• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.287-293
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• 2014

The physicochemical characteristics of 4 domestic wheat flour products were compared to those of 4 imported wheat flour products marketed in Korea. The contents of moisture, ash, protein, total dietary fiber (TDF), color (L, a, b), whiteness, solvent retention capacity (SRC), water absorption index (WAI), water soluble index (WSI), pasting characteristics by rapid visco analyzer (RVA), and principle component analysis (PCA) were analyzed. The domestic wheat flour products were composed of higher content in ash and protein, compared to the imported wheat flour products. The domestic wheat flour products had lower SRC and WSI characteristics than the imported wheat flour products. The values of lactic acid SRC (LASRC) in the imported wheat flour products showed an increasing trend as the protein content increased. The differences in viscosity were observed in the domestic wheat flour products. However, no major significant differences of viscosity were found among the imported wheat flour products. The result of PCA showed a consistent trend in the imported wheat flour (strong, medium, and weak), while a consistent trend was not shown in the domestic wheat flour products. Therefore, further research is needed to standardize the different types of domestic wheat flour products.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.241-249
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• 1998

The purpose of this study was to develop a recipe for high quality Yackwa (fried cake made of wheat flour) by adjusting the mixing ratio of flours, frying temperature and time. Yackwas were prepared by using 3 kinds of flour mix (3：7, 4：6, and 2：8 of weak to medium ratio), fried at various temperatures and times, and evaluated by mechanical characteristics and sensory evaluation. It was found that Yackwa prepared with 3：7 mixing ratio of flour and fried at 160$^{\circ}C$ for 9 min was most preferred. Yackwas with the same flour mixing ratio and fried at 150-155$^{\circ}C$ for 12∼16 min were also within the range of acceptance. The characteristics of desirable Yackwa were suggested to be soft, crispy, and to have little taste of oil.

• Korean Journal of Microbiology
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• v.29 no.2
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• pp.136-142
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• 1991

The selection of ethanol-tolerant strains was applied to enrichment culture of YPD broth medium containing various concentrations of ethanol. Isolates were identified to be Saccharomyces cerevisiae, the others as S. dairensis, S. exiguus, S. telluris, Saccharomycodes ludwigii, Schwanniomyces occidentalis var. occidentalis and Zygosaccharomyces florentinus. Among isolates S. cerevisiae YO-1 was screened as having the highest ethanol tolerance and produced 18% (v/v) ethanol after 4 days fermentation. The change of fatty-acyl residues represents that a progressive decrease in fatty-acyl unsaturation and a proportional increase in saturation in phospholipids of yeast cells during fermentation affected the yeast viability. Supplementation ethanol to the cultures led to an increase of unsaturated fatty-acyl residues, especially $C_{16}$ or $C_{18}$ residues, along with a decrease in the proportion of saturated residues in cellular phospholipids. Increasing the amount of soy flour led to an increase in the maximum number of viable yeast cells and ethanol production. It was possible in 4 days to reach 21% (v/v) ethanol by adding 4% soy flour as source of unsaturated fatty-acyl residues to the fermentation medium. Soy flour not only increased yeast population but also enhanced the physiological properties of yeast cells to be ethanol tolerant in the anaerobic culture.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.979-983
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• 1993

A power operated (0.5 hp electric motor) grain flour separator was designed and developed for separation of grain (wheat, corn, chickpea and soybean) flour it no various fractions based on the size of the particles of the product. The separator is made of mild steel and consists of a hopper, power driven agitating mechanism, feed control , cylindrical separator unit and an eccentric mechanism. The machine was tested for wheat (variety : Subjata) flour separation into four fraction, viz : semolina ; Gr-I and II, flour (coarse) and white (fine) flour. Wheat samples (6.8% m.c., db) were first pearled by CIAE pearler for 15.8% bran removal . The product and machine characteristics were determined at different capacities varying from 24 kg/h to 143 kg/h. It was found that 76 kg/h capacity gave reasonably best results in terms of purity and recovery of semolina vis-a-vis the market product. The energy requirement of the machine at no-load was found to be 230 w and at load conditio s, it varied between 36.3-6.4kj per kg of feed separation. The machine could be used by small flour millers, small/medium size traders and retailers and other processors for making available various flour products of different particle size in the market for ready use fo the consumers.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.234-237
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• 2008

The quality of sugar-snap cookie prepared with wheat flour supplemented with black rice flour was investigated. The pH of cookie batter decreased as the amount of black rice flour increased. Increasing proportions of black rice flour resulted in increase of width and spread factor of cookie, whereas thickness and fracturability decreased. L, a, and b values decreased as the amount of black rice flour increased. Sensory evaluation showed that supplements of 20, 25, and 20% black rice flour had the best overall preference in strong, medium, and weak flours, respectively.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.835-843
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• 2010

