• 한국자동차공학회논문집
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• 제21권4호
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• pp.135-143
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• 2013

In this study, we suggested effective countermeasure of biodiesel oxidation problems by investigating the oxidation degradation of biodiesels derived from variable resources and the level of oxidation stability of current distributing biodiesel blended fuels (2%) in Korea, and oxidation stability change according to storage time (for 3 month) and biodiesel blending ratio (2, 5, 7, 10%). By the composition analysis results of biodiesel from various resources which are possible to distribute in Korea, the biodiesel from animal fat has poor oxidation stability and cold performance, while the biodiesel from coconut and palm kernel which are considered as future potential raw material showed good oxidation stability and cold performance. The oxidation stability level of current distributing biodiesel blended fuels in Korea was excellent with showing over 30 hours (average 68 hours) stability, but the oxidation stability of the blended fuel with animal fat biodiesel having poor oxidation property (1.22 hours) was rapidly decreased to below 32 hours by mixing only 2%. Therefore, we have to pay attention to quality control of oxidation property, because the oxidation stability problem can be caused by increasing biodiesel blending ratio and diversifying raw materials those have worse property.

• 동아시아식생활학회지
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• 제18권4호
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• pp.633-640
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• 2008

감귤 부산물 급여가 냉장 중 돼지고기의 품질에 미치는 영향을 검토하였다. 실험에 이용한 돼지고기(195일령, $115{\pm}3Kg$, 여자)는 감귤부산물을 급여하지 않은 T0구, 육성기($73{\sim}153일령$)와 비육기($154{\sim}195일령$)에 각각 3%및 5%급여한 T1구, 그리고 각각 6%와 10% 급여한 T2구로 나누었다. 각각 5 마리의 등심부위를 진공포장하고(Cryovac, $60{\mu}m$, BB4L, Japan) $3^{\circ}C$에서 4주일간 냉장하면서 표면 색도, 저장성, 지방 산패도 및 항산화력에 대하여 실험하였다. 등심육의 pH, 보수력 및 드립 감량은 냉장기간에 관계없이 감귤 부산물 급여에 의해 유의적 차이를 보이지 않았다. 등심육의 휘발성 염기 질소, 일반 세균수 및 TBA 값은 냉장기간에 관계없이 감귤 부산물 급여에 의하여 억제되고 전자공여능 값이 높게 나타났다(p<0.05). 이러한 결과로 감귤 부산물을 급여한 돼지고기는 냉장 중 저장성이 우수하고 지방산패도와 항산화력에 좋은 효과가 있는 것을 알 수 있었다.

• 한국식품영양학회지
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• 제29권6호
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• pp.849-859
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• 2016

Edible insects have gained recognition worldwide as complementary protein sources. Recently, four edible insects were newly allowed to be used as food materials in Korea: the mealworm (Tenebrio molitor), the cricket (Velarifictorus asperses), the white-spotted flower chaffer beetle larva (Protaetia brevitarsis seulensis), and the rhinoceros beetle larva (Allomyrina dichotoma). In this study, we evaluated the oxidative stabilities of these four edible insects during cold storage. The insects were sacrificed by blanching for 3 minutes in boiling water. The blanched insects were then stored at $4^{\circ}C$ in an incubator for 42 days. The color values, titratable acidity, peroxide values, acid values, TBARS, contents of VBN, and total plate counts of the insects were measured at days 0, 2, 4, 7, 10, 14, 21, 28, 35, and 42, respectively. Blanching decreases oxidative stresses during storage. At day 0, the white-spotted flower chaffer beetle larva showed the highest values for acid value, TBARS, VBN, and microbial counts. Most of the oxidative indicators were significantly changed at day 14 in all four insects, possibly related with the growth on all microbial plates. Based on microbial safety and the oxidative stabilities of lipids and proteins, optimal storage conditions for the cricket, the white-spotted flower chaffer beetle larva, and the rhinoceros beetle larva were 10~14 days at $4^{\circ}C$. Likewise, the mealworm showed rapid oxidation after day 14, but poor qualities were not observed until day 28.

