• Food Science of Animal Resources
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• v.40 no.6
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• pp.1033-1043
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• 2020

This study investigated the impacts of gelatin hydrolysate addition on the technological properties and lipid oxidation stability of cooked sausage. Gelatin hydrolysate was prepared from pork and duck skin gelatin, through stepwise hydrolysis using collagenase and pepsin. The cooked sausages were formulated without gelatin (control) or with 1% pork skin gelatin, 1% duck skin gelatin, 1% pork skin gelatin hydrolysate, and 1% duck skin gelatin hydrolysate. The pH, color characteristics, protein solubility, cooking loss, and textural properties of cooked sausages were evaluated, and the 2-thiobarbituric acid reactive substances (TBARS) value was measured weekly to determine lipid oxidation stability during 4 wk of refrigerated storage. Enzymatic hydrolysis of gelatin decreased protein content and CIE L* but increased redness and yellowness (p<0.05). When 1% gelatin or gelatin hydrolysate was incorporated in cooked sausage, however, little to no impacts on pH value, moisture content, protein content, color characteristics, protein solubility, and cooking loss were found (p>0.05). The addition of 1% duck skin gelatin hydrolysate increased the cohesiveness and chewiness of cooked sausages. The inclusion of 1% duck skin gelatin accelerated lipid oxidation of cooked sausages during refrigerated storage (p<0.05), whereas duck skin gelatin hydrolysate caused a lower TBARS value in cooked sausage compared to duck skin gelatin. The results show comparable effects of gelatin and gelatin hydrolysate addition on the technological properties of cooked sausages; however, the oxidative stability of raw materials for gelatin extraction should be evaluated clearly in further studies.

• Culinary science and hospitality research
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• v.8 no.1
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• pp.95-105
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• 2002

This study was conducted to present the fundamental data on physicochemical properties of chicken foot collagen by the comparison with those from pork skin, which is present used in the factories as evaluate the usability of chicken foot in the industries of collagen production. Moisture content of chicken foot skin (CFS) was higher than that of pork skin (PS), and crude protein content was higher in PS. Content of other compositions was not different in both samples. At the evaluation of the soaking processing, effective time lapsed for soaking the skin in acid solution (acetic acid of 0.1 M) was about 12 hr for efficient extract ion of collagen, when tested by the changes of pH of the soaking solution and the increase of the weight of skins. L-Hydroxyproline of PS was slightly higher than that of CFS. Collagens were loaded in a SDS-PAGE and compared. Separated pattern of collagen of CFS was very similar to that of PS. Major collagen of CFS might be clarified as type I collagen.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.39-45
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• 2001

The pork meat has been reported as one of the food occurring allergic reactions predominantly to korean. To identify the potential food allergens in pork meat, sera were collected from 25 allergic patients to the pork meat and 10 allergic patients not to pork meat as well as 5 normal subjects after skin prick test and open food challenge test. Crude extracts were prepared by blending raw pork meat in phosphate buffered saline (pH 7.0) and the heat treatment on crude extracts was carried to characterize sensibility of the allergens to heat. ELISA was performed to determine specific IgE antibody levels of allergic patients to pork meat, and resulted in twofold higher mean value than that of tolerated patients. Extracted proteins from pork meat was separated with SDS-PAGE followed by immunoblotting using sera from pork sensitive patients and control subjects, respectively. The IgE binding response to pork meat by immunobots correlated with quantitative specific IgE value of each person. Immunoblots showed four prominent IgE-binding bands (66, 60, 50, 44 kDa) in crude extract, but two bands of those (60, 44 kDa) were heat-labile. These results suggest that most prominent allergens from pork meat are four components(66, 60, 50, 44 kDa) in korean and the heat treatment on allergen is additional parameter to characterize allergen.

• Korean Journal of Community Nutrition
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• v.13 no.6
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• pp.912-921
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• 2008

This study was performed to examine if the effects of collagen supplementation from pork skin could improve the sex steroid hormone, serum lipid and skin crack in Korean middle-aged women. Middle-aged women (40-55 years) who were not diagnosed with any type of disease were included in this study and thirty subjects were randomly assigned to a control group (n = 15) or a collagen supplemented group (n = 15). The collagen supplemented group ingested collagen flour 2 g, 3 times a day for 12 weeks. We measured serum collagen, estrogen, estradiol, estriol, progesterone, total cholesterol, triglyceride, HDL-cholesterol and LDL-cholesterol concentration. The collagen supplementation group had significantly increased serum collagen (p < 0.05) compared with the control group. In addition, skin crack was improved. But, there were no differences for sex steroid hormone and lipid profile in control and collagen supplemented groups. The result of the present study demonstrated that supplementation of 6 g collagen per day for 12 weeks can give beneficial effects on skin crack reduction and serum collagen concentration.

