Because the pig is a valuable candidate for a preclinical model of human cell therapy as well as an important food source, understanding a physiology of pig myogenic progenitors such as skeletal muscle satellite cells and myoblasts is required for cure of muscular diseases and improvement of meat production. For these reasons, we tried to isolate and culture the pig progenitor cells from skeletal muscle. Pig satellite cells, known as muscle stem cells, were isolated from biceps femoris of neonatal pigs by enzymatic digestion method. Muscle satellite cells are quiescent in uninjured muscle. Upon injury, they are activated into proliferating state, known as myoblasts, by growth factors and, in turn, differentiated forward to myocytes and myotubes. To trigger proliferation in vitro, the isolated satellite cells were cultured with epidermal growth factor (EGF) and dexamethasone (BMP4 inhibitor). As a result, the pig satellite cells were efficiently converted into proliferating myoblasts and stably maintained over an extended period. The myoblasts were confirmed by markers of PAX7, MYF5, and MYOD1. Our finding showed that modulating EGF and BMP4 signaling are essential for maintaining muscle stem cells. This culture method could be applied for a production of cultured meat and further basic research of muscle development. This work was supported by the Korea Institute of Planning and Evaluation for Technology in food, agriculture, forestry, and fisheries (IPET) through the Development of High Value-Added Food Technology Program funded by the Ministry of Agriculture, Food, and Rural Affairs (MAFRA; 118042-03-1-HD020).

In this study, using the surface dielectric barrier discharge (DBD) produced at atmospheric pressure to improve the physiological activities of quercetin was investigated. Quercetin (at 200 ppm) was treated using air DBD with an input power of 250 W. The tyrosinase inhibition effect and total phenolic content of quercetin increased from 38.96 to 91.58% and from 134.53 to 152.93 ppm, respectively, after 20 min of plasma treatment. The antioxidant activity of quercetin treated for 20 min in the lipid models was higher than that of quercetin treated for 0, 5, and 10 min. Furthermore, plasma-treated quercetin exhibited antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, and Staphylococcus aureus, whereas activity was not shown in the control. Structural modifications of the quercetin molecule induced by plasma might be responsible for the improvements in its physiological activity. These results indicate that DBD plasma could be used to enhance the physiological activity of quercetin for various applications in food.

국내 시판 중인 선식의 유통 안전성 확보를 위한 기초기반연구로 대기압 플라즈마 처리한 선식의 품질 특성 평가를 진행하였다. 본 연구에서 이용한 플라즈마는 컨테이너형 유전격벽 플라즈마로 방전 가스는 공기를 활용하여 0, 5, 10 및 20분 처리하였고 미생물 감균효과, 색도, pH관능평가를 진행하였다. 일반 호기성 미생물 분석 결과 20분 처리 시 약 1.70 log CFU/g 감소하였으며 B. cereus, B. subtilis 및 E. coli O157:H7을 이용한 접종 시험 결과 각각 2.20, 2.22 및 2.50 log CFU/g 감소하였다. 색도 측정결과 플라즈마 처리에 의해 명도 값은 증가하였으나 적색도 및 황색도는 감소하였다. 플라즈마 처리에 의한 선식의 pH측정 결과 처리시간에 따라 감소하는 경향을 보였다. 하지만 플라즈마 처리에 의해 단백질 지질산화가 일어나 관능 품질이 저하되는 경향을 보였다. 따라서 공기로 방전된 대기압 플라즈마 기술은 선식의 품질안전성을 개선할 수 있으나, 관능적 품질 특성 개선을 위한 후속연구가 필요하다고 판단된다.

