• Preventive Nutrition and Food Science
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• 제21권4호
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• pp.338-347
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• 2016

The present study investigated the volatile compound, physicochemical, and antioxidant properties of beany flavor-removed soy protein isolate (SPI) hydrolyzates produced by combined high temperature pre-treatment and enzymatic hydrolysis. Without remarkable changes in amino acid composition, reductions of residual lipoxygenase activity and beany flavor-causing volatile compounds such as hexanol, hexanal, and pentanol in SPI were observed after combined heating and enzymatic treatments. The degree of hydrolysis, emulsion capacity and stability, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, and superoxide radical scavenging activity of SPI were significantly increased, but the magnitudes of apparent viscosity, consistency index, and dynamic moduli (G', G") of SPI were significantly decreased after the combined heating and enzymatic treatments. Based on these results, it was suggested that the enzymatic hydrolysis in combination with high temperature pre-treatment may allow for the production of beany flavor-removed SPI hydrolyzates with superior emulsifying and antioxidant functionalities.

• Preventive Nutrition and Food Science
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• 제2권1호
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• pp.17-22
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• 1997

Casein was chemically modified with acetic, succinic, and maleic anhydride and changes in functional pro-perties were evaluated as affected by the degree of modification. Chemical modification resulted in casein with unique functional properties depending upon the type of anhydrid used and the degree of modification. It was possible to control heat coagulation, calcium precipitability, forming and emulsion capacity and stability. At pH 4.5 heat coagulation was 0% in the case 74.1% acetylated casein; on the contrary, succinylation and maleyation resulted in highly heat sensitive protein. Foaming properties were improved markedly by suc-cinylation and maleylation at pH 4.5. However, emulsifying properties were enhanced only by maleylation.

• Applied Biological Chemistry
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• 제35권4호
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• pp.265-271
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• 1992

키틴과 키토산으로부터 carboxymethylchitin, acetylchitin, ethylchitosan, N-acetylchitosan 및 chitosansulfate를 합성하여 그 물리화학적 기능특성을 키틴 및 키토산과 비교 검토 하였다. Carboxymethylchitin은 물과 아세트산에 용해되었지만 ethylchitin은 아세트산에만 용해되었다. 보수력은 N-acetylchitosan이 1194%로 키틴에 비해 약 2배 정도 높았으며, 지방흡수력은 carboxymethylchitin이 1800%로 키틴 511%에 비해 월등히 높았다. Carboxymethylchitin의 유화성이 75.91%로 가장 높았으며 그 다음이 미세결정형 키틴으로 57.02%였으나 키틴 및 키토산은 유화성이 나타나지 않았다. 색소흡착능은 acetylchitin이 0.93 mg dye/g sample(Blue R-250), 0.96 mg dye/g sample(Red-2)로 키틴 및 키토산 보다 높았다. 따라서 carboxymethylchitin은 유화제로서, acetylchitosan은 색소흡착제로서 이용이 가능할 것으로 판단된다.

• 한국식품조리과학회지
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• 제17권1호
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• pp.65-79
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• 2001

The effects of ${\alpha}$-chymotrypsin and trypsin treatments on the functional properties (degree of hydrolysis, solubility, and emulsifying capacity) of the soy protein isolate prepared from Jinpum soybean milk(JS milk) which has been developed as low lipoxidase-active soybean variety in Korea and extracted from commercially defatted soybean meal milk(DSM milk). The mixing ratios of JS milk to DSM milk were adjusted to 10:0, 7:3, and 5:5, respectively. The general quality attributes(yield, pH, titrable acidity, moisture contents, crude protein contents, color, textural properties, and sensory characteristics) of soybean cheese which has been prepared with the resulting soy protein hydrolysates were evaluated. Jinpum SPI was better subjected to trypsin than ${\alpha}$-chymotrypsin hydrolyses as indicated by better solubility and emulsifying capacity of the hydrolysates. The degree of hydrolysis and solubility of Jinpum SPI were higher than the soybean isolates from DSM milk. The increased ratios of DSM milk in the mixture resulted in the reduced yields and crude protein content along with the lowered titratable acidity while the pH values and moisture contents showed the opposite trends. In color characteristics, the increased amount of DSM milk brought about the significantly lower Hunter color reflectance values of lightness of the cheese products, along with the higher redness and total color difference value(ΔE). However, the enzyme treatment alone was not enough to cause any color differences. The increased ratios of DSM milk also caused the significantly lowered textural parameters such as hardness, adhesiveness and cohesiveness of the soybean cheese. Between the enzyme treatments, the ${\alpha}$-chymotrypsin treated samples resulted in the higher hardness and cohesiveness values of the products than those from the trypsin-treated ones. In organoleptic properties of the product, the better mouthfeel and overall quality scores were obtained from the trypsin treatments as compared with those from the ${\alpha}$-chymotrypsin ones. The mixing ratios of 10:0 and 7:3 were more favored than that of 5:5 as far as mouth-feel, yellowness and overall quality of the products were concerned. On the overall, the mixing ratio of 7:3(JS milk: DSM milk) and the trypsin treatment of the mixture was recommended for better manufacturing of high-quality soybean cheese.

