• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.15-22
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• 1980

In this study, two species of algae, Ecklonia stolonifera, Sargassum thunbergii and one species of marine plant, Zostera marina(rhizoid and stem) were collected and extamined to determine the extractability of water soluble protein and the influences of various factors including extraction time, temperature, ratio of sample vs solvent and pH upon the extractability were tested. The effects of precipitation treatments for isolation of algal protein from the extracts(TCA treatment, methanol treatment and pH control) were also tested. Amino nitrogen and total nitrogen of purified samples made by obtained optimum conditions were estimated. The effect of the ratio of sample vs solvent on extractability differed from species to species which was enhances at 1:100(w/v) in Sargassum thunbergii and Zostera marina while 1:150(w/v) for Ecklonia stolonifera. The effect of extraction time and temperature was revealed differently in all species which might be considered to be caused by differences in the constitution of algal tissues. But in case of TCA insoluble nitrogen, it was showed the maximum extractability at $40-50^{\circ}C$ for 1 hour extraction. The optimum pH for the ext action of total nitrogen was 9-12 while the optimum pH was 6-7 for TCA insoluble nitrogen. And the pH control appeared to be most effective in the influence of precipitation treatment for isolation of algal protein.

• Journal of Life Science
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• v.10 no.4
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• pp.326-332
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• 2000

In order to investigate the possibility of functional property improvement of meat products, four kinds of pork patties were prepared with water 10% as control, mugwort extract 10%, pine needle extract 10% and fatsia leaf extract 10%, respectively. In case of control moisture content was higher, but crude fat was lower, compared to patties treated with plant extracts. Crude ash content of pine needle extract treatment showed higher level than that of other patties. pH range of patties revealed to 5.92∼5.978. In raw patties Hunter's L-and a-value of control were higher than those of plant extract treatment, and a-value of raw patties showed higher level than that of cooked. Yield, water holding capacity, salt soluble protein extractability and gel strength among patties did not show significant differences. In control patty, fat retention was lower compared to other plant extract treatments, but water soluble protein extractability was higher compared to pine needle. Values such as hardness, springiness, cohesiveness, gumminess and chewiness were not significantly different among the patties. In sensory scores such as aroma, juiciness and palatability, significant differences were not observed among cooked patties, but texture score was higher in the order pine needle, mugwort, fatsia leaf and control.

• Korean Journal of Poultry Science
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• v.21 no.4
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• pp.249-256
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• 1994

This study was conducted to investigate the effects of the addition of varied levels of NaCI and phosphates to the breast meat of spent layers(2 \pm 0.2 kg), which were stabilized for over 24 h before slaughter, on the protein extractability, thiobarbituric acid(TBA) and volatile basic nitrogen (VBN). Within 1 h after slaughter, breast meat was removed and treated with NaCI(0, 1, 2, 3%) and phosphates(0.25% and 0.5%) using a hot-salted method. The breast meat samples were stored at 4\pm$1^{\circ}C$ for 3 d. The results obtained were summarized as follows. 1. Soluble protein contents of salt-treated groups were significantly higher than that of control (P<0.05) and showed a positive relationship with the levels of salt. At a constant level of NaCI, the soluble protein content was proportionately elevated by the levels of phosphates (P<0.05). It decreased significantly in both control and salt-treated groups during storage (P<0.05). 2. TBA values of salt-treated groups were significantly higher than that of control(P<0.05) and showed a positive relationship with the levels of salt. At a constant level of NaCI, TBA values in 0.5% phosphates treatment groups were significantly lower than that in 0.25%(P<0.05). It increased significantly in both control and salt-treated groups during storage(P<0.05). 3. VBN values of salt-treated groups were significantly lower than that of control(P<0.05) They increased significantly by the salt treatment for the first day of storage(P<0.05), but not from the second day of storage. VBN values in both control and salt-treated groups were significantly increased during storage(P<0.05). After the first day of storage and at the same level of NaCI, no significant difference in VBN value was observed between the two levels of phosphates.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.151-162
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• 1977

