• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.153-153
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• 2003

우리나라와 일본에서 특유의 향미로 인해 오래 전부턴 조미식품으로 애용되었던 참기름은 최근 토코페롤과 세사몰류 항산화 성분의 인체 기능성으로 인해 유지시장에 서 더욱 증가일로에 있다. 지금까지 좋은 향미와 품질을 지닌 참기름을 얻기 위해 참깨의 roasting조건에 대한 많은 연구가 이루어져 왔으나, 가공 전처리인 이물질 제거를 위한 수세 작업 및 탈수 작업에 관한 연구는 아직까지 없었다. 따라서, 본 연구에서는 이물질을 제거하는 수세 작업을 한 후 수분의 제거 정도 즉, 참깨가 roasting 과정으로 들어가기 직전의 수분 함량이 참기름의 제조와 품질에 미치는 영향을 알아보고자 하였다. 시료 350g을 수세 후 24 hr, 48 hr, 120 hr 실온에서 송풍 건조를 시켜 참깨 자체의 수분 함량을 각각 17.14%, 11.78%, 6.08%로 조절하여 착유하였다. 수분함량이 다른 세 군 시료를 각기 24$0^{\circ}C$, 26$0^{\circ}C$, 28$0^{\circ}C$에서 20분간 roasting하여 착유된 참기름에 대해 이화학적 품질 특성을 알기 위해 seed와 oil의 색도, 산가, 과산화물가, TBA가, 점도와 굴절률을 측정하였다. 또한, sample single test(5점 척도)를 이용한 관능검사를 행하여 benny, nutty, burnt flavor 및 전체적 만족도와 향의 강도 항목을 조사한 후 상관분석을 실시하였다. roasted sesame seed와 oil에 대해 색도를 측정하고 분산 분석을 실시한 결과, 참깨의 색도 중 L＊가 R-suare=1로서 전체 자료가 모형을 잘 설명해줌을 의미하는데, 고수분 시료일수록 whiteness가 높게 나왔고(60이상), 고온일수록 미미한 감소가 나타났다. 이것은 수분함량이 시료의 건화속도에 요인자로 작용함을 말해준다. oil의 L＊도 마찬가지 경향을 보이나 고수분 시료구의 경우(40 이상), 타 시료구(20이하)에 비해 백색도가 높은 것을 볼 수 있어 볶음에 더 많은 시간을 투자해야 함을 보여주었다. 그러나 a＊와b＊는 시료구간 뚜렷한 차이는 보이지 않았다. 참기름에 대하여 화학적 품질 평가로 산가는 수분함량 시료구별로 1.204, 3.28, 1.862가 측정되었고, 과산화물가는 0.493, 0.169, 0.315가 기록되었고, TBA가 또한 13.45, 10.27, 11.73로서 시료의 수분 함량과 상관없이 초기 산패 경향은 거의 없는 것으로 나타났다. 참기름의 물리적 품질요소로서 점도는 평균 85.57 cS, 굴절률은 평균 1.471로서 시험구간 이화학적 차이는 없는 것으로 드러났다. 관능검사결과의 상관분석에서는 beany와 burnt flavor간에 -0.9975(p＜0.05)의 음상관을, nutty flavor와 전체favor간에 0.99662의 양상관(p$\leq$0.05)을 보였고, burnt와 향의 strength, 전체 favor와 nutty flavor간에도 상관성이 높았다. strength와 nutty 항목간에도 0.982의 높은 상관을 보였으나 전체 favor와 burnt 항목간에는 높은 음상관(-0.9862)을 보였다. 고수분 함량의 시료는 28$0^{\circ}C$의 고온 처리시 외에는 향미가 좋지 못한 것으로 나타났고, 수분량이 적은 실험구는 고온일수록 향과 고소함은 강해지나 수분 보유량이 적어 타 실험구에 비해 탄내가 많이 발생하였다. 향미 만족도는 중간 수분량, 26$0^{\circ}C$ 볶음 처리구가 가장 컸다. 결론적으로 수분함량을 10~12%로 조절한 시료로 26$0^{\circ}C$~28$0^{\circ}C$에서 20분 이내로 roasting할 때가 좋은 참기름을 얻을 수 있을 것으로 사료된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.739-747
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• 1997

This study was performed to clarify various conditions on the test of lipoxygenase-l and to establish the application of new test method for varietal improvement of soybeans in order to decrease beany flavors. Potassium borate and Tris were used as buffer and O.1M potassium borate solution showed the best result for the lipoxygenase-l test. In the range of pH 8.5~9.0 of the buffer, 2mM linoleic acid as substrate was effective. For color development, 100$\mu$l of two solutions(KI and starch) were added to the half soybean seed, successively. The substrate solution included linoleic acid was stored safely for 10 days at 4$^{\circ}C$ in refrigerator and for 4 days at room temperature. The best result was as follows; the 1ml of substrate solution[0.1M potassium borate(pH 9.0), 0.1％ Tween-20, 2mM linoleic acid] was added to the chipped half soybean seed in l.5ml plastic tube, waited for 15 minutes, and 100$\mu$l of color development solutions(5％ saturated KI in 15％ acetic acid, 1％ starch) were added to the tube, successively. After 4 hours, the purple color was observed in the upper phase of the plastic tube in the presence of lipoxygenase-1 and milky color in absence of lipoxygenase-1. The purple color was stable from 4 to 24 hours. There was no interfering effect by lipoxygenase-2 and -3. The plastic tube should be placed in the tube stand without shaking during the lipoxygenase-l test.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.151-159
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• 2000

