• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.163-168
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• 1973

In order to study on the effects of Bacillus natto on the soybean paste used natto, there were determind the contents of total nitrogen, amino acid, ammonia-nitrogen, total acid, reducing sugar and proteolytic activity etc. The results are summerized as follows; 1) Fermentation of natto paste were faster than koji paste and the fermentation period were sufficient in thirteen days. 2) The chemical components, color, taste and flavor of natto paste (added 15% natto) were excellent than the other soybean paste. 3) The contents of ammonia-nitrogen and amino acid of soybean paste were gradually increased during thirteen days in the fermentation, while total nitrogen contents were decreased. 4) After thirteen days of the fermentation, the contents of amino acid were decreased. 5) The contents of amino acid of natto paste were much more those of koji paste. 6) Total acid and reducing sugar contents indicated a rapid increased from nine to fifteen days during the fermentation, and a slower and decrease after fifteen days. 7) Total acid and reducing sugar contents of natto paste were somewhat higher than those of koji paste. 8) No significant difference was observed in the contents of reducing sugar and total acid according to the amount of natto added. 9) The contents of reducing sugar and amino acid were proportional to the proteolytic activity. 10) A flood soybean paste may be produced by adding 15% natto to the raw material in thirteen days of the fermentation.

• The Korean Journal of Food And Nutrition
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• v.33 no.2
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• pp.215-221
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• 2020

The purpose of this study was to investigate the protective effect on oxidative stress induced PC12 cells, and volatile flavor composition of essential oils derived from medicinal plant seeds- Gossypium hirsutum L. (G. hirsutum), Coix lachryma-jobi (C. lachryma-jobi) and Oenothera biennis (O. biennis). The essential oils were obtained by the solvent (hexane) extraction method from the seeds. The essential oils of the seeds were analyzed by the solid-phase micro-extraction gas chromatography mass spectrometry (SPME-GC/MS). The major compounds of G. hirsutum, C. lachryma-jobi and O. biennis were cyclonexanol (16.65%), β-asarone (14.29%) and ylangene (50.01%). The DPPH radical scavenging activity (IC₅₀) was the highest value of 8.52 mg/mL in the O. biennis. Additionally, IC₅₀ values of G. hirsutum and C. lachryma-jobi were 26.76 mg/mL and 36.81 mg/mL. For the oxidative stress on PC12 cells, we treated with hydrogen peroxide (H₂O₂). The pretreatment of oxidative stress induced PC12 cells with all the essential oils preserved or increased their cell viability and G. hirsutum and O. biennis attenuated the ROS generation (by 68.75% and 56.25% vs. H₂O₂ control). The results of this study suggest that the essential oils derived from medicinal plant seeds could be used as valuable back data as a natural essential oil material to prevent neurodegenerative diseases by protecting neuro-cells.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.707-716
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• 2010

Germinated brown rice is a useful material that contains natural nutrients and biologically active substances. This study was conducted to develop a optimal composite recipe for functional germinated brown rice cookie with added spinach (spinacia oleracea L) powder and with high preference in all age groups. The experimental design utilized herein was based on the Central composite design methodology of response surface, which included 16 experimental points, including 2 replicates for spinach, sugar, and butter. The physical, mechanical, and sensory properties of the test were measured, and these values were applied to the mathematical models. A canonical form and perturbation plot showed the influence of each ingredient on the mixed final product. The results of spread ratio decreased significantly with increases in spinach powder, sugar, and butter(p<0.01). L value shows that lightness decreased significantly with an increase in sugar(p<0.05), but the a and b values were not significant. Sensory evaluation found significant values for color(p<0.05), flavor(p<0.05), texture(p<0.05) and overall quality(p<0.05) in the predicted model. The optimum formulation by the numerical and graphical methods was calculated as follows: spinach powder 3 g, sugar 35.5 g butter 54.4 g.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.485-490
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• 2008