• 한국식품과학회지
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• 제22권3호
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• pp.350-356
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• 1990

참깨와 들깨 단백질을 알칼리에서 추출시킨 후 참깨는 pH6.0, 들깨는 pH4.0에서 침전시켜 분리 단백질을 제조하여 그들의 기능성 즉, 용해도, 유화성, 기포성, 유지 및 수분 흡착력 등을 pH와 염농도를 달리하여 측정하였다. 단백질 용해도는 참깨 단백질이 pH6.0에서, 들깨와 대두 단백질은 pH4.0에서 가장 낮아 등전점을 보이었고, pH2.0과 pH8.0 이상에서는 크게 증가하였다. 0.1M NaCl 첨가시에는 참깨 단백질과 들깨 단백질의 경우 전 pH 범위에서 단백질 용해도가 증가하였다. 유화력은 각 시료 단백질의 등전점 부근에서 가장 낮았으며 0.1M NaCl 첨가시에는 모든 시료들의 유화력이 증가되었으나 0.5M NaCl 농도에서는 오히려 감소되는 경향이었다. 유화안정성은 유화력과 비슷한 크기로 나타나, $80^{\circ}C$에서 30분 가열에서도 이들 단백질이 열에 안정함을 보이었다. 기포 형성력은 참깨와 들깨 단백질이 대두 단백질에 비해 현저히 낮았으며, 0.1M NaCl과 0.5M NaCl 첨가시에는 모두 그 값이 증가되는 경향을 보이었다. 기포 안정성은 대두 단백질이 10분 이내에 크게 감소된 반면 참깨와 들깨 단백질은 30분까지 완만하게 감소하였다. 유지 흡착력은 들깨 단백질이 가장 높은 값을 보였고, 수분 흡착력은 시료간에 차이가 없었다.

• 한국수산과학회지
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• 제32권5호
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• pp.607-611
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• 1999

초음파를 이용하여 저분자 $\lambda$-carrageenan을 제조한 다음 그 특성을 조사한 결과 가용한계농도에 있어서는 대조구 $\lambda$-carrageenan는 $3\%$에서 가용한계농도를 나타내었고, 초음파 처리에 의해 저분자화가 많이 될수록 가용한계농도는 더 높게 나타났다. 알콜 침전도는 대조구에 비해 초음파 처리구가 낮게 나타났다. 유화능은 대조구에 비하여 처리구가 낮게 나타났으며, 분자량이 낮을 수록 유화능은 낮게 나타났다. 점도는 예상하였던 대로 초음파 처리에 의해 저분자화된 $\lambda$-carrageenan (P-1, P-2)이 대조구에 비해 낮았으며, 초음파 처리가 많이 될수록 점도는 낮게 나타났다. $\lambda$-carrageenan이 갈변반응에 대하여 크지는 않으나 어느 정도 갈변억제효과를 가지고 있는 것으로 나타났으며, 저분자화가 많이 될수록 갈변억제효과는 전반적으로 떨어지는 것으로 나타났다. 전기영동을 이용하여 $\lambda$-carrageenan 및 저분자화된 $\lambda$-carrageenan의 분자량을 조사한 결과 대조구 $\lambda$-carrageenan의 분자량은 약 250,000이었으며 초음파 처리에 따른 저분자화 된 $\lambda$-cariageenan의 분자량은 각각 184,000(P-1) 및 67,000 (P-2)정도 이었으며, GPC 결과도 이와 비슷하였다.