The effects of bromelain and $\alpha$-chymotrypsin treatments on the functional properties(foaming capacity, foaming stability, emulsifying capacity, and emulsifying stability) of soy protein isolate(SPI) and the addition of various sweeteners(sucrose, sorbitol, xylitol) on the quality attributes(viscosity, overrun ratio, melt-down property, and sensory characteristic) of soy ice cream were studied. SPI was more effectively hydrolyzed with $\alpha$-chymotrypsin than bromelain, resulting in a better foaming and emulsifying capacity. Adding xylitol could significantly improve the viscosity, overrun and melt-down property of soy ice creams while the effect was the lowest in the sucrose addition. Bromelain treatment caused a lower apparent viscosity of SPI suspension compared with $\alpha$-chymotrypsin treatment and untreated. The overrun ratios of the soy ice cream prepared with bromelain and $\alpha$-chymotrypsin treated SPI were 18.9∼25.9% and 24.9∼40.3%, respectively as a result of freezing with agitation for 20 min in an ice cream maker. Comparatively, untreated SPI could bring only 15.8∼21.4% overrun ratios after operating for 15 min. The bromelain treatment caused high melt-down tendency of the product while soy ice cream with untreated SPI showed an opposite trend. In sensory characteristics, no significant differences in the strength of beany flavor were noted among the samples. Sweetness, bitter taste, icy feel, and mouthfeel of the product were greatly affected by the enzyme-treatment of SPI. Soy ice cream added with xylitol after $\alpha$-chymotrypsin treatment was the most acceptable among all samples.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.497-505
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• 1996

Defatted soybean meal (DSM) was microparticulated at cut-off whell speed of 9.000 rpm and air-classified into fine and coarse fractions at air classifying wheel speeds (ACWS) of 21,000, 18,000, 15,000 12,000 and 9,000 rpm stepwisely. Protein and ash content increased while lipid, carbohydrates and dietary fiber content decreased with decreasing ACWS. Amino acid composition and amino acid content of defatted soybean meal were similar to those of raw soybeans with aspartic and glutamic acid, the major amino acids. The yield and particle size increased with decreasing ACWS and mean particle size ranged from $4.9{\mu}m$ to $14.2{\mu}m$. The particles were oval-shaped with sharp corners. Water holding capacity, oil holding capacity and emulsion capacity slightly decreased with decreasing ACWS. Soybean curds formed showed different characteristics depending on the coagulant used and on the substitution ratio of full fat soybean flour with microparticulated DSM. Microparticulated DSM could successfully substitute wheat flour up to 10% level without bring no-ticiable beany flavor in the cakes.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.57-64
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• 1988

The present study was conducted to characterize lipoxygenase isoenzymes isolated from germinating soybean seeds to obstain pH profiles, carbonyl Production, carotene bleaching abilities, and stability to heat. The roles of these lipoxygenase isoenzymes in the generation of volatile carbonyl compounds were investigated to associate with off-flavor and odor of soybean sprouts cooked to different temperatures. Lipoxygenase isoenzymes were isolated from soybean sprouts using ammonium sulfate fractionation, gel filtration and ionexchange chromatography. Two main lipoxygenases exhibited maximum activity at pH 6.5 (lipoxygenase 2) and at pH 9.5 (lipoxygenase 1), respectively. Both lipoxygenase 1 and 2 produced 280 nm absorbing carbonlys and bleached carotene. The abilities of hydroperoxide formation, 280 nm absorbing carbonyl production and carotene bleaching of lipoxygenase isoenzymes were decreased significantly as the cooking temperature raised. Sensory evaluation data presented that raw and $50^{\circ}C$ cooked soybean sprouts showed significantly higher grassy odor than $80^{\circ}C$and $100^{\circ}C$ cooked soybean sprouts. On the other hand beany odor was significantly higher in $50^{\circ}C$ and $80^{\circ}C$ cooked soybean sprouts than in raw and $100^{\circ}C$ cooked soybean sprouts. These results indicate that lipoxygenase plays a role in the development of off-odor and flavors in soybean sprouts under the condition of chewing and inadequate heating.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.751-758
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• 1998

