천연물 유래 저분자 펩타이드들은 항산화, 고혈압 완화, 면역조절, 진통완화 및 항균작용 등 생리활성이 있는 것으로 알려져 왔다. 본 연구는 연산오계육 단백질을 상업용 프로티아제(alcalase, bromelain, flavourzyme, neutrase, papain, protamex)를 이용하여 저분자 펩타이드를 생산하고 항산화 활성(DPPH 소거능, 슈퍼옥사이드 라디칼 소거능, 하이드록시 라디칼 소거능 및 금속 킬레이션 능력), 펩타이드의 구성 아미노산 및 분자량을 분석하였다. 효소반응은 효소반응기에 다진 오계육 슬러리 50 g 와 단백질 효소 2%(w/v)를 넣고 pH6 와 온도 60℃ 조건에서 2시간 반응을 하였다. 반응 후 가수분해 도(%)의 범위는 36.65±4.10%에서 70.75±5.29% 사이의 범위를 보여주었는데 protamex의 가수분해도는 46.3%로 가장 높았으며, papain hydrolysate가 70.75±5.29%로 가장 높은 값을 보여주었으며, 반면에 alcalase hydrolysate가 36.65±4.10%로 가장 낮은 값을 보여주었다. DPPH 라디칼 소거능은 bromelain 처리 저분자 펩타이드가 가장 높게 나타났고, alcalase 처리 펩타이드에서 소거능이 가장 낮게 나타났다. 슈퍼옥사이드 라디칼 소거능 역시 bromelain 처리 저분자 펩타이드가 50% 이상의 가장 높은 라디칼 소거능을 보여주었다. 하이드록시 라디칼 소거능은 약 16.73에서 69.16% 사이의 분포를 보여 주었는데 bromelain 처리 저분자 펩타이드에서 가장 높게 나타났다. Fe2+ 킬레이션 능력은 약 17.85에서 47.84% 사이의 분포를 보여 주었다. hydrolysate들의 킬레이션 능력은 사용 효소들에 상관없이 큰 차이점이 없었다. 아미노산의 분석결과 alcalase, bromelain, flavourzyme, neutrase, papain, protamex 효소 가수분해 시켰을 때 차이점을 보여 주었고 가장 많은 아미노산은 glutamic acid이었다. 효소 hydrolysate들의 분자량의 분포는 처리 효소에 따라 분자량의 분포가 다르게 나타났지만 300-2,000 Da 범위에 있었다.
The processing properties of spent hen and broiler chicken were investigated before and after treatment to improve texture characteristics. Each treatment consisted steaming (S) with 85℃ for 20 min, Pulsed Electric Field (PEF) with 1.5 KV/cm for 4 sec, and Super Heated Steam (SH) with an oven temp. of 300℃, a steam temp. of 350℃ for 8 min. The yield of spent hen and broiler were 66.85% and 63.80% respectively in the control, but decreased in every treatment was lowest at 61.05% in the PEF treatment (p<0.05). In the color test, L value decreased, but the a and b values increased regardless of the species of spent hen or broiler. In the test of heating loss, the S treatment of spent hen had the highest result of 45.25% but lowest of 30.66% in the SH treatment of the broiler. When it was compared with various treatments, SH after PEF treatment showed the better result in terms of heating loss than the PEF or SH treatment respectively. In the test of texture, the broiler showed the lowest hardness of 5.57 kg in the SH (p<0.05). Otherwise, the spent hen resulted in 14.08 kg of hardness in steaming after PEF, but it improved significantly to 10.73 kg in SH after PEF. In the test of 9 scored sensory evaluation of overall palatability, 7.8 point was the best score with SH treatment in the broiler. The best score in spent hen was 6.3 point which was SH after PEF treatment. With this experiment, SH after PEF was the condition in the treatments to have the better texture of spent hen.
본 연구는 다양한 냉동과 해동처리에 따른 계육 가슴살에 natural microflora, 접종된 L. monocytogenes와 C. jejuni 수와 미세구조 변화 구명을 위하여 연구를 수행하였다. −20℃ 송풍식 냉동처리구의 총 호기성 세균과 C. jejuni 수는 4.06 log CFU/g과 4.09 log CFU/g으로 대조구와 비교하여 각각 약 0.7 log CFU/g과 1.0 log CFU/g의 감소를 보였다. 한편, 계육 가슴살 접종된 L. monocytogenes 수는냉동방법과 냉동온도에 따라 유의적인 차이를 보이지 않았다. 4℃와 25℃ 송풍식 해동처리구의 총 호기성 세균수는 3.70 log CFU/g과 4.02 log CFU/g으로 측정되어 대조구와 비교하여 각각 0.72 log CFU/g과 0.40 log CFU/g 감소한 반면 25℃ 유수식 해동처리구의 총 호기성 세균 수는 해동과정에서 균수가 급격히 증가하여 5.78 log CFU/g으로 관찰되었다. 해동 중 C. jejuni 수 변화는 해동방법보다 해동온도에 영향을 받는 것으로 나타났다. 냉동-해동반복 5회 후 총 호기성 세균과 효모 및 곰팡이 수는 감소하여 각각 4.15 log CFU/g과 2.30 log CFU/g을 보였다. 계육 가슴살에 접종된 L. monocytogenes 수는 냉동-해동 반복처리에 유의적인 영향이 없었지만 C. jejuni 수는 냉동-해동 반복 횟수가 증가함에 따라 감소하는 경향을 보였다. 냉동-해동 반복이 증가함에 따라 근섬유 조직을 재 손상시켰으며 특히 냉동-해동 반복 5회 후에는 계육 가슴살 시료의 조직세포 외부뿐만 아니라 내부에서도 공간이 발생하였으며 불균일하게 찢어진 세포가 관찰되었다.
