• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.132-138
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• 1998

To improve functional properties and enhance application of FPC in food industry, modified salmon FPC with enzyme treatment was produced and its general properties were investigated. Salmon FPC has over $84\%$ of protein and less than $0.18\%$ of lipid. Solubilities of FPC extracted with IPA and ethanol were very poor as less than $3\%$ in every pH range. In case of enzyme : substrate ratio of 1 : 100, degree of hydrolysis significantly increased until 4 hours and then slightly increased. No considerable differences were observed in general components of hydrolysates. Results of SDS-PAGE showed one unique band in each case and their molecular weight was less than 6,500. The flow properties of hydrolysates showed newtonian flow. Whiteness of hydrolysates were higher than that of salmon FPC as $5\~7$. There was no significant differences in the amount of peptide, but that of free amino acid slightly increased from 0.17 to 0.21 mg/ml.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.471-477
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• 1995

Extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds were analyzed to evaluate quality of anchovy sauce. The commercial products contained low proximate composition, extractive nitrogen and other extractive components, than the experimentally prepared anchovy sauce. Both samples, commercial products and experimentally prepared anchovy sauce, were rich in free amino acids, such as glutamic acid, leucine, alanine, lysine, and aspartic acid. The extractive nitrogenous components which consist of total nucleotides and related compounds, total free amino acids, methionine, isoleucine, valine, taurine, tyrosine, histidine, leucine, aspartic acid, cystine, and lysine, showed significant correlation(p<0.01) with extractive nitrogen. Possibly, seven kinds of free amino acids such as methionine, isoleucine, valine, taurine, tyrosine, histidine, and leucine, might be recommend as quality indices of standardization for anchovy sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.368-373
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• 1983

This study was designed to determine amino acid composition of silkworm larvae protein and to evaluate its nutritional value by rat experiment. Diets were divided into 5 groups; casein ($D_1$), soybean protein ($D_2$), soybean protein+20% silkworm larvae ($D_3$), soybean protein+40% silkworm larvae protein ($D_4$), and silkworm larvae protein ($D_5$). The growth rate, protein efficiency ratio, weight of organs, hematology, and the content of total serum protein and albumin were studied. The amino acid composition of silkworm larvae protein was comparable to the FAO provisional scoring pattern. The protein was especially high in the amount of lysine and methionine indicating that it could be a good supplemental effect for cereals and beans. Growth rate and protein efficiency ratio of silkworm larvae protein were better than soybean protein and these were increased by the addition of silkworm larvae protein. The weight of liver and spleen from silkworm larvae protein group were also higher than soybean protein group and RBC, WBC, Hct and Hb content of 5 groups tested were within the normal ranges. The contents of total serum protein and albumin from soybean protein group were increased by addition of silkworm larvae protein. From the results obtained, it could be stated that the quality of soybean protein might be improved by silkworm larvae protein.

• Reproductive and Developmental Biology
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• v.37 no.3
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• pp.129-134
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• 2013

A total of 30 Korean native pigs (gilt 15, boar 15) were used to investigate the carcass characteristics, meat quality, amino acid, and fatty acid composition by gender. The carcass weight of boars were significantly higher than gilts, whereas the carcass yield of gilts had significantly higher than boars (p<0.01). Boars had significantly higher moisture contents in loin muscle than gilts, whereas the protein contents of loin muscle had significantly higher in gilts than boars (p<0.01). In the results of meat quality analysis, the cooking loss (p<0.01), shearing force (p<0.05), lightness (L) and yellowness (b) in meat color (p<0.05) were significantly higher, but the pH was significantly lower (p<0.01) in gilts compared with boars. Arginine (p<0.05), alanine, aspartic acid, histidine, leucine, lysine, phenylalanine, serine, threonine and tyrosin (p<0.01) for gilts were significantly higher than those for boars. The results of fatty acid composition showed that gilts had significantly higher contents of C16:1n7, C18:1n9, C20:1n9 (p<0.01) than boars in intramuscular fat, whereas boars had significantly higher contents of C18:2n6, C20:4n6 (p<0.01) and C18:3n3 (p<0.05) than gilts in intramuscular fat.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.795-799
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• 1989

This study was carried out to hydrolyze lactose in commercial milk by ${\beta}-galactosidase$ from Kluyveromyces fragilis and to compare some physicochemical properties of yoghurts made from control and lactase-treated commercial milks. Quantitative analysis of sugars was performed by gas liquid chromatograph (GLC) on trimethylsilyl (TMS) derivatives. In commercial milk, 94.6% of lactose was hydrolyzed after 2 hours incubation at $40^{\circ}C$ with 6.0 units/ml of ${\beta}-galactosidase$. pH, titratable acidity and viable cell number of yoghurt made from lactase-hydrolyzed (LH) commercial milk were 4.1, 1.04% and $6.5{\times}10^8/ml$ of Str. thermophilus, $8.9{\times}10^8/ml$ of L. bulgaricus after 8 hours incubation at $40^{\circ}C$, respectively, The total contents of amino acid were 2.63% in control and 2.19%. in LH yoghurt. The total contents of free amino acid were 26.95 mg% in control and 17.55mg% in LH yoghurt. Analysis of free fatty acids resulted in that the contents of short chain fatty acids in LH yoghurt were a little higher than those in control. Both in control and LH yoghurt, the palmitic acid content was highest and that was followed by oleic and myristic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.3
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• pp.201-206
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• 1986