• Food Science of Animal Resources
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• v.32 no.1
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• pp.18-23
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• 2012

This study was conducted to survey the perception of domestic consumers about traditional pork dishes, and to utilize the survey result as a basis for the development of processed pork products. A survey was conducted on 218 domestic consumers regarding the following: general questions, propensity and preference to consume pork dishes, pork dishes feasible for export, and the types and problems of processed products feasible for export. The results of the survey showed that the respondents consumed pork dishes 3-4 times a month on average and they appeared to consume the pork dishes most frequently in specialized restaurants. The highest preference was shown in Samgyeopasal gui (grilled pork belly) and Galbi gui (grilled pork rib) among the pork dishes, whereas the lowest preference was shown in Kkubdegi gui (grilled pork skin) and Gookbob (boiled rice and pork served in soup). When the type of processed pork products available according to pork dishes were analyzed, the result showed that Samgyeopasal gui (grilled pork belly) and Nirbiani (slices of roast, seasoned pork in width) could be developed as a frozen product, Geyook Bokeum (stir-fried spicy pork), Bulgogi (Korean-style barbecued pork), and Galbi jjim (braised short ribs) could be developed as a retort product, and that Bossam (boiled pork eaten with a salty sauce and wrapped in greens), Pyeonyuk (slices of boiled pork), Jokbal (pork trotters), and Sundae (kneading together seasoned mixture of vegetables and glass noodles stuffing it into casings made of hog intestines, which are then tied off at the ends and boiled) could be developed as a vacuum-packed product. When the survey concerning the problems expected in the development of processed products using pork dishes was conducted, the result showed that there could be a texture change issue for Galbi gui, Samgyeopasal gui and Nirbiani; a preservation issue for Bossam, Pyeonyuk; a safety issue for Bulgogi and Geyook Bokeum; a taste and flavor change issue for Geyook Bokeum and Sundae; and a packaging issue for Gookbob.

• Food Science of Animal Resources
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• v.21 no.3
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• pp.215-226
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• 2001

The CLA used to add in diet was chemically synthesized by alkaline isomerization method with corn oil. To investigated the effects of conjugated linoleic acid(CLA) added diet feeding on CLA accumulation and blood characteristics of pork, a total of 64 Landrace was fed both CLA-free and CLA-added(0.3, 0.6 and 0.9%) diet for 1∼4 weeks. Cholesterol compositions in blood and CLA contents and fatty acid compositions of loin, belly, bone and skin were determined at 1, 2, 3 and 4 weeks after CLA added at fed. The HDL content in blood of all treatments was higher(P<0.05) than that of control and that of treatment 3 was higher(P<0.05) than that of other treatments among the CLA feeding periods. Palmitic, stearic and linolenic acids composition of loin and belly was increased but oleic, linoleic and arachidonic acids composition of them was decreased according to increasing the CLA feeding periods. CLA contents of loin and belly were higher than that of control and increased according to increasing the quantity of CLA and CLA feeding periods. CLA contents of bone and skin were higher than that of control, too. CLA content of skin was higher than that of bone. It was suggested that CLA could be accumulated in loin, belly, bone and skin by dietary CLA supplementation, and the CLA concentration and fatty acid composition in muscle could be affected by CLA level in diet and feeding period.

• Food Science of Animal Resources
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• v.34 no.2
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• pp.200-206
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• 2014

To determine the effects of grape skin and seed pomace (GSP) additions on the lipid oxidation susceptibility and the color change of cooked pork sausages, the chemical characteristics of GSP itself and the addition for two different levels of GSP (0.5 and 1.0% GSP, respectively) to sausages were examined. Both the redness and blueness of the GSP were significantly reduced as the pH level was increased from 5 to 7, but a reverse result was determined in the color tint and yellowness (p<0.05). The GSP polyphenol and flavonoid contents were influenced by the percentages of methanol solvents, and more flavonoids were established when 100% of methanol was applied as a solvent to the GSP. But, similar results were not observed in the polyphenol of GSP. In cooked pork sausages, significant decreases in the lightness and redness were found in both the 0.5% and 1.0% of GSP sausages during the storage period (p<0.05). However, an incompatible effect was observed in terms of yellowness, which increased as compared to the control sausage after 6 days of storage. The 0.5% addition of GSP decreased the levels of TBARS (p<0.05), but the ability of GSP to minimize lipid oxidation was not dose dependent. Therefore, the results indicated that the GSP is an efficient suppressor of lipid oxidation and has latent effects as a natural antioxidant when 0.5% of GSP is added to the cooked pork sausages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1028-1034
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• 2015

