• 한국축산식품학회지
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• 제37권4호
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• pp.571-578
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• 2017

This study aimed to determine the optimal ratio of natural calcium powders (oyster shell and egg shell calcium) as synthetic phosphate replacers in pork products. Ground pork samples were subjected to six treatments, as follows: control (-) (no phosphate added), control (+) (0.3% phosphate blend added), treatment 1 (0.5% oyster shell calcium powder added), treatment 2 (0.3% oyster shell calcium powder and 0.2% egg shell calcium powder added), treatment 3 (0.2% oyster shell calcium powder and 0.3% egg shell calcium powder added), and treatment 4 (0.5% egg shell calcium powder added). The addition of natural calcium powders resulted in an increase in the pH values of meat products, regardless of whether they were used individually or mixed. The highest cooking loss was observed (p<0.05) in the negative control samples, whereas the cooking loss in samples with natural calcium powder added was similar (p>0.05) to that in the positive control samples. CIE $L^*$ values decreased as the amount of added egg shell calcium powder increased. CIE $a^*$ values were higher (p<0.05) in samples containing natural calcium powder (treatments 1, 2, 3, and 4) than in the positive control. The combination of oyster shell calcium powder and egg shell powder (treatment 2 or 3) was effective for the improvement of textural properties of the pork products. The findings show that the combined use of 0.2% oyster shell calcium and 0.3% egg shell calcium should enable the replacement of synthetic phosphate in the production of cooked pork products with desirable qualities.

• 한국농공학회지
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• 제42권2호
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• pp.93-98
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• 2000

This study is performed to evalute experimentally the nondestructive properties on the concrete that is treated with crushed oyster shell powder of 0.15m or smaller in diameter. The ultrsonic pulse velocity of crushed oyster shell concrete(COSC) is in the range of 4.110-4.267m/s, and the dynamic modulus of elasticity of COSC range from 288$\times$10$^3$ to 318 $\times$10$^3$kgf/$\textrm{cm}^2$. The ultrasonic pulse velocity and dynamic modulus of elasticity are similar to those of normal portland cement concrete. The highest ultrasonic pulse velocity and dynamic modulus of COSC are measured at the 2.5% addition rate by weight of crushed oyster shell powder. The acid-resistance in increased of the content of crushed oyster shell powder. The acid-resistance of COSC with 15% addition rate by weight of crushed oyster shell power is 1.6 times greater than that of normal portland cement concrete. It is concluded that the addition of crushed oyster shell powder to normal portland cement concrete contributed to improve the nondestructive properties of concrete.

• 한국식품조리과학회지
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• 제26권2호
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• pp.188-197
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• 2010

In this study, the quality characteristics and storage properties of gat kimchi added with oyster shell powder and Salicornia herbacea powder were investigated during a storage time of 80 days at $5^{\circ}C$. After storage for 80 days, the average calcium contents were significantly higher in the kimchi containing the oyster shell powder and Salicornia herbacea powder than the control. In addition, the average hardness value was significantly higher in the OS4 group(oyster shell powder at 4% and Salicornia herbacea powder at 2%) than the control group, as well as the OS10 group(oyster shell powder at 10% and Salicornia herbacea powder at 2%) during storage for 80 days. The hunter b value of the OS4 group was significantly lower than the control group. During fermentation, gat kimchi containing the oyster shell powder and Salicornia herbacea powder had a higher pH and a lower acidity value than the control group. In terms of sensory evaluation, there were no significant differences between the control and calcium-added kimchi during fermentation. After 40 days of storage, the OS4 group showed a lower total viable count, as well as lower lactic acid bacteria, yeast and E. coli, as compared with the control and OS10 groups. Based on the microbial load, the gat kimchi containing the oyster shell powder showed limitations in terms of shelf life.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.33-34
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• 2022

The purpose of this study was to provide basic data for applying oyster shells and egg shells as fireproof cladding materials by substituting fine aggregates for oyster shell powder and egg shell powder, and comparing strength and fire resistance performance. The reason for the high strength was thought to be that the oyster shell had higher strength than the egg shell itself, and both ESP and OSP were measured at a backside temperature of less than 500℃, so it was judged that it could be used as a fireproof coating for steel structures.

• 한국분말재료학회지
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• 제23권3호
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• pp.221-227
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• 2016

Waste oyster shells create several serious problems; however, only some parts of them are being utilized currently. The ideal solution would be to convert the waste shells into a product that is both environmentally beneficial and economically viable. An experimental study is carried out to investigate the recycling possibilities for oyster shell waste. Bulk ceramic bodies are produced from the oyster shell powder in three sequential processes. First, the shell powder is calcined to form calcium oxide CaO, which is then slaked by a slaking reaction with water to produce calcium hydroxide $Ca(OH)_2$. Then, calcium hydroxide powder is formed by uniaxial pressing. Finally, the calcium hydroxide compact is reconverted to calcium carbonate via a carbonation reaction with carbon dioxide released from the shell powder bed during firing at $550^{\circ}C$. The bulk body obtained from waste oyster shells could be utilized as a marine structural porous material.

