• Food Science of Animal Resources
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• v.29 no.5
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• pp.573-578
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• 2009

This study examined the effect of gamma irradiation on shelf-life extension and sensory characteristics of dak-galbi. Commercial dak-galbi sauce was gamma-irradiated at 0, 5, 10, 15, 20, 25, and 30 kGy. The dak-galbi sauce (200 g) was then added to diced chicken (800 g) for cooking, and the cooked dak-galbi samples in vacuum bags were stored at $35^{\circ}C$ for 5 d. Dak-galbi samples were analyzed on d 0, 1, 2, 3, 4, and 5 for microbial analysis (plate count agar), thiobarbituric acid (TBARS) and volatile basic nitrogen (VBN) measurements, and on d 0 for sensory evaluation. On d 0, total bacterial populations were below detection limit after dak-galbi marinated with the gamma-irradiated (${\geq}15\;kGy$) sauces were cooked, and the samples marinated with higher dose irradiated dak-galbi sauce had lower (p<0.05) bacterial populations during storage. TBARS values of the dak-galbi samples marinated with non-irradiated sauce were not different ($p{\geq}0.05$) with those marinated with irradiated sauces on d 0, and the TBARS values increased (p<0.05) during storage at $35^{\circ}C$, regardless of irradiation dose. In the VBN analysis, there was no difference ($p{\geq}0.05$) in VBN values among irradiation doses on d 0, but VBN values decreased (p<0.05) as irradiation dose increased during storage. Moreover, there were no significant differences ($p{\geq}0.05$) in sensory characteristics among irradiation doses. These results indicate that use of gamma irradiation on dak-galbi sauce may be useful in shelf-life extension without compromising the sensory characteristics of dak-galbi.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.319-325
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• 1999

A culture-dependent survey of bacterial community in the soil-root system of red pepper and tomato was conducted by dilution plate count method. The bacterial community within soil was not different from that of rhizoplane. However, the populations of fluorescent, pseudomonads were higher in rhizoplanes than in soils and higher in healthy rhizoplanes than in Phytophthora disease-infested rhizoplanes. The bacterial community of the pepper cropped soil and rhizoplanes was very similar to that of the tomato-cropped soil and rhizoplanes. Among 285 identified bacterial colonies, most colonies were belong to two groups by fatty acid analyses: 52% of the 285 colonies were belong to low G + C gram positive bacteria group. Bacillus spp. and 33% were belong to high G + C gram positive bacteria group. In order to use beneficial microorganisms to agro-ecosystem, these data of field trials should be intensively accumulated.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.301-305
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• 2016

This study was conducted to investigate changes in pH, volatile basic nitrogen (VBN), thiobarbituric acid (TBA), $a^*$ (redness), shearing force, and microbial content (total plate count; TPC) in beef during freezing storage at -1, -5, and $-20^{\circ}C$ for 21 days. TPC as an effective quality indicator was used to identify the decay point by regression analysis. The pH, TBA values, and TPC significantly increased with storage at all tested temperatures (p<0.05). VBN significantly increased and shearing force significantly decreased with storage at -1 and $-5^{\circ}C$ (p<0.05). TPC showed significant correlation with temperature at $-1^{\circ}C\;(R^2=0.891)$, $-5^{\circ}C\;(R^2=0.856)$, and $-20^{\circ}C\;(R^2=0.444)$. The decay points at -1, -5, and $-20^{\circ}C$, were 27, 52, and 84 days, respectively. The results suggest that a freezing temperature of $-5^{\circ}C$ is effective for short-term storage of beef.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.133-139
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• 2011