General composition and cholesterol contents of chicken 4 parts (breasts, thighs, legs without skin, and wings with skin) were analyzed. Fatty acids, amino acids, and mineral contents of breasts and thighs were also analyzed and compared with sirloin parts of beef and pork. Lipid contents of chicken parts (1.2% in breasts, 2.8% in thighs, and 14.9% in wings) were lower than those of beef and pork. Protein contents of chicken parts (22.9% in breasts, 19.7% in thighs, and 17.6% in wings) were higher than those of beef and pork. Cholesterol contents of chicken parts (99.0 mg% in wings, 80.8 mg% in thighs, and 56.7 mg% in breasts) were higher than those of beef and pork. However, saturated fatty acid contents of chicken (31.6~32.9%) was lower than those of beef (40.8%) and pork (42.7%). In the meanwhile, unsaturated fatty acid contents of chicken (67.1~68.4%) was higher than those of beef (59.2%) and pork (57.3%). Essential fatty acid contents of chicken (16.6~16.9%) were 1.6 times as high as that of pork (10.4%) and 5 times as high as that of beef (3.9%). Major amino acids composition were glutamic acid, aspartic acid, lysine, and leucine. Ten essential amino acid contents were 11,860 mg% in breasts and 10,454 mg% in thighs, and the ratio of essential amino acids (41.7~44.1%) was similar to those of pork and beef. Mineral contents of chicken were similar to those of pork and beef despites of slight different mineral contents in thighs and breasts.

• Physical Therapy Korea
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• v.10 no.1
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• pp.15-27
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• 2003

Therapeutic ultrasound is commonly applied for deep heating in physical therapy setting. However, it is difficult to determine the exact application dosage and to confirm the immediate heating effect. Microwave Radio-Thermometer (MRT) can measure the temperature by the electromagnetic energy in the microwave region of the object that emits above absolute zero temperature. MRT was used for early diagnosis of breast cancer since it was not harmful, non-invasive, and non-ionizing to the human body. The purposes of this study were to investigate how accurately 1.1 GHz RTM (RES Ltd. Russia) measures the change of average temperature in the tissue, and to determine the depth of temperature change measurement. Therapeutic ultrasound was applied (continuous wave for 5 minutes, 1 MHz, intensity of 1.5 $W/cm^2$ [in vitro] and 1.0 $W/cm^2$ [in vivo]) in four different conditions: (1) 30 cases of in vitro specimen of pork, (2) 30 cases of in vitro specimen of pork ankle joint, (3) 10 cases of in vivo canine thigh, and (4) 30 cases of in vivo human body. Intraclass Correlation Coeffients (ICC[3,1]) between average needle probe thermometer below surface and MRT temperature was revealed as followed: (1) Before ultrasound application ICCs ranges above .8 in specimen of pork (15 mm underneath the skin) and above .82 in specimen of pork ankle joint (10~30 mm underneath the skin). (2) After ultrasound application ICCs ranges above .7 in both specimens of pork and pork ankle joint. (3) Before ultrasound application ICCs ranges above .8 in canine thigh (20 mm underneath the skin). (4) After ultrasound application ICCs ranges above .82 in canine thigh. The temperature of the human body increased significantly with the mean of $15^{\circ}C$ in muscle tissue and with the mean of $3.5^{\circ}C$ in joint (p<.00). It was revealed that the average depth of temperature measurement of the tissue by MRT was in between 10 and 35 mm, and determined that the proper temperature measurement band was $36.5{\sim}37.0^{\circ}C$.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.266-272
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• 2004

The objective of this study was to investigate the physicochemical characteristics of gelatin extracted from pork skin under soaking in various acid solutions (lactic acid, acetic acid, and citric acid). Gelatin sol was extracted at 8$0^{\circ}C$, frozen at -2$0^{\circ}C$ and lyophilized it for 3 days to be completely dried in freeze drying unit. In the evaluation of gelatin quality, gelatin soaked in citric acid showed higher L- and a-values than those of any other gelatin (p<0.05). Gelatin treated by acetic acid showed the highest gel strength, cohesiveness, and brittleness. The content of hydroxyproline amino acid in gelatin treated by acetic acid was larger than one of gelatin treated in lactic and citric acid in order. From the experimental results, the highest quality of gelatin in all of period, which was soaked in acetic acid and lactic acid, has a more good quality than gelatin soaked in citric acid.