Distribution of marine algae is diverse in Korea and the resource of edible algae is abundant marking 239,037 tons of yearly production in 1976. They have been known as a protein source and used as a supplement in Korean diet. It is necessary to estimate the potentiality and properties of usable algal proteins especially as food resources and studies of extraction and separation of the proteins, therefore, are basically required for this purpose. In this study, the influence of various factors including the sample treatment, extraction time and temperature, sample us extraction solvent ratio and pH upon the extractability of the water soluble protein was determined. And the effect of precipitation treatment for isolation of the algal protein from the extracts was also tested. Nine species of algae, the major ones in consumption as food namely Porphyra suborbiculata, Undaria pinnatifida, Hizikia fusiforme, Sargassum fulvellu, Enteromorpha linza, Codium fragile, Sargassum kjellmanianum and Ulva pertusa were collected as fresh from Kijang, Yangsan Gun, in the vicinity of Busan city. The content of crude protein $(N\times6.25)$ of the algae ranged from $9.46\%\;to\;24.14\% showing the highest value in Porphyra suborbiculata and the minimum in Hizikia fusiforme. In the effort of maceration of blending methods on the extractability, immersion freezing in dry ice-methanol solution appeared most effective yielding 1.5 to 2.5 times extractability than that of the mortar grinding method. The effect of the ratio of sample vs solvent on extractability differed from species. It was enhanced at the ratio of 1:20 (w/v) in Ulva pertusa and Enteromorpha linza while the ratio was 1:30 (w/v) for Cedium fragile, Undaria pinnatifida, Hizikia fusiferme, Sargassum fulvellum and Porphyra suborbiculata and 1:40 for Sargassum kjellmanianum respectively. The effect of extraction time and temperature was revealed differently from species which might be caused by differences in the constitution of algal tissues resulting in that the extraction for 1 hour at $50^{\circ}C$ gave the maximum extractabilily in Ulva pertusa and Enteromorpha linza, 2 hours in Porphyra suborbiculata, Hikikia fusiforme, Undaria pinnatifida, Sargassum kjellmanianum and 3 hours in Codium fragile. And the extractability was higher at $50^{\circ}C$ to $60^{\circ}C$ for the most of the tested samples except Hizikia fusiforme. The optimum pH for the extraction was 9 to 12. The recovery of extractable nitrogen to the total nitrogen was $63\%$ in average with the first extracts and $8.6\%$ with the second extracts respectively. Both extracts were prepared by 2 hour extraction at $50{\pm}1^{\circ}C$ with dry ice-methanol frozen and seasand macerated materials. And these conditions assumed to be an optimum for the extraction of water soluble algal proteins since the nitrogen content after the first extraction covered $90\%$ of the total water extractable nitrogen. In the precipitation of the extracted proteins, Barnstein method and methanol treatment seemed to be more efficient than other precipitation methods.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.364-369
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• 1989

Experiments were carried out to investigate on the effect of cryoprotectants to the quality changes of pork and beef muscles during frozen storage . Beef and pork muscles were mixed with various cryoprotectants and stored at $-20^{\circ}C$ in a chest freezer for 12 weeks. Samples were analyzed for pH changes, TBA value, free atty acid contents, water and salt soluble protein extractability. The results obtained are summerized as follows. The pH value in all of cryoprotectants added samples were increased up to 0.25-0.5 as in non-treated samples . The TBA value, free fatty acid contents were increased with storage time as compared with the non-treated sample. Cryoprotectant effect on water soluble protein extractability was greater in pork than in beef muscle during frozen storage, especially in pork muscle treated CP-B, mixture of sorbitol, sucrose and sodium tripolyphosphate, as compared with non-treated sample. Cryoprotectant effect on salt soluble protein extractability during frozen storage was more pronounced in the beef muscle treated with CP-A which was mixture of sorbitol, mono sodium glutamate and sodium tripolyphosphate, and in the pork muscle treated with CP-B, mixture of sorbitol, sucrose and sodium tripolyphosphate than in the non-treated sample.

• Korean Journal of Poultry Science
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• v.25 no.2
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• pp.55-64
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• 1998

This study was carried out to investigate the postmortem changes in physico-chemical characteristics of chicken meat with different breeds. Thigh and breast meats from Korean Native Chicken(KNC, 15-wk old), Wangchoo(15-wk old), and broiler(7-wk old) were stored at 5 ˚C. Differences in postmortem pH changes were not recognized among breeds, and pH showed by the lowest value at the 1st day of postmortem in all breeds. Breast meat had tendency to drop pH faster than thigh meat. Heme pigment contents showed no differences among breeds. KNC showed the lowest cholesterol contents in all breeds, total collagen contents showed the lowest value at the 1st day of postmortem, and thereafter it was gradually increased. Heat soluble collagen contents was lowest in Wangchoo. Water soluble and salt soluble protein showed the lowest extractability at the 1st day of storage. Broiler showed the highest extractability of these proteins and Wangchoo showed the lowest. Water holding capacity(WHC) had increasing tendency whilst cooking loss had decreasing tendency by the ageing. WHC of breast and thigh meat showed the highest values in KNC and broiler, respectively. Myofibrillar fragmentation index (MFI) was significantly increased in all breeds by the ageing. Breast and thigh meat showed almost same MFI in KNC and broiler, and in KNC and Wangchoo, respectively. Hardness of breast meat showed decreasing tendency by the ageing.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.447-452
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• 1988