• 한국축산식품학회지
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• 제44권4호
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• pp.849-860
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• 2024

The use of natural ingredients in meat processing has recently gained considerable interest, as consumers are increasingly attracted to clean-label meat products. However, limited research has been conducted on the use of natural substitutes for synthetic phosphates in the production of clean-label meat products. Therefore, this study aimed to explore the potential of oyster shell powder as a substitute for synthetic phosphates in pork patties cured with Chinese cabbage or radish powders. Four different groups of patties were prepared using a combination of 0.3% or 0.6% oyster shell powder and 0.4% Chinese cabbage or radish powder, respectively. These were compared with a positive control group that contained added nitrite, phosphate, and ascorbate and a negative control group without these synthetic ingredients. The results showed that patties treated with oyster shell powder had lower (p<0.05) cooking loss, thickness and diameter shrinkage, and lipid oxidation than the negative control but had lower (p<0.05) residual nitrite content and curing efficiency than the positive control. However, the use of 0.6% oyster shell powder adversely affected the curing process, resulting in a decreased curing efficiency. The impact of the vegetable powder types tested in this study on the quality attributes of the cured pork patties was negligible. Consequently, this study suggests that 0.3% oyster shell powder could serve as a suitable replacement for synthetic phosphate in pork patties cured with Chinese cabbage or radish powders. Further research on the microbiological safety and sensory evaluation of clean-label patties during storage is required for practical applications.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.94-95
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• 2020

Oyster shells are characterized by coarse and coarse grains, but similar in strength to sand, and egg shells are fine grains but weak in strength. In terms of supply and demand of raw materials, oyster shells can be supplied only in limited periods and regions in winter and south coast of the year, but egg shells have the advantage of being able to supply and supply nationwide 365 days. This study aims to study the change in strength characteristics by mixing oyster shell powder and egg shell powder with the same particle size and mixing up to 150%. The conclusions of the flexural and compressive strength tests of mortar mixed with oyster shell powder and egg shell powder are as follows. The 7-day flexural and compressive strength with ESP added and the 3-day flexural and compressive strength with OSP added were similar, which is thought to be because the strength of OSP is higher than that of ESP.

• 한국토양비료학회지
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• 제37권6호
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• pp.383-387
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• 2004

농가에서 관리하는 9년생 후지품종의 사과 과수원에 패화석과 석회고토의 중화량를 시용하여 작물생육과 토양 화학성 변화를 조사한 결과는 다음과 같았다. 석회를 시용하지 않은 처리구의 토양은 시험전후 pH가 5.6으로 차이가 없었으나, 패화석과 석회고토 처리구에서는 Ca, Mg 함량이 증가되고 pH가 5.6에서 6.8로 높아져 패화석은 석회고토 처리구와 동등의 산도교정 효과가 있었다. 패화석과 석회고토 시용으로 사과나무 신초의 초장과 신초수, 신초경이 증가되었으며, 석회 무시용에 비해 간경과 주지경의 직경이 연간 0.7 및 1.0 mm 증가하였고, 부주지경의 증가는 패화석과 석회고토 시용이 각각 1.7 및 1.8 mm 증가하여 사과나무의 생육에 효과가 있는 것으로 나타났다. 패화석과 석회고토 처리로 시기별 엽록소함량은 차이가 없었으나 건물중 변화는 10월 23일 조사시 무시용27.3% 대비 패화석과 석회고토 시용이 각각 33.1 및 31.0%로서 높았다. 시기별 엽중 무기성분으로 질소함량은 무시용 대비 패화석과 석회고토 시용으로 함량이 증가하였으며, CaO 함량은 큰 차이가 없었고, Mn 함량이 높았다. 사과의 당도, 경도 및 산도에 대한 패화석 시용효과는 무처리와 비교해 차이가 나타나지 않았으며, 석회고토 처리시 경도는 석회 무시용에 비해 낮았다. 패화석 시용시 색도는 황색도가 약간 높았으나 적색도에서는 낮았으며, 선명도는 처리간 차이가 나타나지 않아 패화석 시용이 사과의 품질 향상에는 영향을 미치지 못하였고 수량은 $37,000kg\;ha^{-1}$로 무시용 대비 5% 증수되었다.

• 한국환경보건학회지
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• 제26권2호
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• pp.30-33
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• 2000

The objective of this study is to examine the subsitiution effect of the waste oyster shell powder as the conditioning agent in municipal wasterwater sludge dewatering process. Beacuse the oyster shells have a large amount(about 38% by weight) of alkaline minerals, such as calcium and magnesium, they are thought to have the potential as a good conditioning agent. In this study, the physico-chemical properties of powdered oyster shells (75${\mu}{\textrm}{m}$ or 200 mesh) and the dewatering characteristics of municipal waste water sludge using powdered oyster shells and CaCO3 are investigated. The conclusions are as follows, 1. Oyster shell could produce calcium ions up to 14ppm at pH-7.0, and this represents that oyster shell is a potential properties as a good conditioner. 2. 100ml of wastewater sludges, conditioned with pretreated oyster shell, are dewatered to the level of 25% solid concentration. 3. Wasterwater sludges, conditioned with oyster shell and CaCO3 are dewatered to the level of 32% solid concentration. And this shows that two-stage combined conditioning process is desirable than the one-stage conditioning process.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.135-136
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• 2017

Oyster shell is produce by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and the strength characteristic of it is similar to send. So we produced mortar test piece using grounded oyster shell powder according to Filler and reviewed Fireproof Performance.