• 한국식품과학회지
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• 제31권3호
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• pp.727-733
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• 1999

Endo- and exoproteases were used to hydrolyze Alaska pollack processing scrap. In 2 stage hydrolysis, the optimal conditions by Protamex were: temperature, $45.8^{\circ}C$; pH, 6.73; enzyme concentration, 0.11%; time, 105.5 min, whereas those by Flavourzyme were: temperature, $42.0^{\circ}C$; pH, 6.54; enzyme concentration, 0.28%; time, 20.4 hrs. But, the optimal conditions of 1 stage hydrolysis by equal proportion of Protamex and Flavourzyme were: temperature, $52.9^{\circ}C$; pH, 6.3; enzyme concentration, 0.46%; time 10.9 hrs. The contents of carbohydrate and ash were higher in the 2 stage hydrolyzate than the 1 stage, while that of crude lipid was in the reverse order. There were no significant differences in the contents of moisture and crude protein between both methods. The contents of total creatine and IMP, and viable cell counts were higher in the 1 stage hydrolyzate than the 2 stage, while the contents of TMAO, TMA, and Hx was in the reverse order. But, there were no significant differences in the contents of amino-N and color between both methods. The free amino acid contents of the 1 and 2 stage hydrolyzate were 2,741.77 and 3,529.47 mg/100 mL, respectively.

• Preventive Nutrition and Food Science
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• 제2권4호
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• pp.321-327
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• 1997

High Temperature-cooking conditions of cultured fishes(loach, crucian carp, bastard halibut, and jacopever) were optimized by response surface methodology(RSM), and plastein products were prepared using enzymatic hydrolysis. Four models were proposed with regard to effects of time(t), temperature(T), and water/fish meat (w/f) ratio on the amount of 0.3M TCA soluble fractions. The model coefficients were ranged from p<0.0001 for jacopever to p<0.0433 for bastared halibut. Cooking conditions for 60% hydrolysis were optimized at 1) 14$0^{\circ}C$ except for crucian carp(136$^{\circ}C$); 2) 10.08 hours(loach), 7.25 hours(crucian carp), 9.85 hours(ba-stard harlibut), and 9.37 hours(iacopever); 3) 1:1(w/f) ratio except for the crucian carp(1.1:1). When protein hydrolyzates were employed for the plastein synthesis, optimum plastein-reaction conditions were determined to be pH 9.0 with chymotrypsin for the loach and crucian carp hydrolyzates, pH 9.0 with papain for the bastard halibut hydrolyzate, and pH 11.0 with trypsin for the jacopever hydrolyzate. Plastein reaction could be performed in water at concentration up to 20%(w/f).

• ALGAE
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• 제18권4호
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• pp.341-347
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• 2003

The potential antioxidative activity of water-soluble enzymatic hydrolyzates from a kelp, Ecklonia cava was evaluated by free radical scavenging and lipid peroxidation assays. To prepare water-soluble hydrolyzates from E. cava the seaweed was enzymatically hydrolyzed by five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and five proteases (Protamex, Kojizyme, Neutrase, Flavourzyme and Alcalase). Among all the hydrolyzates, Celluclast hydrolyzate effectively scavenged free radicals released from DPPH (1,1-diphenyl-2- pricrylhydrazyl) and recorded around 73% scavenging activity at the concentration of 4 mg ${\cdot}ml^{-1}$. This hydrolyzate was thermally stable and DPPH radical scavenging activity remained 80% or higher at heating temperatures of 40 and 60$^{\circ}C$ up to 12 h and around 80% at 100$^{\circ}C$ up to 8 h. AMG and Ultraflo hydrolyzate inhibited the lipid peroxidation of fish oil as that of $\alpha$-tocopherol. These results suggested that an enzymatic extraction will be an effective way for the production of a potential antioxidant from seaweeds.

• 한국수산과학회지
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• 제25권2호
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• pp.93-102
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• 1992

In order to reduce long preparating time for alkali pretreated B-type gelatin, enzyme pretreatment was tried on flounder(Limanda aspera) skin for I-type gelatin. The optimal extraction conditions of the B-type gelatin were 9 folds of added water with material(w/w), 3 hrs of extraction time, $60^{\circ}C$ of extraction temperature and pH 5. The maximum amount of I-type gelatin was extracted at $60^{\circ}C$ for 3 hrs using water controlled to pH 6.0(material : water= 1:9, w/w). The yields of the B- and E-type gelatin were $64.2\%\;and\;59.2\%,$ respectively. The B-type was superior to the B-type in physical properties such as jelly strength, viscosity and electric conductivity. Molecular weight of B-type was so far larger than that of the E-type due to different pretreatment method. Hydrolysis ratio of the E-type was higher than that of the B-type because of its molecular weight. Results suggest that B-type product would be better than I-type as fish skin gelatin but E-type was desirable in hydrolyzate preparation.

• 한국수산과학회지
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• 제26권6호
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• pp.549-556
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• 1993

코끼리조개를 fast foods의 원료로 이용하기 위한 기초자료를 얻기 위하여 물리적 성상, 유리 및 구성 아미노산의 함량, 핵산관련물질, 월별 성분변화 및 냉동기간중의 선도변화를 측정 하였다. 3년생과 5년생의 경우 내장을 제거한 가식부의 수율은 각각 29.92, $38.04\%$이었다. 7월에 채취한 코끼리조개의 유리아미노산중 taurine함량이 가장 높았으며 Gly, Ala 및 Glu 함량도 비교적 높게 나타났다. 구성아미노산에 있어서는 Glu 함량이 가장 높았고 그 다음으로는 Ala이었다. 필수아미노산으로는 Leu과 Lys의 함량이 비교적 높았다. 월별 성분변화에 있어서 수분, 단백질은 3월, 4월에 가장 높았으며 지방과 글리코겐은 7월에 가장 높았다. 핵산관련물질중 5'-GMP의 량은 4월에 채취된 시료보다 7월에 채취된 것에서 더 높게 나타났다. 냉동저장중 VBN, TMA, $NH_2-N$의 함량변화에 있어서는 $95^{\circ}$에서 2분간 열처리한 시료는 열처리하지 않은 시료에 비하여 증가율이 낮았기 때문에 열처리조작이 선도유지에 효과적이었으며 냉동저장중 총 creatine함량의 변화에 있어서는 열처리 조작의 영향은 나타나지 않았다.