We developed a type of sausage made of chicken breast and liquid egg whites for consumers interested in weight management. To determine the quality of the product, its chemical characteristics, fatty acid composition, free amino acid contents, and nucleotides contents were evaluated during 4 weeks of storage. Sensory evaluation was conducted by both general consumers and body-builders. The sausage was proposed as a fat-free product as fat content was 0.12% based on the Korean Indication Standard of Animal Origin Food. Protein content was 13.42% and calorie value was 61.50 kcal/100 g of the sausage. In sensory evaluation, the mixture of chicken breast and egg whites stuffed into the same casing had an adverse effect on taste, color, texture and overall acceptance while the product that contained egg white stuffed separately into the outer casing enclosing the chicken breast (double layer) improved these attributes. The developed double-layer sausage can last for at least 4 weeks of storage without quality deterioration of flavor-related compounds, such as fatty acids and nucleotides.

The influence of aging on the flavor precursors and volatile compounds of top round beef was studied. The concentrations of free amino acids, nucleotides, creatine, dipeptides, and volatile compounds were measured after top round from Hanwoo was aged at 4℃ for 21 days. The amount of free amino acids in top round significantly increased with the increase of aging period. There was no effect of aging on the concentrations of adenosine monophosphate or inosine in top round. The inosine monophosphate content of top round significantly decreased with age, while the hypoxanthine content increased. The concentrations of creatine, carnosine, and anserine in top round were not influenced by aging. In total, 24 volatile compound were identified in aged, cooked top round. Of these, the quantities of aldehydes (propanal, pentanal, hexanal, heptanal, octanal, and nonanal), hydrocarbons (pentane and octane), 2-butanone, ethyl acetate, and pyridines (4-ethynyl-pyridine and 4-acetyl-pyridine) significantly increased after aging. We conclude that the flavor of top round can be improved by aging.

This study investigated the quality change of strip loin from hanwoo with quality grade 2 produced by dry aging, and compared the quality of dry-aged strip loin with that of strip loin from hanwoo with quality grade 1+. Hanwoo strip loins with quality grade 1+ (SL1) and 2 (SL2) after a day of slaughter and dry-aged strip loin (DSL2) aged for 21 days at 2℃ with 85% humidity were obtained from local markets. The proximate composition, pH, cooking loss, lipid oxidation, instrumental color (CIE L*, a* and b* value) and sensory properties of the strip loins were measured. DSL2 contained low moisture and high protein contents compared with SL2, and low fat, high protein, and high ash contents compared with SL1 (p<0.05). The pH and cooking loss were higher and lower, respectively, in DSL2 compared to SL2 (p<0.05). SL1 had a higher pH than DSL2 (p<0.05). However, the cooking loss was not different between SL1 and DSL2. The TBARS value was the highest in DSL2 and the lowest in SL2 (p<0.05). DSL2 had higher L* and b* value compared with SL2 (p<0.05). There were no significant differences of L*, a* and b* values between DSL2 and SL1. Sensory properties such as the color, flavor, taste, texture, and acceptability of DSL2 were higher than those of SL2 (p<0.05). There was no significant different in all sensory properties between DSL2 and SL1. According to the results, dry aging can improve the nutritional and sensorial quality of strip loin with quality grade 2 to quality comparable to quality grade 1+.

본 연구는 양념 닭 가슴살의 양념 액에 귤 껍질 추출물(CPE, 2%), 양파 껍질 추출물(OPE, 2%), calcium lactate(2%), 난황 유래 phosvitin(0.1%)과 CPE, OPE 및 calcium lactate 복합처리를 첨가하였을 때 서로 다른 저장온도와 저장기간에 따른 항균 효과 및 품질 변화를 확인하고자 수행되었다. 모든 저장온도와 저장기간에서 CPE, OPE 및 복합 처리군의 총 호기성 세균 수는 대조구에 비해 유의적으로 낮게 확인되었으며, 가장 높은 미생물 생장 억제 효과가 있었던 처리군은 CPE 처리군이었다. 하지만, calcium lactate와 phosvitin 처리군의 미생물의 성장 억제 효과는 나타나지 않았다. pH의 경우, calcium lactate와 OPE 처리군은 모든 저장온도의 저장 0일차에서 대조구에 비해 유의적으로 낮은 값을 나타내었다. OPE 처리군은 모든 저장온도와 저장기간에서 다른 처리구들에 비해 유의적으로 높은 적색도를 나타내었고, CPE와 함께 저장온도에 따른 유의적 차이를 나타내지 않았다. 하지만 이러한 OPE 처리군은 풍미, 맛 및 종합적 기호도에서 다른 처리구들에 비해 유의적으로 낮은 값을 보였으며, calcium lactate와 phosvitin 처리군의 종합적 기호도는 대조구와 유의적 차이가 나타나지 않았다. 결론적으로, 양념 닭가슴살의 CPE, OPE 및 복합처리군에서 저장온도를 달리한 저장기간에 따른 미생물 억제 효과를 확인할 수 있었으나, 관능적 특성을 개선하는 방법의 개발이 필요하다고 판단된다.