In order to study effect of freezing rates on the quality changes such as pH, TBA value, free fatty acids and protein extractability, cylindrical chopped beef logs with 10cm of diameter and 10cm of height were frozen at three freezing rates(0.97cm/hr, 2.05cm/hr, 3.71cm/hr)using air blast freezer. Physicochemical changes of frozen meat were investigated during forzen storage at $-20^{\circ}C$ for 16weeks. Results on pH change showed $0.1{\sim}0.2unit$ increase at the 16th week of the frozen storage and the change was smaller with the increasing freezing rates. Free fatty acids content and TBA value also were increased during forzen storage, but they were minimal at 3.71cm/hr freezing rate. Correlation coefficient between TBA value and free fatty acids content were highly significant(r=0.804). After 16weeks of storage, extractibilities of salt soluble protein were decreased by 17.7%, 6.1% and 1.6% at freezing rates of 0.97, 2.05 and 3.71cm/hr, respectively. On the other hand, extractabilities of water soluble protein were decreased by 26.0%, 21.2% and 18.5%, respectively. The effect of freezing rates on the protein extractability appeared to be greater in salt soluble protein than in water soluble protein, but freezing denaturation was more rapid in water soluble protein.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1285-1291
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• 2007

This research investigated variation in the improvement of the texture of chicken and pork sausages induced by microbial transglutaminase (MTG). The extractability of myofibrillar proteins from these sausages as well as the ${\varepsilon}-({\gamma}-glutamyl)$lysine (G-L)　content were also investigated. MTG treatment of sausages significantly increased the breaking strength values in both meat types, especially for samples incubated at $40^{\circ}C$. However, values of the breaking strength in both meat types were increased differently. The variation in protein extractability of samples incubated at $40^{\circ}C$ for both meat types could lead to some consideration of the mechanisms and the high accessions of myosin heavy chain (MHC) to MTG. SDS-PAGE analysis showed significant changes in the density of the bands after adding MTG, especially for the pork samples in which the bands disappeared totally. The G-L content in the presence of MTG was double that in control samples of both meat types. This study suggests that the binding ability of myofibrillar proteins with MTG is strong. This leads us to suggest that MTG functions positively with different improvements in the texture of chicken and pork products that are treated mechanically, such as sausages. Variability in gel improvement level between chicken and pork sausages was observed; this resulted from the variation in meat proteins in response to MTG, as well as to the original glutamyl and lysine content.

• Journal of the Korean Professional Engineers Association
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• v.17 no.4
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• pp.28-39
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• 1984

Experiments were carried out for the development of a processing method of soybean into full-fat or defatted flour, using two varieties of soybean (kwangkyo produced in Korea and Bragg produced in India) Samples were subjected to dry dehulling, size reduction and wet heat treatment processes to make soybean flours. The quality of soybean flours were evaluated, and the results obtained were summarized as follows. 1. Crude fiber content of dehulled soybean was under 3.0% which indicated satisfactory dehulling, and there was no significant difference in crude fibre content between two varieties. 2. When dehulled soybean was cracked into soy grits by a hammer mill, 98.71∼98.86％ of the soy grit was in the range of 10∼18 mesh which was the optimum size of particle for quick and uniform penetration of heat into the intra-particle air spaces. 3. Moisture content of soy flour after steam treatment at 15 psig for 5 to 30 min was only 0.29∼1.68% which did not hinder the next milling operation. 4. From the color analysis of soy flours, it was observed that the dominant wavelength for all the samples are in a very narrow range from 575 to 581 nm and the color variation was from yellow to yellowish orange. Twenty to twenty five ％ higher reflectance was observed in the defatted flours than full fat flours. The ％ chroma of the defatted flour slightly increased as the duration of steaming of soy grits increased, whereas that of the full-fat flour did not. 5. The protein extractability in the defatted flour at pH 7.6 showed progressive decrease in solubility from 48.40％ (Bragg), 75.20％ (kwangkyo) for untreated flours to 9.75％ (Bragg), 26.27％ (kwangkyo) for 30 min steaming. But Kwangkyo variety showed twice higher protein extractability than Bragg variety.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.871-875
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• 1999

This study was carried out to investigate the effects of freezing temperature on the quality of thawing aged beef loin. Drip loss was higher at 3oC freezing than at 20oC freezing, showing 17.21% drip loss after 6 days aging by 3oC freezing, 14.92% drip loss 12 days aging by 20oC freezing. Cooking loss by both water bath and pan boiling were decreased with increased in aging days. The salt soluble protein extractability of the beef loin was increased until 9 days aging by both 3oC and 20oC freezing, after that was decreased. The L value of the beef loin was high until 9 days aging by 3oC freezing, after that the L value of that was decreased. And the aging at 20oC freezing was high significantly with increased aging days. The a value of the beef loin was low significantly in 6 and 9 days aging by 3oC freezing, 20oC freezing was low significantly with increased aging days. The b value of the beginning of aging was higher with increased aging days. The percentage of denatured myoglobin of the beginning of aging was the highest, then those of 3oC and 20oC freezing showed 89.70% and 88.00%, respectively. The shear force of the beef loin was decreased with aging days, but the myofibrillar fragmentation index increased with aging days. The pH of the beef loin increased until 6 days of aging by both 3oC and 20oC freezing, after that the pH decreased.