• The Korean Journal of Food And Nutrition
• /
• v.15 no.3
• /
• pp.228-234
• /
• 2002

In this paper, we proposed a preparation of Jeung- pyun (Korean fermented steamed rice cake with sour taste and spongy texture) using fuzzy theory. Before this preparation was introduced, it thoroughly analyzed the existing data of Jeung-pyun preparation with sensory evaluation and instrumental measurement. It defined a membership auction of Fuzzy set by analyzed three sorts of data on Jeung-pyun. And it established the Fuzzy model using the quantity of materials as input, such as rice, flour, wheat flour and fermentation time, and the sensory test scores as output, such as grain, softness, sourness, chewiness, overall quality, pH value and volume, respectively. We got the results that the Fuzzy model was accord with the conventional method with sensory evaluation. And the validity of this method is shown through the computer simulation of the test data. Therefore, the proposed method by Fuzzy model will apply to make Jeung-pyun without sensory evaluation. This study will contribute to develop standard preparation for korean foods and expert system of preparation using computer system.

• Korean Journal of Food Science and Technology
• /
• v.34 no.2
• /
• pp.232-237
• /
• 2002

The quality of bread (black rice bread) made of black rice flour and wheat flour was investigated. The bread was manufactured with 10, 20 or 30% black rice flour (BRF) (w/w) with increasing and wheat flour. The bread volume was decreased from 2250 cc to 1700 cc as BRF contents increased from 0% to 30%. The lightness (L values) decreased with increasing BRF contents and the redness (a values) increased. The yellowness (b values) slightly decreased with increasing BRF contents. Textural characteristics of bread crumb were influened by adding additives BRF. Breads containing additives showed an increase in hardness, gumminess and chewiness and a decrease in springness and cohesiveness. In sensory evaluation, sensory scores decreased with increasing BRF contents for the appearance, such as grain and texture, of black rice bread. On the other hand, the highest sensory scores for color, taste and overall eating quality were obtained, when BRF content was 20%. In conclusion, Bread with 20% BRF was the best quality in sensory evaluation.

• Food Science of Animal Resources
• /
• v.23 no.3
• /
• pp.262-268
• /
• 2003

Kefir is a traditional fermented milk in Caucasusian area and is made mainly of milk fermented with lactic acid bacteria and yeasts. Six typical kefir grains were selected from ten kefir grains collected from different locals in Korea. Kefir grains were gelatinous in texture and had various shapes of villi, grapes, leaves, hulled millets, and towels. To investigate predominant microflora of kefir grains, SPC, MRS, M17, Rogosa, and APT agar media were used for viable cell count MRS, SPC, and Rogosa media were most acceptable for bacterial cell counts of the selected kefir grains. From one or two of the SPC agar plates which contained around 25∼50 colonies, all grown colonies were isolated and identified. Most predominant bacteria was identified as Lactobacillus fermentum by API 50 CHL kit. The proportions of Lb. fermentum and Lb. brevis among the total identified bacteria were around 41~88% and M4%, respectively. To select the best preservation method for kefir grains, refrigeration, freezing, and freeze drying were compared. Freeze drying was found most suitable for the preservation of kefir grains, based upon their acid-producing activities and production of off-flavors.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.6
• /
• pp.1120-1128
• /
• 2001

This study was to investigate the flour quality and bread making condition required for Korean-style steamed bread, using 5 commercial wheat flours (protein content from 8.2 to 12.5%), They were compared in making steamed bread (SB) and baked roll bread (BRB). Straight dough method was used and the temperatures of dough and fermentation were controlled at 26$^{\circ}C$ and 32$^{\circ}C$, respectively. The first fermentation was conducted at various times (0, 20, 40 and 60 min) and then forty min of proofing (2nd fermentation) was used for all bread dough. As the 1st fermentation time increased, volumes of both SB and BRB increased 4.3 ~8.7% and 27~40%, respectively, but the SB flattened and the total bread scores of SB decreased due to the lack of smoothness and shininess of the bread surface and poor grain. Contrary to that, the total bread scores of BRB increased. SB made from the flour containing 10.5% of protein, was of its highest quality: relatively high volume, smooth, semiglossy and white surface, good texture, followed by SB made from flours containing 10.9%, 9.5%, 12.5%, and 8.2% of protein content, respectively These results suggest that the 1st fermentation process was not needed for SB making. Total bread scores of SB were better correlated with farinograph dough stability than protein contents and volumes of SB were correlated with farinograph development time. Therefore, in steamed bread making, flour dough rheology is important as well as protein content.