In this study, organic tea leaves were characterized with the aim of developing an organic beverage process. The green tea leaves grown using organic farming techniques were collected in Haenam, Korea. Catechins in green tea leaves were extracted by chloroform and ethyl acetate and these were then analyzed quantitatively and qualitatively by HPLC (high pressure liquid chromatography). The color and pH values of the green tea extracts were also measured. The catechin levels of April-harvested, May-harvested and June-harvested, semi-fermented leaves at 0.5% were 66.24, 29.19, 57.11, and 5.27 ${\mu}g/mL$, respectively. Among the detected catechins, the level of (-)-epigallocatechin gallate was the highest while that of (-)-epigallocatechin was not detected. The June-harvested leaves were selected as raw material for development of the green tea beverage, based on the levels of catechins, economic viability and yield of tea extract. As the level of extract increased, the levels of catechins of 0.1, 0.2, 0.5% also increased by 1.5, 11.78 and 41.01 times. From the results of the sensory evaluation of June-harvested leaf-extract, the sensory score of color was the highest in 0.1%, while the flavor and overall quality were the highest in 0.2%.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.549-553
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• 2010

Yeast strains with good sensory properties were selected, and those yeasts were subjected to mutation to develop high glutathione producing yeasts. In addition, the antiradical activity and flavoring effect of the yeast extract were evaluated. A total of 68 strains were screened, and three strains of Saccharomyces utilis, four strains of Candida utilis, and one strain of Zygosaccharomyces rouxii were selected based on the flavoring effect. Among them, a random mutation was elicited against SEM-Y8, resulting in a high flavoring effect and growth rate. The glutathione production by SEM-Y8 increased 2.0-fold following the mutation, and the DPPH radical quenching effect of the SY8-M2-1-derived extract increased 3.2-fold compared to that of the wild type. The sensory properties of the SY8-M2-1-derived extract were better than those of garlic or onion extract in umami and mouthfulness. Thus, the SY8-M2-1 extract could be used as a functional flavoring material with improved antiradical activity.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.54-61
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• 1998

Samjangs (Korean-style mixture of soybean paste) were prepared using magjang, traditional doenjang (Korean style soybean paste), and mixture of traditional doenjang and magjang (a kind of Korean style soybean paste) as a main composition. Charateristics including volatile compounds were investigated. Total sugar in samjang by using magjang was higher than that of other treatment while reducing sugar of the mixed treatment was high. Glutamic acid $(230.6{\sim}310.9\;mg/100\;g)$ was highest among free amino acids. Hunter color values of samjang with magjang was lower than those of others. Volatitle flavor components of smajang were identified with GC and GC-MSD. Fifty four components including 11 alcohols, 7 esters, 13 acids, 3 aldehydes, 4 alkanes, 4 phenols, 3 pyrazine and others were found in samjangs. Ethanol, acetic acid ethyl ester, 3-methyl butanoic acid, 2,4-hexadienoic acid and acetic acid might be major volatile components considering of high peak area. Pentanoic acid methyl ester and 4-methoxy-2-buten-1-ol were higher than other components in samjang with magjang while 2-methyl-1-propanol, butanoic acid and 3-methyl butanoic acid were in samjang with traditional doenjang and ethanol, acetic acid ethyl ester and 2,4-hexadienoic acid were in the mixed treatment.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.448-457
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• 1999

Citrus fruits are consumed worldwide due to their unique flavor and nutrition value. It is necessary to remove the haze material as well as to minimize the loss of major compounds such as organic acids, sugars, and ascorbic acid in membrane processes for clarification of juice. The objective of our research was to select the best membrane among one surface filter (Whatman No.4) and five microfiltration filters (GF/A, GF/D, GF/F, Gelman, and SM). Tangerine fresh blended with three times of water was partially clarified with 170 mesh followed by prefiltration in a Samduck filtration system. The best membrane was selected by measuring the amounts of major compounds in the permeates as well as the flux which were statistically analyzed with SAS program. The foulants on the membrane surface were observed by SEM. The flux of GF/A and GF/F decreased with time at probability 0.10. Gelman, SM, and GF/D maintained the stable flux. Gelman showed the highest total scores including nutritive value (the amounts of citrate, malate, and ascorbic acid) and purchasing need (brix and color). Therefore, the microfiltration membrane process was a very effective method in tangerine juice clarification and Gelman type A/E was proved to be the best membrane among the five microfiltration membranes.