The purpose of this study was to determine the optimal mixing conditions for two different amounts of turmeric (Curcuma longa L.) powder and olive oil for the processing of chicken sausage. The experiment was designed according to the central composite design of response surface methodology, with ten experimental points, including two replicates for turmeric powder and olive oil. The physicochemical and mechanical analysis of each sample, including water holding capacity, moisture content, lightness, redness, yellowness, hardness, chewiness, gumminess, and cohesiveness, showed significant differences. The results from sensory evaluations also showed very significant differences in color, flavor, tenderness, chewiness, and overall quality. The optimal formulation, calculated by numerical and graphical methods, was 1.89 g of turmeric powder and 9.77 g of olive oil. Under these conditions, the model predicted pH-6.01, salinity-0.20, WHC-94.88, L* value-61.13, b* value-37.45, hardness-36.66×102 (N), springiness-8.70 (mm), chewiness-26.88×103 (N×mm).
This study was conducted to evaluate the effect of dietary Yanggu original white kaolin supplementation on the growth performances, nutrients utilizability and meat composition of broiler. A total of 260 broiler chicks was alloted to 5 treatments with 4 replications and 13 chicks per replication. In addition to control group that fed diet without any kaolin supplementation, the treatments are designated by dietary supplementation as follows; white kaolin 400 mesh 1%(T1), white kaolin 10,000 mesh 1%(T2), white kaolin 400 mesh 0.8% + probiotics 0.2%(T3) and kaolin rizen(T4). The specific volume of 10,000 mesh white kaolin was higher than that of 400 mesh white kaolin (p<0.05) with no difference in pH between two different size white kaolins. Pellet durability of kaolins supplemented diet was improved, regardless of fat addition, compared to that of no kaolin supplemented diet. Both weight gain and feed intake of broilers in all the kaolin supplemented treatments were higher than that of control during d 0~21 period (p<0.05) but with no differences during d 22~40, On the other hand, kaolin supplementation into the control diet did not affect F/G of young broiler during d 1~21. Overall F/G of broiler was decreased by kaolin supplementation. Although there was no difference on ether extract, crude ash, total CHO and dry matter utilizabilities among all treatments, both crude protein and energy utilizabilities were improved by kaolin supplementation. Crude protein content of both broiler thigh and breast was the lowest in the kaolin and probiotics combined supplemented group(T3). In conclusion, the supplementation of physico-chemically treated white kaolin does affect growth performances, nutrients utilizability and meat composition of broilers. Therefore, the kaolin can be considered as a beneficial feed additive to improve broiler productivity.
The contamination levels of food poisoning bacteria was investigated from 350 samples of beef, 338 samples of pork, and 350 samples of chicken during the period from March 1996 to October 1998. The contamination levels of pathogenic organisms were higher in refrigerated meat than packed frozen meat and were relatively higher in chicken and packed meat than in beef. The highest level detected for each of the various pathogens was : less than 10,000 cfu/g for Staphylococcus aureus : less than 0.9 MPN/g for Salmonella and Literia monocytogenes: 7MPN/g for Campylobacter jejuni /coli. In the comparisions of cross- contamination ratio of tested meat for four species food poisoning bacteria 14.3% of beef, 23.5% of pork and 55.0% of chicken were contained only one species of pathogen, whereas 2.7 of beef, 5.6% of pork and 14.7% of chicken contained two species and 2.3% of pork contained a total of three species. Generally, pathogens was encounted higher isolation freguency in packed frozen chicken meat than in chilled chickens.
Microbial populations of total aerobic bacteria -and coliforming bacteria, TBA, Hunter's color value, heme pigments, muscle protein solubility, cooking loss and shear force were investigated for evaluating the shelf life of chicken legs gamma-irradiated at doses of 1, 3, 5 and 10 kGy with air-contained and vacuum-packaged methods. The initial microbial populations decreased with gamma irradiation depending upon the dose, and microorganisms in the vacuum-packaged samples were inhibited more than those in the air-contained samples. TBA values were higher in the air-contained samples than in the vacuum-packaged samples. Hunter's L and a values of the surface and inside of the legs increased by gamma irradiation, showing a bright red color and the red color was maintained during the storage of both samples. The concentrations of oxymyoglobin among the heme pigments increased by gamma irradiation. Muscle protein solubility slightly increased by increasing the applied dose. There were no significant differences in the cooking loss and shear force values. In conclusion, the combination of gamma irradiation and vacuum-packaging could extend the shelf life of chilled chicken without deterioration of the quality.
닭고기를 이용하여 소시지류의 제조 가능성을 검토하기 위하여 돼지고기와 닭고기에 인산함유 소금과 양념류를 첨가하여 cold cut을 제조하고 탈기포장하여 저장기간동안의 품질을 비교 연구하였다. 돈육 cold cut이 계육 cold cut보다 미생물의 증식이 더 빠르고 산가가 더 크게 감소하였으나 TBA가는 계육 cold cut의 증가폭이 더 컸다. 조직감 측정에서는 springeness, cohesiveness는 두 시료간에 유의적 차이를 보이지 않았다. 돈육 cold cut과 계육 cold cut의 관능검사에서는 색, 외관, 냄새에서 유의적 차이를 보였으나, 조직감, 풍미, 전체적인 수응도에서는 유의적 차이가 나타나지 않았다. 이러한 연구결과 닭고기를 이용한 소시지류의 제조 가능성을 볼 수 있었다.