast extract, 3.5% wheat flour and 21.0% water. The crude protein, salinity and amino-nitrogen contents of the BOS and ROS were 8.2 and 8.3%, 9.3 and 9.2%, and 539.2 and 535.2 mg/100 g, respectively. In commercial oyster sauces (COS), these values were 4.7-6.5%, 9.7-12.0%, and 244.7-504.2 mg/100 g, respectively. The total free amino acids content of ROS was 7,346.9 mg/100 g, and the main free amino acids were glutamic acid, taurine, proline, glycine and alanine. The inosinic monophosphate (IMP) content of the ROS was 131.6 mg/100 g, and the primary inorganic ions were Na, K, S and P. The present BOS and ROS have favorable organoleptic qualities and storage stability compared with COS, and are suitable for commercialization as high-flavor seasoning sauces.

Quality Properties of Appenzeller Cheese Added with Fish Surimi (수리미 아펜젤러 치즈의 품질 특성)

  • Choi, Hee-Young;Kim, Kyoung-Hee;Chun, Soon-Sil;Bae, In-Hyu
    • Food Science of Animal Resources
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    • v.31 no.2
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    • pp.232-240
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    • 2011
  • The effects of adding fish surimi to Appenzeller cheese on quality characteristics during ripening were investigated. Cheese samples were prepared with 1.0% surimi. Changes in chemical composition, lactic acid bacterial population, pH, non-casein nitrogen, non-protein nitrogen, water-soluble nitrogen, a consumer sensory evaluation test, chromaticity, texture, and proteolysis were monitored during ripening. The electrophoretic patterns of cheese proteins and the functional components originating from the surimi were investigated. Adding surimi did not affect the appearance or consumer sensory characteristics of the cheeses. Significantly higher amounts of crude fat and moisture were observed in the cheese supplemented with surimi than in cheese without added surimi.

Trends and Prospects of Microalgae used for Food (식품에 이용되는 미세조류와 이를 이용한 식품 연구개발 동향 및 전망)

  • Kwak, Ho Seok;Kim, Ji Soo;Lee, Ja Hyun;Sung, Dong Eun
    • Journal of the Korean Society of Food Culture
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    • v.36 no.1
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    • pp.66-75
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    • 2021
  • Microalgae are unicellular microorganisms inhabiting various ecosystems of the world, including marine and freshwater systems and extreme environments. Only a few species have been actively used as food. Microalgae are attracting attention as a means of biological CO2 reduction because they play an important role in absorbing atmospheric CO2 through their rapid growth by photosynthesis in water. Besides, microalgae are considered to be an eco-friendly energy source because they can rapidly produce biomass containing a large quantum of lipids that can be converted into biodiesel. Several microalgae, such as Chlorella spp., Spirulina spp. and Haematococcus spp. have already been commercialized as functional health supplements because they contain diverse nutrients including proteins, vitamins, minerals, and functional substances such as docosahexaenoic acid (DHA), β-glucan, phycocyanin, astaxanthin, etc. Moreover, they have the potential to be used as food materials that can address the protein-energy malnutrition (PEM) which may occur in the future due to population growth. They can be added to various foods in the form of powder or liquid extract for enhancing the quality characteristics of the foods. In this review, we analyzed several microalgae which can be used as food additives and summarized their characteristics and functions that suggest the possibility of a role for microalgae as future food.

Physicochemical Quality Characteristics of Traditional Kamju Using Extruded Rice Collet Powder (압출 쌀 콜렛 분말을 사용한 전통 감주의 제조 및 이화학적 품질 특성)