근내지방도(IMF)가 한우육의 품질 및 기능성분에 미치는 영향을 조사하기 위하여, 250두의 한우를 근내지방 함량 에 따라 Low(<14%, n=96), Medium(14～17%, n=83), High(>17%; n=71) 세 그룹으로 분류하고, 7일간 숙성 후 등심육의 품질 및 기능성분을 분석하였다. 한우 등심육의 수분 함량은 IMF와 반비례하였으며, High IMF 그룹은 Low IMP 그룹 에 비하여 낮은 드립 감량을 나타내었다. 기능성 didpeptide 함량은 IMF에 따라 유의적 차이가 없었으나, High IMF 그룹은 다른 그룹보다 낮은 inosine monophosphate, 높은 hypoxanthine, 낮은 histidine 함량은 나타내었다. 불포화지방산 의 비율은 IMF에 따라 유의적 차이가 없었다. 저지방육의 건강지향적 가치를 고려할 때 지나친 IMF를 목표로 하는 육종 및 사양은 지양되어야 할 것으로 판단되었다.

This study was carried out to evaluate the genotoxicity of the gamma-irradiated (0, 5 and 10 kGy) milk and ice cream. The Salmonella typhimurium reversion assay was performed using S. typhimurium TA98, TA100, TA102, TA1535 and TA1537 as tester strains. The number of revertant colonies were not increased in both milk and ice cream, compared with negative controls with or without metabolic activation. There were no significant differences among the irradiation doses. These results indicate that the gamma-irradiated milk and ice cream do not show any genotoxic effect under these experimental conditions, and that they may be safe genotoxically.

국내에서 생산되는 벼의 저장안전성 확보를 위한 기초기 반연구로 플라즈마 기술을 이용하여 벼의 저장기간 및 온도에 따른 미생물 생육 및 성분 변화를 관찰하였다. 플라즈마 시스템은 컨테이너형 유전격벽 플라즈마로 공기방전방식을 이용하여 삼광, 청품, 미소미, 팔방미 품종을 0, 10 및 20분간 처리하여 4℃, 25℃에서 2달간 저장하여 실험하였 다. 미생물 생육 변화를 관찰한 결과 저장 초기에는 일반호기성 미생물은 3.46-3.86 log CFU/g, 곰팡이는 2.27-2.86 log CFU/g이 검출되었다. 저장온도 및 기간에 따라 일반호기성 미생물 및 곰팡이의 생육은 증가하였으며, 품종간의 큰 차이는 없었다. 저장한 후의 미생물 분석 결과 플라즈마 처리 군의 미생물이 약 1.50 log CFU/g 적게 생육되었다. 플라즈마 처리한 벼의 수분함량을 측정한 결과 플라즈마 처리에 의한 큰 차이는 관찰되지 않았으나, 저장온도가 올라가면 수분함량이 감소하는 것을 확인하였다. 지방은 플라즈마에 의해 감소하는 경향을 보였으나, 단백질 함량은 플라즈마 및 저장조건에 따른 일관적인 변화는 관찰되지 않았다. 아밀로스 함량의 경우 삼광, 청품, 미소미 품종은 플라즈마에 의한 함량 변화는 관찰되지 않았으나 팔방미는 증가하는 경향을 보였다. 이상의 결과를 종합하여 볼 때 플라즈마에 의해 벼의 저장안전성을 개선할 수 있으며 품질 변화의 최소화를 위하여 저온저장이 효과적이라고 판단된다.