• 한국식품과학회지
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• 제23권6호
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• pp.702-710
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• 1991

세척 및 결체조직 제거 처리가 노계육의 성분, 기능적 성질, 저장성 및 조직감에 미치는 영향이 조사되었다. 수세처리, 중탄산용액 세척 처리 및 결체조직 제거 처리를 거친 노계육 시료의 경우 수분의 증가와 단백질, hydroxyproline 및 heme 색소 함량의 감소가 관찰되 었고 염용성 단백과 보수력의 증가 및 완충력과 유화력의 감소가 관찰되었다. 또한 처리 시료의 경우 대조구에 비하여 저장 중 TBA 값의 증가가 완만하여 저장성의 증가가 시사되었다. 중탄산 용액 세척 처리 및 결체조직 제거 처리를 거친 thigh육 및 drumstick육을 사용하여 제조한 시료 roll의 경우 대조 시료에 비하여 질긴 감이 적은 것으로 훈련된 관능평가 요원들에 의하여 판정되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권7호
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• pp.1021-1028
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• 2017

Objective: The objective of this study was to evaluate the effects of ageing time of lamb loins prior to freezing on technological characteristics and oxidation stability of coarse ground lamb loin sausage using in a model system. Methods: Lamb loins (M. longissimus lumborum, n = 25) were aged at $-1.5^{\circ}C$ for 0, 1, 2, 3, and 8 wk and then frozen for the remaining days (a total of 30 wk). The aged/frozen/thawed lamb loins were ground, and model sausages were formulated with 75% aged/frozen/thawed lamb loin, 25% water, 1.5% sodium chloride (NaCl) and 0.3% sodium tripolyphosphate. The pH and thaw/purge loss of aged/frozen/thawed lamb loins were evaluated, and protein functionality (protein solubility and emulsifying capacity), water-holding capacity and textural properties of model sausages were determined. Cooked model sausages were vacuum-packaged in a plastic bag and displayed under continuous fluorescent natural white light ($3^{\circ}C{\pm}1^{\circ}C$). Colour and lipid oxidation of the cooked model sausages were evaluated on 0 and 21 d of display storage. Results: Ageing prior to freezing had no impact on pH and purge/thaw loss of lamb loins and the colour of cooked sausages (p>0.05) made from the loins. Lamb loins aged for at least 3 wk prior to freezing numerically improved total and myofibrillar protein solubilities (p>0.05) and emulsion activity index (p = 0.009) of meat batter, but decreased cooking loss (p = 0.003) and lipid oxidation (p<0.05) of model sausages. Conclusion: This study suggests that post-mortem ageing of raw meat prior to freezing could improve water-holding capacity and lipid oxidative stability of sausage made from the meat.

• 한국식품과학회지
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• 제9권2호
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• pp.123-130
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• 1977