In this study, we determined the changes in microbial numbers in solar salts according to the manufacturing process and storage duration. The salt samples were harvested from salt farms in Shinan (area 2) and Yeonggwang (area 1). They were serially diluted ten-fold and then placed on 4 kinds of cultivable media (mannitol salt agar, eosin methylene blue, plate count agar, and trypticase soy agar). After incubation, we obtained 62 halophilic isolates from the salt samples. Coliform and general bacteria were not detected in all salt samples. By 16S rRNA sequencing analysis, we found 12 kinds of halophilic bacteria belonging to the genera Halobacillus, Halomonas, Bacillus, Idiomarina, Marinobacter, Pseudoalteromonas, Vibrio, Salinivibrio, Virgibacillus, Alteromonas, Staphylococcus and some un-known stains. In our study, we discovered two novel species that have a 16S rDNA sequence similarity below 97%.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• Korean journal of food and cookery science
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• v.18 no.3
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• pp.290-299
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• 2002

An optional ingredient Perilla Seed paste was adopted to improve the quality of Yulmoo Mul-kimchi during fermentation. The final weight percentage of perilla seed paste in Yulmoo Mul-kimchi was adjusted to 0, 10, 20, 30, and 40% per water respectively. Chemical and sensory characteristics were determined during fermentation at 10$\^{C}$ for 25 days. The effect was varied depending on the amounts of perilla seed paste, but Yulmoo Mul-kimchi fermented with 20% perilla seed paste was most favored for color, smell, sour taste, carbonated taste, texture and overall acceptability in the sensory evaluation. The pH decreased with the increase of total acidity. The total vitamin C content increased initially to the certain level at a certain time of fermentation depending on the level of perilla seed paste, and then decreased later. In case of reducing sugar, the 20% treatment showed the highest content. Turbidity values were generally increased in all samples during fermentation, even though the extents were limited. Total plate count and the number of lactic acid bacteria were gradually increased and then decreased showing the maximum microbial counts during fermentation. The optimum levels of perilla seed paste in Yulmoo Mul-kimchi obtained through experiments were between 20 and 30% of added water content, preferably 20% for color, fermentation-retarding effect, and sensory taste of the product.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.10
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• pp.1437-1449
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• 2006

Thirty six pre-weaned Barbari kids at 4 months age were reared on four rations computed using coarse cereal grains and by-products of pulses and oil seeds with Crude Protein (CP) and Total Digestible Nutrients (TDN) of 12 and 55% (Low protein Low energy); 12 and 60% (Low protein High energy); 14 and 55% (High protein Low energy); and 14 and 60% (High protein High energy), respectively. After 180 days on feed, male animals ($4{\times}5=20$) were slaughtered to study the effect of diet on carcass characteristics and meat quality. To asses the effect, if any, of such diet on product quality, meat balls were prepared and evaluated for quality changes when fresh as well as during storage ($-20{\pm}1^{\circ}C$). Feeding a ration with CP12 and TDN 60% (LH) to kids produced animals with highest slaughter weight (20.3 kg) yielding higher carcass weight and dressing percentage, lean (65.6%) and fat (6.6%) contents with low bone and trim losses. Although total variety meat yield was markedly higher in HL, the non-carcass fat deposition was relatively higher in LH carcasses. The water activity ($a_w$) of fresh goat meat ranged from 0.994-0.995 and total cholesterol 72.8-90.5 mg/100 g meat. The pH was high in HL and HH meat resulting in decreased ($p{\leq}0.05$) extract release volume (ERV). Meat balls were prepared using meat obtained from goats fed different rations (treatments) and stored at $-20{\pm}1^{\circ}C$. They were evaluated on day 0 and months 1, 2, 3, 4 for physicochemical, microbiological and organoleptic changes. Overall moisture (%), $a_w$, TBA number and pH value were 67.9, 0.987, 0.17, 6.6 respectively and were not affected by treatments except pH that was significantly ($p{\leq}0.01$) lower on LH. As the storage period advanced moisture, pH, $a_w$ and TBA number increased irrespective of treatments. Feeding various diets had no marked effect on microbial load of meat balls but with increasing storage period Standard Plate Count (SPC) and psychrotrophs declined ($p{\leq}0.01$). Treatment LL and LH produced meat balls with better flavour.