• Journal of the Korean Magnetics Society
• /
• v.21 no.2
• /
• pp.77-82
• /
• 2011

The use of soft magnetic materials have been increasing in the various industrial fields according to the increasing demand for high performance, automatic, miniaturing equipments in the recent our life. In this study, we investigated the effect of factors on the core loss and magnetic properties of electrical steel and soft magnetic composites. Furthermore, we reviewed the major efforts to reduce the core loss and improve the soft magnetic properties in the two main soft magnetic materials. Domain purification which results from reduced density of defects in cleaner electrical steels is combined with large grains to reduce hysteresis loss. The reduced thickness and the high electrical conductivity reduce the eddy current component of loss. Furthermore, the coating applied to the surface of electrical steel and texture control lead to improve high permeability and low core loss. There is an increasing interest in soft magnetic composite materials because of the demand for miniaturization of cores for power electronic applications. The SMC materials have a broad range of potential applications due to the possibility of true 3-D electromagnetic design and higher frequency operation. Grain size, sintering temperature, and the degree of porosity need to be carefully controlled in order to optimize structure-sensitive properties such as maximum permeability and low coercive force. The insulating coating on the powder particles in SMCs eliminates particle-to-particle eddy current paths hence minimizing eddy current losses, but it reduces the permeability and to a small extent the saturation magnetization. The combination of new chemical composition with optimum powder manufacturing processes will be able to result in improving the magnetic properties in soft magnetic composite materials, too.

• The Journal of the Petrological Society of Korea
• /
• v.26 no.4
• /
• pp.311-325
• /
• 2017

Peridotite xenoliths in middle Miocene alkaline basalt from the Mt. Baekdu area are mainly anhydrous spinel lherzolites, displaying coarse-grained protogranular texture. These xenoliths have late-stage secondary orthopyroxene replacing olivine as the metasomatic mineral and glass formed along the grain boundaries. The studied xenoliths are characterized by the high $Mg{\sharp}[=100{\times}Mg/(Mg+Fe_{total})$ atomic ratio] of olivine, orthopyroxene and clinopyroxene (89~92) and the $Cr{\sharp}[=100{\times}Cr/(Cr+Al)$ atomic ratio] of spinel (10~29). Based on major-element data, the studied xenoliths are similar to those from the abyssal peridotites. Clinopyroxenes of the xenoliths are mostly enriched in incompatible trace elements, exhibiting two types of REE patterns: (1) LREE-depleted with $(La/Yb)_N$ of 0.1~0.2 and $(La/Ce)_N$ of 0.4~0.8. (2) LREE enriched with $(La/Yb)_N$ of 2.2~3.8 and $(La/Ce)_N$ of 1.2~1.6. The calculated equilibrium temperatures and oxygen fugacities resulted in $920{\sim}1050^{\circ}C$ and ${\Delta}fO_2(QFM)=-0.8{\sim}0.2$, respectively. It is suggested that the Mt. Baekdu peridotite xenoliths represent residues left after variable degrees of melt extraction(less than 15 vol%), which was subsequently subjected to different degrees of modal/cryptic metasomatism by silica- and LREE-enriched fluids (or melts).