동방유량(東邦流糧)에서 공급(供給)받은 저변성(低變成) 탈지대두박(脫脂大豆粕)을 0.02N NaOH액(液)으로 추출(抽出)하여 Soy Protein Isolate (SPI)의 수율(收率)을 증류수나 염용액(鹽溶液)으로 추출(抽出)할때 보다 높이는 과정(過程)(84 % 수율(收率))을 확립(確立)하였으며 제조(製造)된 SPI는 92.1 %의 단백질(蛋白質)을 함유(含有)하였다. SPI를 $70^{\circ}C$에서 moisture heat를 하면 80분간(分間)에 5 %의 변성(變性)이 일어났으나 $95^{\circ}C$에서는 20분(分) 처리(處理)에 의(依)하여 95 %의 변성(變性)이 일어났다. SPI의 alkali 현탄액 (dope solution)은 SPI의 농도(濃度) 15 %, NaOH 농도(濃度) 0.6 %일때 7분(分)만에 60 poises를 나타내고 계속 안정(安定)된 점도(粘度)를 유지하였다. NaOH의 농도(濃度)가 0.9 %일 때는 시간(時間)이 경과(經過)함에 따라 점도(粘度)는 증가(增加)하였다가 감소(減少)하는 경향(傾向)을 보였다. syringe needle (dia. 0.3 mm)로서 모의(模擬) 실험(實驗) 결과(結果) 점도(粘度)가 $28^{\circ}C$에서 60 Poises일때 가장 적합한 단백질섬유(蛋白質纖維)의 texture를 보여주었다. 가열(加熱)에 의(依)한 SPI의 gelation은 8 %이상(以上)의 SPI농도(濃度)일 때 gel이 형성(形成)되기 시작하였으며 $100^{\circ}C$까지 안정(安定)한 gel을 형성(形成)하였고 SPI의 농도(濃度)가 12 %일때 $120^{\circ}C$에서 30분(分) 가열(加熱)에 의(依)하여 20,000 Poises의 좋은 점도(粘度)를 가졌으나 $120^{\circ}C$이상에서는 gel의 continuity가 떨어져 과립상(果粒上)의 gel이 생성(生成)되었다. SPI의 유화력(乳化力)은 pH가 8.7, NaCl의 농도(濃度)가 2 %일때 가장 큰 유화력(乳化力)을 나타냈다. milk casein과 비교(比較) 실험(實驗) 결과(結果) 유화력(乳化力)은 약간 낮았으나 염(鹽)이 존재(存在)하는 경우는 근사한 유화력(乳化力)을 보였다. 그러나 SPI의 foaming capacity는 foaming stability 면(面)에서 egg albumin이나 milk casein과 비교(比較)하여 양호(良好)한 결과(結果)를 보여주었다.

• 한국식품조리과학회지
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• 제9권1호
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• pp.43-51
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• 1993

Buckwheat protein isolate was tested for the effects of pH, addition of sodium chloride and heat treatment on solubility, emulsion capacities, emulsion stability, surface hydrophobicity, foam capacities and foam stability. The solubility of buckwheat protein isolate was affected by pH and showed the lowest value at pH 4.5, the isoelectric point of buckwheat protein isolate. The solubility significantly as the pH value reached closer to either ends of the pH, i.e., pH 1.0 and 11.0. The effects of NaCl concentration on solubility were as follows; at pH 2.0, the solubility significantly decreased when NaCl was added; at pH 4.5, it increased above 0.6 M; at pH 7.0 it increased; and at pH 9.0 it decreased. The solubility increased above $80^{\circ}C$, at all pH ranges. The emulsion capacity was the lowest at pH 4.5. It significantly increased as the pH approached higher acidic or alkalic regions. At pH 2.0, when NaCl was added, the emulsion capacity decreased, but it increased at pH 4.5 and showed the maximum value at pH 7.0 and 9.0 with 0.6 M and 0.8 M NaCl concentrations. Upon heating, the emulsion capacity decreased at acidic pH's but was maximised at pH 7.0 and 9.0 on $60^{\circ}C$ heat treatment. The emulsion stability was the lowest at pH 4.5 but increased with heat treatment. At acidic pH, the emulsion stability increased with the increase in NaCl concentration but decreased at pH 7.0 and 9.0. Generally, at other pH ranges, the emulsion stability was decreased with increased heating temperature. The surface hydrophobicity showed the highest value at pH 2.0 and the lowest value at pH 11.0. As NaCl concentrationed, the surface hydrophobicity decreased at acidic pH. The NaCl concentration had no significant effects on surface hydrophobicity at pH 7.0, 9.0 except for the highest value observed at 0.8 M and 0.4 M. At all pH ranges, the surface hydrophobicity was increased, when the temperature increased. The foam capacity decreased, with increased in pH value. At acidic pH, the foam capacity was decreased with the increased in NaCl concentration. The highest value was observed upon adding 0.2 M or 0.4 M NaCl at pH 7.0 and 9.0. Heat treatments of $60^{\circ}C$ and $40^{\circ}C$ showed the highest foam capacity values at pH 2.0 and 4.5, respectively. At pH 7.0 and 9.0, the foam capacity decreased with the increased in temperature. The foam stability was not significantly related to different pH values. The addition of 0.4 M NaCl at pH 2.0, 7.0 and 9.0 showed the highest stability and the addition of 1.0 M at pH 4.5 showed the lowest. The higher the heating temperature, the lower the foam stability at pH 2.0 and 9.0. However, the foam stability increased at pH 4.5 and 7.0 before reaching $80^{\circ}C$.