• 농업생명과학연구
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• 제53권3호
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• pp.41-49
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• 2019

육제품에 사용되는 합성 항산화제를 대체할 천연물질에 관한 관심이 높아지고 있다. 본 연구는 냉장저장 중 아스타잔틴(AX)의 첨가가 유화형소시지의 산화 안정성 및 품질 특성에 미치는 영향을 조사하기 위해 무첨가구인 대조구, 500 mg/kg BHT (Butylated hydroxytoluene), 및 80 mg/kg AX으로 처리하였다. AX의 첨가는 유화형소시지의 pH, 유화 안정성 및 가열 수율에 유의적인 영향을 미치지 않았다(p>0.05). 그러나 육색의 경우 아스타잔틴 첨가구의 초기(day 1) 색상유지력은 합성 항산화제인 BHT와 동일하였고, 적색도는 높게 나타났다(p<0.05). 항산화 능력에서, 처리구간 단백질 산화는 유의적인 차이가 없었다. 지질 산화의 경우 저장 종료시(day 14) BHT 처리구에서 가장 낮은 값을 나타냈으나 AX 첨가구 또한 무 첨가구인 대조구보다 매우 낮게 나타났다(p<0.05). 한편, 경도는 저장 초기에 비해 저장 종료시 BHT와 AX 처리구들에서 대조구에 비해 낮게 나타났다(p<0.05). 그러므로 천연물질인 아스타잔틴은 기존에 사용되는 합성 항산화제인 BHT를 대체하여 항산화제의 역할뿐만 아니라 육제품의 색상 증진제로도 활용 가능할 것으로 판단된다.

• 한국가금학회지
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• 제16권4호
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• pp.233-238
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• 1989

난황과 난백을 냉동저장 할 경우 발생하는 이화학적 변화를 조사함으로써 계란의 효율적인 저장기법을 확립하고자 실시 한 본 실험의 결과를 요약하면 다음과 같다. 1. 난황액을 냉동저장할 경우 Gel화가 발생하였으며 난백액의 경우 포립성과 포립안전성이 감소하였다. 2. 난자액의 동결저장중 Gel화 방지를 위한 각종 동결방지제(소금, 포도당, 설탕, 각종 amide류) 종에서 소금이 가장 효과적이었다. 3. 난황액과 난백액을 $-5^{\circ}C$와 $-20^{\circ}C$에서 냉동저장할 경우 점도가 증가하였으며 색택의 변화가 일어났는데 난백액의 색택변화는 미약하였다. 4. 난황액에 5% NaCl(소금)을 첨가하여 $-5^{\circ}C$에서 저장하는 방법이 난황의 Gel화를 방지하고 경제적으로 저장할 수 있는 방법이었다. 5. 소금을 첨가하여 냉동저장할 경우 난황액의 유화특성은 다소 감소하였다.

• 한국축산식품학회지
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• 제31권3호
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• pp.339-348
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• 2011

Ground pork containing 0, 1, 2, or 3% rice bran fiber was prepared. pH increased as the amount of rice bran fiber added increased (p<0.05) but decreased during storage. The lightness and redness values of the raw ground pork decreased with the addition of rice bran fiber, and ground pork containing 3% rice bran fiber had the highest yellowness value during early storage (p<0.05). Moreover, adding rice bran fiber was not associated with color stability during storage. Samples containing 2 or 3% rice bran fiber had improved cooking loss, hardness, gumminess, and chewiness. Furthermore, rice bran fiber enhanced tenderness, juiciness, and overall acceptability on a sensory evaluation. These physico-chemical properties were maintained to the final storage period. The best results were obtained with ground pork containing 2 or 3% rice bran fiber. Rice bran fiber combined with useful antioxidants may be a more effective approach to increase the stability of ground pork during cold storage.

• 한국축산식품학회지
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• 제41권4호
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• pp.664-673
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• 2021

This study aimed to investigate the influence of Astragalus membranaceus (AM), Adenophora triphylla (AT), and Ulmus pumila (UP) extracts on the quality traits, palatability, and storage stability of sous-vide (SV) cooked chicken breasts. Chicken breasts were marinated in AM, AT, or UP extracts for 1 h, and then consistently cooked at a constant temperature of 60℃ for 2 h. SV cooked chicken breasts with the UP extract exhibited lower lightness and higher yellowness values on the surface region compared to those with the AM and AT extracts (p<0.05). The control and UP groups displayed a similar overall visual acceptability (p>0.05), although the UP group had lower color acceptability (p<0.01). The UP group also had higher flavor and lower off-flavor intensities compared to the control group (p<0.05), although similar scores were observed in tenderness attributes and juiciness among the groups (p>0.05). Owing to these results regarding overall sensory acceptability, samples from the UP group were more preferred by the trained panelists compared to samples from the control group (p<0.001). On 14 d of cold storage, all the groups with herbal medicinal extracts exhibited a lower concentration of thiobarbituric acid-reactive substances than the control group (p<0.05), and the AT and UP groups showed lower values compared to the AM group due to their higher flavonoid contents (p<0.001). Therefore, meat marination with herbal plant extracts before SV cooking can be effective for enhancing the overall quality of SV cooked chicken breast.