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.3
• /
• pp.451-459
• /
• 2002

High strength flour (12.5% protein) and low strength flour (10.5% protein)were used to determine optimum formulation far steamed bread added with green tea powder (GTP). The response surface study consisted of the following independent variables : GTP (1.5∼4.5%), mixing time (8∼14 min), fermentation time (30∼50min). Bread Quality attributes measured for total bread score of each combination were loaf volume, spread ratio, surface glossiness, smoothness, grain and texture (firmness, cohesiveness, elasticity and adhesiveness). The required amount of GTP, mixing time and fermentation time for steamed bread made from two kinds of flour were different. GTP could be more added to lower strength flour than higher strength flour without losing bread quality. GTP highly affected the loaf volume, spread ratio, surface smoothness, firmness and total bread score of steamed bread (p<0.001). The results suggested that the functional steamed bread added with GTP having excellent quality can be made from low strength flour using green tea powder 3.2%, mixing time 11 min 8 sec and fermentation time 39 min 55 sec.

• Korean Journal of Food Science and Technology
• /
• v.51 no.3
• /
• pp.214-220
• /
• 2019

Four rice varieties (Boseogchal for waxy, Baegjinju for medium-waxy, and Seolgaeng and Haiami for non-waxy) were milled to 2% degree of milling (DOM), and physicochemical and sensory properties of 2% milled rice (2% MR) were compared to those of brown rice (BR). No significant differences in the approximate compositions of BR and 2% MR were observed, whereas the grain color of 2% MR was slightly brighter than that of BR. For all varieties, water absorption ratio of BR was significantly increased by milling. The pasting properties of rice varied significantly depending on the variety, but there was no significant difference in peak and through viscosities between BR and 2% MR. Analysis of the texture of cooked rice showed that milling to 2% DOM caused a significant decrease in hardness, but an increase in adhesiveness and stickiness. Cooked Seolgaeng 2% MR scored significantly higher in the sensory evaluation than the corresponding BR. These results suggest that 2% DOM would be useful for improving the sensory properties of cooked non-waxy rice.

• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.6
• /
• pp.834-839
• /
• 2007

This study was designed to determine the optimal ratio of dropwort powder in castella by adding the powder at levels of 0, 3, 6, 9, and 12% respectively. The properties of the castella were analyzed by specific gravity, specific volume, color determinations, texture properties and sensory evaluation. The Specific gravity increased with increasing amount of dropwort powder. However, the specific volume decreased with increasing dropwort powder. For the color values, as more dropwort powder was added, the L-value decreased. The castella with 9% dropwort powder had a higher hardness, gumminess, and chewiness. A sensory panel perceived that the external and internal color of the castella become darker with the dropwort powder substitution and the grain size decreased with increasing amount dropwort powder, while sweet taste showed no significant difference. The order of overall preference was DP 9>DP 6>DP 12>CON>DP 3. Therefore, the substitution of 9% of wheat flour with dropwort powder was recommended in the production of castella.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.4
• /
• pp.550-556
• /
• 2014

Rice bran contains both excellent nutritional value and functional advantages. Its utilization is limited due to reducing texture and low storage. To satisfy various tastes, Bacillus spp. having high amylase and protease activities were selected. Using the strains, we made whole grain soybean Meju with a reduced manufacturing period by increasing the concentration of total nitrogen. We made soy sauces with mashing ratios of soy bean and rice bran at 10:0, 9:1, 7:3, and 5:5, and then compared their physiochemical properties. After 2 weeks of fermentation, the sugar content increased from 21~22% to 30~32%. However, pH and salinity showed no differences. At a ratio of 9:1, total nitrogen, amino nitrogen content, and total free amino acid contents were the highest at 1.62%, 652.52 mg%, and 8,804.03 mg/kg, respectively, compared to other mashing ratios of soy bean and rice bran. Especially, the contents of aspartic and glutamic acid, which increase delicate flavoring, were higher in our soy sauce compared to those of general traditional soy sauce and brewed soy sauce, which were 504.25 and 1,262.25 mg/kg, respectively. Serine and alanine, which are related to sweet taste, were present at 49.50 and 518.75 mg/kg, respectively, which were the highest among all mixing ratios, at a ratio of 9:1. Compared to general traditional soy sauce and brewed soy sauce, the contents of histamine and tyramine among biogenic amines decreased to 35.85 and 41.04 mg/kg, respectively. Finally, a soy bean and rice bran mixing ratio of 9:1 was determined to be the optimal mixing ratio in the sensory evaluation.