  • Je, Hae-Soo;Kang, Kyung-Hun;Park, Si-Young;Choi, Byeong-Dae;Kang, Young-Mi;Kim, Jeong-Gyun
    • Korean Journal of Food Science and Technology
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    • v.48 no.2
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    • pp.147-152
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    • 2016
  • This study was conducted to investigate the physicochemical quality properties and provide basic data for the activation of traditional Kamju of juice type product prepared by mixing malt and extruded rice collet powder. Malt extracts were prepared by extracting the mixture of malt and water at a weight ratio of 25:75 after soaking for 2 h at $45^{\circ}C$. Rice collet powder was prepared by adjusting the barrel temperature to $95^{\circ}C$, screw speed to $3.07{\times}g$, discharge port diameter to 7 mm and a raw material input to 50 kg/h, the powder was then ground to a particle size of 80 mesh. The physicochemical characteristics (pH, color, viscosity, reducing sugars, number of viable cells, free amino acids) and sensory evaluations were conducted at various time points during the saccharification and at different mixing ratios of the extruded rice collet powder to malt extract (5:95, 15:85, 25:75, 35:65, each at $55^{\circ}C$ for 9 h). As a result, with an increase in the proportion of the extruded rice collet powder and saccharification time, the physicochemical properties of traditional Kamju significantly improved (p<0.05). A mixing ratio of 35:65 rice collet powder to malt extract and a saccharification time of 9 h were found to be the most desirable conditions. However, based on the sensory evaluation, a mixing ratio of rice collet powder and malt extract of 25:75 and a saccharification time of 5 h resulted in the most preferable palatability of traditional Kamju (p<0.05). Therefore, the mixing ratio and saccharification time should be determined to provide a better choice with respect to the taste and economic aspects of traditional Kamju.

The Implementation of a Real-time Underwater Acoustic Communication System at Shallow water (천해역에서의 실시간 수중 데이터 통신 시스템 구현)

  • Baek, Hyuk;Park, Jong-Won;Lim, Yong-Kon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.754-757
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    • 2007
  • In this paper, we present an implementation and it's real-sea test of an underwater acoustic data communication system, which allows the system to reduce complexity and increase robustness in time variant underwater environments. For easy adaptation to complicated and time-varying environments of the ocean, all-digital transmitter and receiver systems were implemented. For frame synchronization the CAZAC sequence was used, and QPSK modulation/ demodulation method with carrier frequency of 25kHz and a bandwidth of 5kHz were applied to generate 10kbps transmission rate including overhead. To improve transmission quality, we used several techniques and algorithms such as adaptive beamforming, adaptive equalizer, and convolution coding/Viterbi decoding. for the verification of the system performance, measurement of BER has been done in a very shallow water with depth of 8m at JangMok, Geoje. During the experiment, image data were successfully transmitted up to about 7.4km.

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A Study on Function Assessment of Coastal Wetlands for Ecological Network Establishment -Focused on the Westcoast of Chungnam Province - (생태네트워크 구축을 위한 해안습지 기능평가 연구 - 충남 서해안을 대상으로 -)

  • Park, Mi Ok;Park, Mi Lan;Koo, Bon Hak
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.10 no.6
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    • pp.70-80
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    • 2007
  • This study was surveyed from January to september, 2007 in order to evaluate the function of coastal wetland as a ecological axis in korea peninsula. Assessment was done by RAM (Rapid Assessment Method). RAM is consisted of total 8 contents and divided into high, moderate, low. The preservation grade of RAM is divided into 4 grades; absolute preservation, preservation, improvement and improvement or restoration. Throughout survey on total 14 wetlands of marine, estuary wetland and back marsh which are distributed in west coast in chung-nam province, their function was assessed. As result, total all the 14 wetlands were judged as preservation grade by assessment of 8 functional contents. The function of wetlands assessed as preservation grade showed high in water quality protection and improvement. Also, showed high in vegetation diversity, wildlife habitat and aesthetic recreation. Meanwhile, showed low in ground water recharge, Shoreline/Stream Bank Protection, Flood/Stormwater storage and Flood flow alteration. Of wetlands evaluated as preservation grade, Dae-ho, Sinduri, Bu-Nam lake, Sowhang dune and keum river estuary were assessed as absolute preservative area owing to habitation of international protection species and endangered species. These wetlands are essential to be managed continuously as a area having high ecological value. Farther, this wetlands will be done as a axis of ecological network related to land ecosystem.

Enhancement of the Antioxidant and Anti-inflammatory Activity of Hizikia fusiforme Water Extract by Lactic Acid Bacteria Fermentation (유산균 발효에 의한 톳 (Hizikia fusiforme) 추출액의 항산화 및 항염증 활성 증가)