The objectives of this study were to investigate the effect of fermentation medium on the hydroxyl radical scavenging activity of exopolysaccharides from Inonotus obliquus by response surface methodology (RSM). A two-level fractional factorial design was used to evaluate the effect of different components of the medium. Corn flour, peptone, and $KH_2PO_4$ were important factors significantly affecting hydroxyl radical scavenging activity. These selected variables were subsequently optimized using path of steepest ascent (descent), a central composite design, and response surface analysis. The optimal medium composition was (% w/v): corn flour 5.30, peptone 0.32, $KH_2PO_4$ 0.26, $MgSO_4$ 0.02, and $CaCl_2$ 0.01. Under the optimal condition, the hydroxyl radical scavenging rate (49.4%) was much higher than that using either basal fermentation medium (10.2%) and single variable optimization of fermentation medium (35.5%). The main monosaccharides components of the RSM optimized polysaccharides are rhamnose, arabinose, xylose, mannose, glucose, and galactose with molar proportion at 1.45%, 3.63%, 2.17%, 15.94%, 50.00%, and 26.81%.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.45-50
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• 2008

This study was carried out to investigate the promoting effect of wood flour on the mycelial growth of Lentinus lepideus and Lentinus edodes. To determine the optimal culture condition, we first examined the tissue origin of pine flour (Pinus densiflora) including needle, bark, root and xylem. Only the xylem-derived flour increased mycelial growth compared to no treatment control. The addition of the xylem flour (5 g/l) showed the highest increase and the glucose level in the basal medium was best at 10 g/l. The smaller particle size of the xylem flour showed the positive effect on mycelial growth; two-fold increase when supplemented with flour of which particle size is less than $106\;{\mu}m$ in diameter compared to $425\;{\mu}m$. The addition of the xylem flour continuously increased the mycelial production for 25 days while mycelia stopped growing within 15 days without the xylem flour. In addition, when woody flour obtained from the different tree species was applied to L. edodes mycelial culture, all treatments accelerated mycelial production compared to the control. Based on all results described above, we conclude that the supplementation of woody flour to culture medium may be an another promising way to increase mycelial production of economically important fungi.

• KSBB Journal
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• v.24 no.1
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• pp.30-40
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• 2009

Statistical optimization of the production medium was carried out in order to find an optimal medium composition in itaconic acid fermentation process. Itaconic acid utilized in the manufacture of various synthetic resins is a dicarboxylic acid biosynthesized by fungal cells of Aspergillus terreus in a branch of the TCA cycle via decarboxylation of cis-aconitate. Through OFAT (one factor at a time) experiments, six components (glucose, fructose, sucrose, soluble starch, soybean meal and cottonseed flour) were found to have significant effects on itaconic production among various carbon- and nitrogen-sources. Hence, using these six factors, interactive effects were investigated via fractional factorial design, showing that the initial concentrations of sucrose and cottonseed flour should be high for enhanced production of itaconic acid. Furthermore, through full factorial design (FFD) experiments, negative effects of $KH_2PO_4$ and $MgSO_4$ on itaconic acid biosynthesis were demonstrated, when excess amounts of the each component were initially added. Based on the FFD analysis, further statistical experiments were conducted along the steepest ascent path, followed by response surface method (RSM) in order to obtain optimal concentrations of the constituent nutrients. As a result, optimized concentrations of sucrose and cottonseed flour were found to be 90.4g/L and 53.8g/L respectively, with the corresponding production level of itaconic acid to be 4.36 g/L (about 7 fold higher productivity as compared to the previous production medium). From these experimental results, it was assumed that optimum ratio of the constituent carbon (sucrose) and nitrogen (cottonseed flour) sources was one of the most important factors for the enhanced production of itaconic acid.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1338-1346
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• 2006

Ansamitocin P-3 is a potent antitumor agent produced by A. pretiosum. A deletion mutant of A. pretiosum was constructed by deleting the asm2 gene, a putative transcriptional repressor. The deletion mutant showed a 9-fold enhanced ansamitocin P-3 productivity. The response surface method with central composite design was employed to further optimize the culture medium composition for ansamitocin P-3 production by the deletion mutant. The concentrations of four medium ingredients, dextrin, maltose, cotton seed flour, and yeast extract, which have been reported as major components for ansamitocin production, were optimized through a series of flask culture experiments. The optimum concentrations of the selected factors were found to be dextrin 6.0%; maltose 3.0%; cotton seed flour 0.53%; and yeast extract 0.45%. The maximum titer of ansamitocin P-3 was 78.3 mg/l with the optimized composition, about 15-folds higher than the unoptimized titer of 5.0 mg/l obtained with YMG medium.

• The Korean Journal of Mycology
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• v.21 no.3
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• pp.212-216
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• 1993

Agricultural and forest wastes were tested as substrate for the production of Flammulina velutipes. Among the meranti, pine tree, mixed sawdust, coffee waste and peanut hull tested, coffee waste was the best basal substrate for the production of basidiocarps. When various supplements, such as ricebran, brewer's grain, defatted corn flour, defatted soybean flour and defatted rapeseed flour were tested, defatted corn flour was chosen for the production of basidiocarps. Maximum yield of basidiocarps(129.38 g/bottle) was obtained from the mixed medium at 4 : 1 ratio of coffee waste and defatted corn flour.