• Culinary science and hospitality research
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• v.14 no.1
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• pp.161-169
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• 2008

This study was performed to find out the quality characteristics of rice noodles by addition of red ginseng(0, 2, 6, 10%). The quality characteristics of the sample were estimated in terms of general composition, growth of microorganism and sensory evaluation. The results from this study were as follows. The protein, lipid and ash contents did not show significant difference in any of the groups. In dry rice noodles, moisture content significantly decreased in red ginseng groups but, in half-cooked rice noodles, moisture content significantly increased in 6 % and 10% red ginseng added groups(p<0.05). The microbial count showed less growth in red ginseng added groups after 3 months(p<0.05). According to sensory evaluation, surface color proved very good in the 10% red ginseng added group among the training panel while very good in the 2% red ginseng added group among consumers. Flavor was good in red ginseng added groups(p<0.05). Taste was very good in the 3% red ginseng added group. Appearance and overall quality were highest in the 2% and 6% red ginseng added groups(p<0.05). Therefore, rice noodles containing 2% or 6% red ginseng were most preferable and safe during 5 months and 6 days in dry and half-cooked noodles respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.563-570
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• 1997

Volatile flavor components in the mash of takjus prepared by using different nuruks such as Mucor racemosus nuruk, Rhizopus japonicus nuruk, Aspergillus oryzae nuruk, Aspergillus kawachii nuruk and nuruk (Korean-style bran koji), were identified by using GC and GC-MS. Twenty alcohols, 26 esters, 10 acids, 10 aldehydes and 6 others were found in the mash of takju after 16 days of fermentation. Takju by Aspergillus oryzae nuruk had the most various components of volatile flavor. Fifty-four flavor components including ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 1-hexanol, 2,3-butadienol (D,L), benzeneethanol, acetic acid ethyl ester, succinic acid diethyl ester, butanoic acid monoethyl ester, acetic acid and benzene acetic acid 4-acetyloxy-3-methyl ethyl ester were usually detected in all the treatments. The relative peak area of volatile components was as follows: alcohol $(71.28{\sim}90.23%)$, ester $(0.66{\sim}9.05%)$, acid $(0.2{\sim}0.6%)$ and aldehyde $(0.02{\sim}0.09%)$. Specially, 1-pentanol and hexanoic acid ethyl ester were high in takju made of nuruk (Korean-style bran koji). 1-Hexanol, 1-dodecanol, acetic acid and 1,2-benzene-dicarboxylic acid diprophenyl ester were high in takju made of Mucor racemosus nuruk. 4-Acetyloxy, 3-methyl benzeneacetic acid phenyl ester, 2-methyl-1-propanol, 3-methyl-1-butanol, succinic acid diethylester, butanoic acid monoethyl ester and butanoic acid were higher content in takju by Rhizopus japonicus nuruk. Acetic acid ethyl ester, pentanoic acid and 3-methyl butanoic acid were high in takju that was made of Aspergillus oryzae nuruk. 1-Butanol was high in takju by Aspergillus kawachii nuruk.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.287-294
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• 2007

Effect of combined use of anti-microbial materials, such as ethanol, mustard and chitosan, on the quality of low salted kochujang was investigated during fermentation at $20^{\circ}C$ for 12 weeks. Viable cells of yeast increased remarkably during fermentation, but increasing ratio was significantly low in ethanol-mustard added kochujang. Activity of ${\beta}-amylase$ was high in anti-microbial material added kochujang, whereas ${\alpha}-amylase$ and protease activities were low in those groups. Water activity decreased during fermentation with being low in the control kochujang prepared with normal-salt without anti-microbial materials. Hunter L-, a- and b-values of kochujang increased during fermentation, and the degree of increase in total color difference $({\Delta}E)$ was low in ethanol added kochujang. Titratable acidity of kochujang was decreased in anti-microbial materials added group at late aging period, and oxidation-reduction potential was low in the control kochujang. Total sugar and reducing sugar contents of kochujang were high in ethanol-mustard added kochujang. Ethanol contents of kochujang increased at late aging period, with high values in ethanol-chitosan added kochujang. Amino nitrogen content increased during middle of fermentation, and ammonia nitrogen content of kochujang decreased in ethanol-mustard-chitosan added group during fermentation. After 12 weeks fermentation, sensory results showed that ethanol or ethanol-mustard added kochujang were the highest in color and flavor with the highest overall acceptability.

• Food Science of Animal Resources
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• v.35 no.4
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• pp.449-458
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• 2015

The effects of quality grade and storage time on physicochemical, sensory properties and microbial population of Hanwoo striploin beef were investigated. After a total of 30 Hanwoo beef were slaughtered, the cold carcasses were graded by official meat grader at 24 h postmortem. The carcasses were categorized into five groups (quality grade 1++, 1+, 1, 2, and 3) and were vacuum-packaged and stored. The samples were kept for 1, 4, 6, 8, 11, 13, 15, 18, 20, 22 and 25 d for analyses. As the quality grade was increased, moisture, protein and ash contents decreased (p<0.05). Higher quality grade corresponded with higher fat contents. The shear force values decreased with increasing quality grade and showed decreases sharply during the first 4 d (p<0.05). pH, water holding capacity, cooking loss, and volatile basic nitrogen for grade 1++ groups were lower than for grade 3 (p<0.05). CIE L* and b* values increased as increased quality grade (p<0.05). Meat color decreased until 13 d and fluctuated after 15 d of storage (p<0.05). Regarding the sensory scores, higher quality grade corresponded with higher juiciness, tenderness, flavor, fatty and palatability scores (p<0.05). Generally, increased storage time for 15 d improved sensory scores attributes. Results indicate that a high quality grade could positively influence physicochemical and sensory properties.

• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.17-22
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• 1978

The microbial and chemical changes, and characterization of the predominant acid-producing bacteria in the fermenting pig feces blended with corn meal at a ratio of 50：50 were studied. The fermentation was dominated by lactobacilli, which multiplied rapidly for the first 24 hours. The acid produced during the fermentation caused rapid pH drop to pH 4.5 and halted the growth of E. coli and yeast. The initial acid producing bacteria in the mixture was predominantly Streptococcus species, which were reduced in number rapidly. After 7 days of fermentation, three lactobacilli species were appeared L. acidophilus, L. fermenti, L. delbrueckii. Chemical changes during the fermentation were also studied. The lactic acid fermentation imparted a good tangy acid flavor to the corn-feces mixture by removing or covering the .fecal ordour and made the corn-feces mixture palatable for the animal as well as halted the unwanted microbial flora. We hope the lactic acid fermentation will replace the heat processing in the utilization of animal feces.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.746-750
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• 1999

The effects of electron-beam irradiation on the microbial and sensory qualities of pork loins were studied. The pork loins were aerobically packed in polyethylene films and exposed to absorbed doses of electron-beam at 0, 0.5, 1 and 2 kGy in ambient temperature. All samples were stored at $4{\pm}1^{\circ}C$. As an irradiation dose increased, decontaminating effects increased in terms of total microbial count, lactic acid bacteria and psychrotrophs during storage. All difference degrees in the triangle test were very low levels. In the descriptive analysis, Low dose irradiation did not affect aroma, off-flavor and acceptability in fresh and cooked meats.

• Food Science of Animal Resources
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• v.36 no.2
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• pp.215-222
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• 2016

The combined effects of irradiation and aging temperature on the microbial and chemical quality of beef loin were investigated. The samples were vacuum-packaged, irradiated at 0 or 2 kGy using electron-beam (EB), and stored for 10 d at different aging temperatures (2, 14, or 25℃). The microbial growth, shear values, meat color, and nucleotide-related flavor compounds of the samples were analyzed. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and Escherhia coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose. Irradiation reduced the total aerobic bacteria (TAB) over the storage, but higher aging temperature increased the TBA. Thus TAB increased sharply in non-irradiated and high temperature-aged (14, 25℃) beef samples after 5 d. With increasing aging temperature and aging time, shear force values decreased. Lipid oxidation could be reduced by short aging time at low aging temperature. The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the aging period. As aging period and temperature increased, IMP decreased and hypoxanthine increased. Considering microbial and physicochemical properties, irradiation can be used for raw beef to be aged at relatively high temperature to shorten aging time and cost.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.636-641
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• 2006

Jeolpyun with different amounts of added ramie (Ramie Jeolpyun) was prepared and the quality characteristics were examined. Texture profile analysis, Hunters color and total microbial counts were carried out during storage for 4 days. Sensory evaluation was carried out during storage for 2 days. The L value of Jeolpyun with 0% added ramie was one of the highest in the sample and increased with increasing storage time. In texture profile analysis, hardness, chewiness, gumminess were increased with increasing storage time. The hardness of Ramie Jeolpyun with 80% added ramie was one of the lowest in the samples. The total microbial counts of Ramie Jeolpyun were increased during storage. The results of sensory evaluation showed that Ramie Jeolpyun with 60% and 80% added ramie had a high score in color, flavor and softness.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1736-1743
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• 2017

Sourdough is made by fermentation of dough by lactic acid bacteria (LAB) and yeast to improve bread properties like volume, flavor, and texture. A Korean traditional sourdough was made by fermenting rice flour with rice wine (makgeolli) and used to make sponge-like bread (jeung-pyun). The aim of this study was to investigate the microbial diversity of makgeolli products and their influence on the organoleptic quality of jeung-pyun. Three commercial makgeolli were tested for jeung-pyun production, with each product exhibiting varied dough swelling rates and organoleptic qualities, and among them, J-product was ranked highest in texture and taste. Microbial analysis of the three makgeolli also showed a big difference in their population and diversity. J-product had the highest LAB and yeast counts, and the predominant species were Lactobacillus casei, Lactobacillus brevis, Leuconostoc pseudomenteroides, and Saccharomyces cerevisiae. Using J-product, sourdough was fermented at $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$, and the microbial growth in and textural properties of jeung-pyun were examined by instrumental and sensory tests. At high temperature ($35^{\circ}C$), the rates of dough swelling and acidification were fast due to rapid microbial growth mainly caused by LAB, resulting in a short leavening time and soft and sour jeung-pyun. Sensory tests showed consumer preference for the soft and mild-sour jeung-pyun. This study shows that LAB in makgeolli play key roles in production of jeung-pyun, influencing the textural and sensory properties. For the production of high-quality jeung-pyun, development of LAB starters with high gas productivity and low acidity and establishment of an optimal fermentation procedure for rice dough are necessary.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.103-108
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• 2022

This study investigated the strains and fermentation characteristics of used to ferment a mixture of rice and soybeans to manufacture low-salt doenjang for flavoring. The soybean and rice mixture was fermented using three selected strains of Aapergillus oryzae and Bacillus sp. The changes in quality of the fermented products were found to be dependent on the aging period. Therefore, the strain and a suitable aging period were seleted based on the increases in AN, total sugar, and reducing sugar. The fermented products were prepared and mixed, using the selected or commercially available strains (the sample and control, respectively), to create low-salt doenjang. Following this, their characteristics were compared. The sample had a higher content of taste-related ingredients(free amino acid, nucleic acid-related substances) than the control. Using the selected strain to ferment a rice and soybean mixture will thus be expected to enhance the flavor of industrially produced seasoned doenjang.