• Food Science and Preservation
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• v.22 no.3
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• pp.361-368
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• 2015

In this study, the fermentation characteristics of Yakju were investigated by addition of protein and lipid. These are classified according to raw material (rice, glucose) and inducing substance (rice protein, rice lipid). Alcoholic fermentation occurred at $25^{\circ}C$, after 14 days. The results of this study were as follows: Alcohol content of Yakju with rice protein was higher than those of other samples. The pH and glucose of rice Yakju were detemied to be 4.86~5.13 and 4.17~4.86, respectively. Titratable acid and the total amino acid content of the Yakju with rice protein were the highest among other samples. The optical density contents of the rice Yakju and glucose Yakju were 0.52~0.653 and 0.27~0.61, respectively. The concentration of organic acids in rice Yakju (433.98~519.31 mg%) was higher than that of glucose Yakju (303.76~387.50 mg%). The major organic acid components of the Yakju were succinic, citric, acetic and lactic acids. The nitrogen compound concentrations of rice Yakju (4377.38~10208.06 ppm) was higher than that of glucose Yakju (671.20~9368.93 ppm). The protein odor correlation coefficient was 0.98 (p<0.001) showing a very high correlation coefficient, while lipid odor coefficient showed a negative correlation with -0.038 (p<0.458).

• Journal of Digital Convergence
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• v.11 no.10
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• pp.103-122
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• 2013

It has been realized that the flavor of coffee depends on the coffee-producing region and the growing condition. It has also been realized that the species of coffee beans influence the taste of coffee. However, coffee education is currently underway mainly for the simple job training of baristas such as roasting, extracting and customer service, and very little education on green coffee is being done. Therefore, this study is to contribute to the basic research material for the curriculum development of green coffee education. Through surveys to coffee instructors and students to investigate the current situation of green coffee education and awareness level of green coffee, the requirements of green coffee education has been analyzed. Further, the teaching direction and learning factors of green coffee have also been analyzed through Interview Analysis to coffee professionals. Based on the result thereof, this study is to suggest systematic lecturing-learning standards by presenting an education goal of green coffee, selection of education contents, determination of subject name, and composition and listing of education units to be learned. This study will be one of the basic research materials to plan and design the curriculum for green coffee education.

• Food Science and Preservation
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• v.20 no.2
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• pp.199-206
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• 2013

To evaluate peanut sprouts as a functional food material, the quality characteristics and antioxidant activities of soybean yoghurt with different percentages (0.5, 1.0, 2.0, and 3.0%) of peanut sprout powder (PSP) contents were investigated. The pH of soybean yogurt with PSP decreased in a time- and dose-dependent manner during fermentation, whereas the titratable acidity increased under the same conditions. The Hunter L value (lightness) decreased while the b value (yellowness) and a value (redness) increased as the PSP concentration in soybean yogurt increased. Prior to fermentation, the sugar content of the soybean yogurt increased as the PSP level increased, but the contents decreased as fermentation progressed. Meanwhile, the viscosity of the soybean yogurt increased during fermentation, and the lactic acid bacteria population was higher than that of the control. The sensory properties, including the flavor, color, taste, and overall acceptability, of the soybean yogurt containing 0.5 and 1% PSP, respectively, were higher than those of other tested yoghurts (with 0, 2.0, and 3.0% PSP contents). The antioxidant activity of the soybean yogurt significantly increased at the PSP concentrations of over 1.0%. These results suggest that the addition of PSP has beneficial effects on the quality and functionality of soybean yogurt, and that the addition of 1.0% PSP is the most suitable for manufacturing soybean yogurt.