  • Song, Ho-Su;Eom, Sung-Hwan;Kang, Young-Mi;Choi, Jong-Duck;Kim, Young-Mog
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.2
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    • pp.111-117
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    • 2011
  • We previously reported that fermentation by Lactobacillus brevis LB-20 isolated from Kimchi resulted in improvement of the sensory quality of Hizikia fusiforme water extract. This study was conducted to evaluate the possible application of lactic acid bacteria fermentation to improve the functional qualities of H. fusiforme extract. L. brevis LB-20 was inoculated and cultivated in H. fusiforme extract. The antioxidant and anti-inflammatory activities of extract were then assayed both before and following fermentation for two days. Antioxidant activity was determined by assaying levels of radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, superoxide, and alkyl radical. Lactic acid bacterial fermentation of H. fusiforme extract resulted in enhancement of antioxidant activity. The greatest enhancement of antioxidant activity was seen in the hydroxyl radical scavenging assay that incorporated 0.5 mg/mL of raw and fermented H. fusiforme extract. Fermented extract exhibited greater (21.95%) inhibition of nitric oxide synthesis than did raw extract (14.66%) at a concentration of 1 mg/mL. The fermented extract exerted its potent anti-inflammatory activity via attenuation of expression of inflammation-related cytokine proteins (TNF-${\alpha}$ and iNOS).

A Review of a Bill on the Ocean-Based Climate Solution Act (OBCSA) in the U.S and Implications for the Ocean Climate Change-Related Legal System in Korea (미국 해양기반기후해법 법안(Ocean Based Climate Solution Act, OBCSA)의 검토와 국내 해양기후변화 법제에 대한 시사점)

  • Sora Yun;Moonsuk Lee
    • Ocean and Polar Research
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    • v.45 no.2
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    • pp.71-87
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    • 2023
  • Climate change causes ocean warming, ocean acidification, sea-level rise, dynamic coastal risk, change of ecosystem structure and function, and degradation of ecosystem services. Not only that, but it has negatively impacted the well-being of people, society, and culture, including food security, water resources, water quality, livelihood, health, welfare, infrastructure, transport, tourism, recreation, and so on, especially by particularly degrading indigenous communities and generating an inequitable distribution of benefits and costs. As pointed out here, these adverse impacts of climate change on the ocean have been emphasized at the international and national levels. In contrast, the ocean field has been neglected in the climate change conversation for too long. However, since the UNFCCC COP 25, the ocean has been drawn into the discussion as a solution to address climate change. Moreover, the U.S. Congress recently unveiled a bill called the 'Ocean-Based Climate Solution Act, OBCSA' that reflects the new paradigm of the international regime. The comprehensive legislative bill includes elements related to climate inequity, a blue economy, and a community-led bottom-up policy mechanism, which will have a significant bearing on the ocean-climate legal system. Therefore, this study reviews the OBCSA and deduces implications with regard to the ocean-climate legal system in Korea.

Quality Properties of Fermented Squid Viscera Product with Aspergillus oryzae Koji and Its Seasoning (Koji를 첨가하여 발효한 오징어 내장 조미료의 품질특성)

  • Choi, Seung-Hwa;Kim, Sang-Moo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.1
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    • pp.94-101
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    • 2011
  • Squid (Todarodes pacificus) is processed as dried or seasoned-dried products and its catch gradually increased from 270,298 M/T in 2005 to 367,940 M/T in 2008 in Korea. Squid processing by-product (viscera) was usually discarded as a waste resulting in environmental problem. In order to utilize squid viscera for more value-added products, a natural squid seasoning was developed by fermenting with Aspergillus oryzae koji. Squid viscera at 5, 10 and 15% salt concentrations with fixed levels of 5% koji and 30% water was fermented at room temperature. The quality properties of squid fermented products such as amino-N, TMA, VBN, total viable cell count, pH and total acidity were determined at different fermentation periods. The contents of amino-N, TMA, and VBN of squid seasoning at 5% salt concentration fermented for 14 days were the highest. Based on amino-N content, squid viscera at 5% koji fermented for 14 days was selected for further assays: the content of moisture, crude protein, crude lipid, crude ash, and carbohydrate were 5.98, 35.19, 33.08, 11.30, and 14.45%, respectively. The content of glutamate, alanine, leusine and lysine were 7.06, 12.34, 9.90 and 10.22%, respectively. The $IC_{50}$ values of DPPH scavenging and $\beta$-glucuronidase inhibitory activity were 12.89 and 12.58 mg/mL, respectively. A natural squid seasoning was manufactured by mixing fermented squid viscera and an ingredient. Based on the results of sensory evaluation, the fermented squid viscera seasoning was almost equal to other natural complex seasonings such as anchovy, cow meat, and fisheries seasoning.