• 한국수산과학회지
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• 제9권2호
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• pp.111-119
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• 1976

Discoloration of canned boiled oyster namely greening, yellowing and browning often occur separately or associatively in the storage of the product. Greening is mainly caused by the appearance of chlorophyll and its derivatives on the surface around the digestive diverticula of the oyster and yellowing by dispersion of carotenoid. Browning reactions by sugar amino condensation or enzymatic action, tyrosinase, also cause an undesirable color development. In this paper, the stability and the changes in distributional or partitional ratio of chlorophyll and carotenoid pigment of meat vs viscera in raw and canned oyster during six month storage in order to measure the dispersion rate of both pigments between meat and viscera, and to evaluate the feasibility of discoloration of oyster meat. The development of brownish pigment and the toss of free tyrosine in oyster were also determined to compare the readiness of color development. In addition the influence of processing and storage conditions to the dispersion rate and the tendency of discoloration, and finally the effect of inhibitor were discussed. The results showed that greening or yellowing was initiated by the dispersion of chlorophyll or carotenoids from viscera to the meat of oyster, and the dispersion rate of carotenoid was much higher than the chlorophyll's, so that, yellowing appeared a leading reaction of discoloration. The dispersion rate was obviously fastened by raising the temperature in the process of sterilization and storage. Consequently, the low temperature storage could largely retard the occurance of yellowing or greening of oyster meat. The pH control of canned oyster did not seem to affect the dispersion of pigment but significantly did on the stability of the piqments. Browning by the reaction of sugar-amino condensation and enzymatic oxidation of tyrosine was positively detected in canned oyster meat. The development of brownish color was influenced rather by the storage temperature than the heating process. Addition of sodium sulfite in can or treating the boiled oyster with sulfite solution prior to filling seemed possibly inhibit the color development particularly in cold-storaged oyster meat.

• 한국도로학회논문집
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• 제19권2호
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• pp.45-53
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• 2017

PURPOSES: The objectives of this study are to develop a new cold-applied crack sealant and to evaluate its properties and field applicability by comparing with other conventionally used crack sealants. METHODS : A new cold-applied crack sealant was developed by using neoprene latex to improve material properties. The fundamental properties such as viscosity, residue %, penetration, and softening point of the developed crack sealant were tested by TxDOT criteria to evaluate crack sealing capability. Moreover, the performance of the developed cold-applied crack sealant was evaluated under both laboratory and field conditions. In the laboratory, the bond property was evaluated using the developed cold-applied crack sealant and conventional hot-applied crack sealant by the bond-properties test standardized under ASTM D 6690. In the field, test sections were constructed on three areas: a trunk road, bus-only lane, and motorway, with the developed crack sealant and three conventional crack sealants. After construction, early field-inspection was performed on the test sections. RESULTS AND CONCLUSIONS : Overall, the developed cold-applied crack sealant demonstrates reasonable storage stability, durability, and bond property compared to conventional hot-applied crack sealants. From the test sections, it was established that the developed cold-applied crack sealant does not pose construction issues. Moreover, the early performance was verified through field inspection. However, as the field inspection was conducted a week after the construction, it is necessary to conduct an inspection of performance from a long-term point of view.

• Preventive Nutrition and Food Science
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• 제12권4호
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• pp.242-250
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• 2007

This study evaluated the storage stability of a variety of sauce products in the Korean market, determined primary quality indices for three typical products, and proposed functional relationships that are useful for determining shelf life at different temperatures. Most of the products examined were found to combine hurdles of low pH, low water activity, and the use of heat processing as methods for producing the required storage stability while maintaining the sensory quality of the products. For a meat extract solution produced for cold noodles (pH=4.3; $a_w=0.98$), the primary quality change determining shelf life was lipid oxidation, determined here by the TBA value. The primary quality index of a soybean paste seasoning mix (pH=4.0; $a_w=0.78$), which had a microbial load of 2.8 log (CFU/g), was a decrease in its pH. The primary quality index for a sandwich spread (pH=4.0; $a_w=0.88$) was changes in its surface color. The temperature dependence of changes in the primary quality indices can be described by the Arrhenius equation, which can estimate the shelf life at any arbitrary limit as a function of temperature. The activation energies for changes in the primary quality indices of the meat extract solution, the soybean paste seasoning, and the sandwich spread were 20.3, 27.2, and 43.5 kJ/mol, respectively.