The purpose of this study is to prepare the fish sauce front mackerel scrap which usually comprises $40{\sim}50%$ of raw fish in processing. Mackerel scrap was chopped, mired with equal weight of water, and then hydrolyzed by autolysis. The optimal conditions for hydrolysis of .mackerel scrap were at $55^{\circ}C$ for 4 hours. The maximum hydrolyzed rate of protein was 65% by autolysis. Crude protein content (6.5%) and color of mackerel sauce were similar to those of traditional soybean sauce. The abundant amino acids in mackerel sauce were leucine (22.8%), isoleucine (15.0%), phenylalanine (12.6%) and valine (12.5%). In sensory evaluation, mackerel sauce was at least equal to the traditional soybean sauce in product quality.

• Food Science and Preservation
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• v.14 no.1
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• pp.61-66
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• 2007

This study investigated changes in physicochemical properties of onion powders during various drying conditions. The moisture content during vacuum drying at $40^{\circ}C$ remained at 5.23% for 5 days of drying, and it was possible to quickly obtain day powder Weight reduction upon $-70^{\circ}C$ vacuum drying was 90% after 7 days. The large change in browning caused by vacuum freeze drying was lowest ($OD_{420}\;of\;1.173$) after 7 days of drying. The content of vitamin C increased with vacuum freeze drying. The major free sugars were fructose, glucose and sucrose. Of organic acids, citric acid was prominent and, after vacuum freeze drying, showed a high value of 1,965 mg/100g. Free amino acids noted were L-arginine, ${\beta}-alanine$, L-alanine and L-threonine. In summary, vacuum freeze drying at $-70^{\circ}C$ is optimal.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.225-234
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• 1979

For the effective utilization of diverse and abundant resource of seaweeds in Korea as a food protein supplment, extraction conditions of water, salt, and alkali soluble proteins were investigated in previous work(Ryu and Lee, 1977: Lee et al., 1977: Lee et al., 1978). The present study as a part of the serial work was thus aimed to find the conditions of isolation and purification of extracted proteins, and to evaluate the nutritional quality of the isolated seaweed proteins in terms of amino acid composition, chemical score, protein score, modified essential amino acid index(MEAAI), and in vitro digestibility presented as pepsin-pancreatin digest residue index (PPDRI). As for the isolation of extracted proteins, TCA treatment was more effective for the proteins from rhodophyceae and Chlorophyceae while the precipitation at isoelectric point was more desirable for Phaeophyceae proteins. In amino acid composition, water soluble protein fraction was superior to the other fractions in Porphyra suborbiculata whereas both water and alkali soluble fractions seemed to bo more benefitial for Enteromorpha linza and Ulva pertusa; the extraction with alcohol-alkali mixed solvent for Undaria pinnatifida and Sargassum fulvellum. Glutamic acid and aspartic acid content was particularly high in all protein fractions examined. The total amino acid content of Porphyra suborbiculata and Enteromorpha linza was almost equivalent to that of dried whole egg although the essential amino acid content was lower. A comparative analysis was made on the inedexes between raw seaweed powder and isolated protein. Chemical score of Porphyra suborbiculata and Ulva pertusa was approximately 35 and 56 in cafes of raw powder and isolated protein respectively while only 10 to 16 for raw powder of Undaria pinnatifida and Sargassum fulvellum and 30 to 35 for their isolated proteins. Protein score of all isolated proteins was in the range of 63 to 73 which indicates that isolated protein would be mere valuable than the fern of raw seaweed powder. Digestibility by means of PPDRI was found to be extremely low in case of raw powder but it could be doubled in case of isolated protein yielding 67 to 70 for Porphyra suborbiculata and Ulva pertusa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.69-74
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• 1986

In order to examine the effect of 'Lactobacillus plantarum' inoculation on the maturation of cured loin ham, bacteriological and biochemical changes in meat were investigated during curing periods. The results were summarized as follow; On the bacteriological changes of cured ham, during curing periods, the number of coliform group were decreased. while psychrotrophic and halo-tolerant bacteria were increased until the 4 days. In the brine solution after the 7days of the curing, the number of coliform group were decreased the 7 days, but psychrotophic and halo-tolerant bacteria were increased until the 7 days of curing. The pH value of the meat and curing solution were sharply decreased at the one day, since these were slightly increased from 4 days. The color development of cured meat was showed 84.05 % development of within the 7 days of curing. Glutamic acid contents among the 17 kinds of amino acid were the highest at the 7 and 10 days of curing. The 13 kinds of fatty acids detected from at the all sample and total contents of unsaturated fatty acid were slightly decreased during curing.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.441-446
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• 1994

Seven commercial soybean paste were tested for ACE inhibition effect. In purification of ACE inhibitor from No. 2 soybean paste, acetone fraction $(50{\sim}80%)$ had 57% protein yield with 92.8% ACE inhibition effect. Inhibitor was purified from acetone fraction of soybean paste by Sephadex G-25, Sephadex LH-20 and ODS column chromatography and HPLC. $IC_{50}$ value of the purified inhibitor was 0.6 mg/ml. The inhibitor showed the competitive inhibition patterns on ACE. Amino acid analysis showed that the peptides consist of Ala, Phe, Leu, Glu, Gly, Ser, and Asp.