This study was conducted to investigate the reliability of automatic cracked and bloody egg detector according to the age of the hens and the level of the detector. The results of this study are expected to be helpful in the implementation of the Korean egg grading system, which is expected to improve egg quality for consumers. An official egg grader randomly selected 1,000 eggs for each experiment (total 36,000 eggs), ran them through the automatic detector, and conducted labor inspection using the eggs that were classified by the detector as cracked, bloody, and normal eggs. The results showed that more cracked eggs were laid by hens aged 40-60 weeks than by hens aged 30 weeks (p<0.05). Also, when the detector level increased from four to seven (i.e., when it became less sensitive), its cracked eggs detection rate dropped, and the total rate of cracked eggs was consistent after the labor inspection of the classified eggs. The automatic detector achieved over 97 percent accuracy. The bloody eggs constituted only 0.005 percent of all the samples, and all the detector-detected eggs were bloody eggs after the labor inspection of both the bloody and normal egg lines. Therefore, it can be concluded that the automatic cracked and bloody egg detector was reliable and can be used in the egg grading system. Considering that cracked eggs should be less than 9 percent of first-grade eggs in the present egg grading system, the use of an automatic crack detector may help provide better-quality eggs to consumers by producing less than 5.5 percent cracked eggs.

This study was conducted to evaluate the changes in the quality of rice wine (Makgeolli) treated with UV-C and electron beam (EB) irradiation during its storage at 4℃ for 15 days. The EB irradiation was found to be more effective than the UV-C irradiation for microbiological control. The pH tended to be increased by UV-C, EB irradiation, and storage period. Acidity was significantly higher in rice wine treated with EB irradiation than those of control and UV-C irradiation during storage period. The L*-value of the samples treated with UV-C and EB irradiation tended to be proportionately higher than that of the control, but this was not consistent during storage period. The a*-value of the sample treated with EB was higher than that of the others, but this was not consistent during the storage period. The reducing sugar content was higher in the control at day 0, but it rapidly decreased compared with the control during the storage. The results indicate that EB irradiation was more effective than UV-C irradiation in controlling microorganisms of rice wine. However, a further study is needed to minimize the rice wine quality deterioration caused by UV-C or EB irradiation during storage.

Endosulfan is an organochlorine pesticide that is widely used throughout the world for higher agricultural production. Its extreme toxicity, however, has caused health and environment concerns that have led to an interest in detoxification. In this study, the radiolytic degradation of endosulfan was investigated. Endosulfan in methanol solution (100 ppm) was irradiated at 0, 10, 30, and 50 kGy, and subsequent changes in immune toxicity and degradation of endosulfan were observed. The concentration of endosulfan that was used in this experiment did not affect the cell proliferation. The irradiation of endosulfan decreased the production of NO, indicating a decrease in the immune toxicity of endosulfan by irradiation. The concentration of endosulfan was significantly reduced by irradiation in a dose-dependent manner. The results suggest that gamma irradiation can degrade endosulfan and can reduce its immune toxicity.

The characteristics of the components related to the meat taste of the commercial broiler (CB) and the Korean native chicken (KNC) were compared. The breast meat from CB showed higher amounts of C16:1 and C18:2 but lower amounts of C16:0 and C22:6. The thigh meat from CB showed a higher amount of C18:1 but lower amounts of C16:0, C18:0, C20:4, and C22:6. The flavor- and taste-contributing amino acids, including aspartic acid, threonine, serine, glycine, alanine, tyrosine, lysine, histidine, and arginine, were significantly higher in the KNC breast meat, but the level of amino acids in the thigh meat were not different between the two breeds. The measurement of the volatile compounds revealed that CB contains much higher volatile compounds compared to KNC in their fresh breast and thigh meat. Both in the breast and thigh meat, however, the amount of flavor compounds increased significantly after cooking; as such, KNC turned out to have more flavor compounds than CB.