• Applied Biological Chemistry
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• v.26 no.1
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• pp.35-40
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• 1983

The inhibitory activity of 20 Lactic strains from Kimchi was tested against Escherichia coli and other microorganisms. Of the lactic strains investigated, A7 (Pediococcus cerevisiae) and C4(Leuconostoc spp.) were the most effective in restricting the growth of test organisms. The mixed culture inoculation of each selected lactic strain and Escherichia coli resulted in a drastic reduction in the plate count of Escherichia coli after 24 hours. Similar results were obtained when Staphylococcus aureus and Bacillus cereus were used as test organisms. For all test organisms, the presence of A7 caused a higher death rate constant than that of C4. Addition of catalase in the mixed culture did not prevent inhibition, suggesting that hydrogen peroxide did not cause the inhibition. The filtrate of A7 culture added to Escherichia coli showed identical inhibitory action, however heat treatment of filtrate at $80^{\circ}C$ 30min. destroyed the inhibitory activity. A7 filtrate treated with trypsin substantially lost the inhibitory effect, but not by pepsin. The results imply that the protein-like compound(s) is the principal inhibitor produced by this lactic strain.

• Culinary science and hospitality research
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• v.18 no.2
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• pp.182-196
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• 2012

This study investigates the optimal application of perilla leaves to fresh noodles in terms of a variety of beneficial effects and functions such as the anti-microbial function of the leaves. First, we measured the water contents of the fresh noodles and found that the ones added with 7% lyophilized perilla leaf extract showed the maximum water contents whereas the control noodles without perilla leaf extract the minimum. Increasing amount of raw perilla leaf extract or lysophilzed perilla leaves in the fresh noodles elevated the L value and significantly reduced the A value. The mass and volume of the fresh noodles were gradually decreased with raw perilla leaves added. Addition of raw perilla leaf extract and lyophilized perilla leaves decreased the turbidity of the fresh noodles. Hardness of the fresh noodles was increased by the addition of lyophilized Perilla leaves. Next, we tested the effect of the addition of sesame leaves on microbial growth. No microbes were found in the fresh noodles in the absence or presence of sesame leaves at day 0. When the noodles were stored for 3 days, the greatest number of bacteria was detected in the noodles without perilla leaves while addition of perilla leaves lowered the amount of bacteria in the noodles. We then performed the sensory test. For the raw perilla leaf extract addition, the noodles with 9% of extract exhibited the highest in appearance, flavor, color (6.47), texture (6.60), and overall acceptability (7.67). Texture was the highest in the ones with 3% (6.87) and 5% (6.20) of extracts added. Overall acceptability (7.07) was the best when 3% perilla leaves were added. Overall, 9% addition of raw perilla leaf extract or 3% addition of lysophilized perilla leaves showed optimal tastes.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.360-366
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• 2010

Doenjang (fermented soybean paste) is one of the korean traditional fermented soybean product which is consumed with cooked rice as a soup or paste. During the fermentation, soybean protein hydrolyzed into amino acids and various peptide, and various organic acids by mirobes related and enzymes produced by meju fermentation. Some commercial products locationally samples give more sour taste than normal due to abnormal fermentation which the reasons are not clear. Three samples that gave sour taste organoleptically were collected and analyzed their characteristics such as pH, moisture content, acidity and microbial counts. The pH of the sour sample were lower than the normal with higher acidity as pH 5.39 (normal) to pH 4.36 (S2) and 15.80 ml of(0.lN NaOH consumed) to 21.80 ml (S1) respectively. Salt and moisture contents were different with sour and normal Doenjang as 16.38% (normal) to 8.92% (S3) in salt and 55.94% (normal) to 49.34% (S1) in moisture content. Total viable counts were $4.1{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2), and $3.4{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2) in acid producing microbes at BCP plate. Yeast and mold were not detected. The composition of acids as mainly lactic acid and acetic acid of sour Doenjang. Total free amino acids content were lower the sour Doenjang than the normal.