Lipoxygenase-deficient soybeans, Jinpumkong (lipoxygenase-2, 3 lacking) and Jinpumkong 2 (lipoxygenase-1, 2, 3 lacking), were breeded for the improvement of beany flavor problem. The objectives of this study were to characterize and to examine the storage stability of two lipoxygenase-deficient soybeans by comparing with Hwangkeumkong having high lipoxygenase activity. The crude protein and crude lipid content of Jinpumkong 2 were lower than those of Hwkangkeumkong and Jimpumkong. All soybean samples were middle-sized and yellow-coated seeds. The rate of water uptake and trypsin inhibitor activity of Jinpumkong were greater than those of others. The cooking rate of Hwangkeumkong was the highest among all. The lipoxygenase activity of Hwangkeumkong was decreased when the soybeans were stored at $40^{\circ}C$ for 96hrs at 90% RH which is the condition of accelerated aging. After accelerated aging, the germination ratio of Hwangkeumkong was not changed but the ratio and speed of germination dropped rapidly in Jinpumkong and Jinpumkong 2.

• Journal of Dairy Science and Biotechnology
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• v.30 no.2
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• pp.111-117
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• 2012

A number of recently developed cheese analogues that are available in dairy food markets are currently being produced for improving health or diet, and they include Mozzarella, Cheddar, American, Muenster, and other custom flavors. Cheese analogues have many benefits such as extended-and-improved shelf life, price stability, and functional qualities that include better texture, higher melting point, and better stretching properties. Various cheese analogues can now be made by using soybeans or soy protein products, gelatin, gum arabic, and other ingredients. Hence, in this study, on the basis of previously published studies, we recommend soy protein for cheese analogues, for improving the texture and flavor of cheese analogues. Moreover, the best conditions for making cheese analogues and the factors that affect the characterization of cheese analogues have been described in this paper.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.720-728
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• 2014

In order to characterize the quality of Doenjang, fermented Korean soybean paste, subjected to long-term aging, this study performed physico-chemical analyses and sensory evaluation according to aging period (from 1 to 9 years). Regarding the proximate composition of Doenjang according to aging period, moisture, crude protein, crude lipid, crude ash, and salt contents showed little differences among Doenjang samples. Amino-type nitrogen content was 1,046.7 mg% in the 1 year-aged sample, 990.9~996.9 mg% in the 2~5 year-aged samples, and 1,214.1~1,304.8 mg% in the samples fermented more than 5 years. ${\Delta}$E value, reflecting total color differences between the samples, increased according to aging period. Ratios of linoleic and linolenic acids, which are essential fatty acids in soybeans, constituted 55% of total fatty acids, which was the most abundant among all fatty acids. The major free sugar in Doenjang was fructose at a content of 1.6~2.2% in 1~9 year-aged Doenjang. Glycoside form of isoflavones in Meju constituted 77.1%, and the aglycon form constituted 22.9%. However, the glycoside type of isoflavones in soybeans was converted to aglycon type in Doenjang through fermentation and aging. In the sensory evaluation of Doenjang samples, brown color, salt smell, soy sauce flavor, and viscosity all increased according to aging period, whereas sweet flavor, roast smell, beany flavor, salty taste, and acrid taste showed no significant differences. In cluster analysis of the sensory attributes of Doenjang according to aging period, 1 year-aged Doenjang was significantly different between 2 year- and 3~5 year-aged Doenjang.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.43-50
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• 2002

This study was carried out to evaluate the quality attributes of frozen soy yogurts prepared by freezine soy yogurts, which are made of different types of Bifidobacteria (B. bifidum, B.breve, B. infantis) and oligosaccharides (fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides) containing $\alpha$-chymotrypsin treated soy protein isolate were evaluated in terms of overrun, melt-down quality, changes in the total number of Bifidobacteria after freezing, and sensory evaluation. The quality attributes of soy yogurts were also evaluated in terms of changes in the number of viable cells of Bifidobacteria in soy yogurts after incubation at 37$\^{C}$, pH 3.0 for 90 min, water holding capacity, and viscosity. The overrun of frozen soy yogurts fermented by B. bifidum showed the hiehest value but those fermented by B. infantis showed the lowest, while the melt-down quality of soy yogurts were vice versa. The total numbers of Bifidobacteria after freezing for 30 min in ice cream maker showed more than 10$\^$9/ CFU/ml. In sensory evaluation, all $\alpha$-chymotrypsin treated frozen soy yogsurt showed little beany flavor. In sour, sweet, and bitter tastes and mouth feel, the frozen soy yogurts fermented by B. bifidum evaluated better but those fermented by B. infantis evaluated worse. Also in the overall quality, the frozen soy yogurts fermented by B. bifidum were evaluated desirable but those fermented by B. infantis were evaluated undesirable. The water holding capacity and viscosity of soy yogurts fermented by B. bifidum showed the highest values but those fermented by B. infantis showed the lowest values. The total numbers of Bifidobacteria of all soy yogurts decreased from 10$\^$9/ CFU/ml to 10$\^$8/ CFU/ml after incubation at 37$\^{C}$, pH 3.0 for 90 min.