• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1596-1603
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• 1999

Dongchimi (Korean-style fermented radish with juice) products were frozen to prevent further acidification and softening of texture by restraining microbial growth and enzyme activity during storage. Dongchimi juice and radish were separated prior to freezing process. Dongchimi radish was frozen at $-20^{\circ}C,\;-70^{\circ}C$ and immersed in liquid nitrogen and dongchimi juice was frozen at $-20^{\circ}C\;and\;-70^{\circ}C$. Frozen dongchimi samples were thawed with ambient temperatures of $4^{\circ}C\;and\;27^{\circ}C$ and with 915 MHz-microwave, respectively. Dongchimi radish immersed in liquid nitrogen and thawed with 915 MHz-microwave showed the highest pectinesterase activity and hardness, and the lowest polygalacturonase activity and color change, indicating that this quick freezing-quick thawing method can be used for the long-term storage of dongchimi products. Dongchimi juice frozen at $-70^{\circ}C$ and thawed with 915 MHz-microwave retained its pH and titrable acidity, and showed a largest reduction in total aerobic count and lactic acid bacteria.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.671-679
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• 2003

Effects of sun-dried, refined, seaweed, and bamboo salts on the quality of kochujang were studied by measuring enzymatic, microbial, and physicochemical characteristics of kochujang during 12 weeks of fermentation. Yeast count was low in the bamboo-salt kochujang, whereas that of aerobic bacteria was low in the seaweed-salt kochujang. Acid protease activity was high in the bamboo-salt kochujang, whereas amylase activity did not show any remarkable difference. Color change was lowest in the bamboo-salt kochujang. Water activities of all kochujangs decreased during fermentation with the lowest shown in the refined-salt kochujang. Consistency of seaweed-salt kochujang was the highest. Total sugar content was higher, whereas ORP was lower in the seaweed- and bamboo-salt kochujangs. Titratable acidity changed slightly in the bamboo-salt kochujang. Reducing sugar content was the lowest, whereas ethanol content was the highest in the refined-salt kochujang. Amino and ammonia nitrogen contents of kochujangs increased up to the middle of fermentation period then decreased with lower changes observed in the sun-dried and refined-salt kochujangs. Results of sensory evaluation indicated that the bamboo-salt kochujang was more acceptable than the sun-dried salt kochujang in taste, color, and overall acceptabilities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1050-1057
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• 1997

Microbial counts, enzyme activities and taste components of traditional kochujangs prepared with the powders from 4 different varieties of red pepper, were investigated during 90 days fermentation for the industrial production of traditional kochujang. The viable cell counts of anaerobic bacteria in kochujangs did not change remarkably during fermentation, however, aerobic bacterial counts showed a rapid increase up to 90 days of aging. The yeasts in all kochujang samples increased until 60 days of aging and than decreased. After 90 days of aging, the count of aerobic bacteria in Kumtop kochujang was higher than those of others. The activities of liquefying amylase decreased during the aging, but those of saccharogenic amylase increased at 60 days of aging. The activities of neutral protease were higher than those of acidic protease, and increased during the middle and last period of aging. The major free sugars of kochujang were maltose and glucose, and their contents were higher in Hongkwang kochujang. The major organic acids of kochujang were succinic, formic and citric acid, followed by lactic acid. Succinic acid content in kochujang decreased during fermentation, whereas formic and citirc acids were increased. The major free amino acids were serine, proline, glutamic acid, aspartic acid and alanine. Kumtop kochujang contained the highest amount of total free amino acids. Among the nucleotides and related components in kochujang, cytidine-5-monophosphate was the most abundant component at the begining of aging period, while hypoxanthine increased remarkably during fermentation. Hanwang kochujang was higher in the content of nucleotides than others. Capsaicin contents of kochujang decreased during aging and those of Jangter kochujang was higher than that of others. Sensory evaluation showed that Jangter kochujang was significantly better than Kumtop kochujang in overall acceptability, but there were no appreciable differences in color and flavor.

• Food Science and Preservation
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• v.11 no.1
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• pp.1-6
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• 2004

The mixture of botanical antimicrobial agent-citurs product and ginseng extract mixture(BAACG) was applied to garlic stalk or pork cooked in soysauce to extend their selflife. BAACG showed a remarkable antimicrobial activity against a wide spectrum of food-borne infection microorganisms and thermal and pH stability. In comparison with scanning electron microscopic photos of microbial cells not-treated and treated with BAACG the physiological cytomembrane function of BAACG-treated microorganisms was destroyed and the dead cell numbers was increased. The quality of garlic stalk or pork cooked in soysauce was controlled by the addition of BAACG in their raw materials. BAACG-treated garlic stalk or pork cookeries showed considerably to decrease the numbers of total cell count and expressed no odor and no sticky state appeared in the control. BAACG was expected to be a preservative agent which could be applied to raw or processed food stuffs in the view of food safety.

• Animal Bioscience
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• v.34 no.12
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• pp.1951-1962
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• 2021

Objective: This study was conducted to evaluate single cell protein (SCP), produced from Methylococcus species, as a protein source on the growth performance, carcass traits and gut health of broiler chickens. Methods: Ten iso-nitrogenous and iso-caloric diets containing 0 (Control), 2.5%, 5%, 7.5%, and 10% SCP replacing either soybean meal (T₁ to T₅) or fish meal (T₆ to T₁₀) were formulated. Each diet prepared for starter (0 to 14 days), grower (15 to 21 days), and finisher (22 to 42 days) phases was offered to four replicates of 10 chicks each (n = 400). Growth performance at different phases and carcass characteristics and intestinal morphology on 42nd day of trial were measured. Results: Body weight gain in groups fed 2.5% and 5% SCP diets were comparable to control during different phases and cumulatively, however lower (p<0.01) in 7.5% and 10% SCP diets. Feed conversion ratio was better (p<0.01) in 2.5% and 5% SCP diets. Dressing percentage, abdominal fat percentage and meat:bone ratio were not affected (p>0.05) by SCP inclusion in the diets. However, breast percentage was higher (p<0.01) in 2.5% and 5% SCP groups and thigh percentage higher in 7.5% and 10% SCP groups. Total microbial count in duodenum, jejunum and ileum were not affected (p>0.05) by SCP inclusion up to 10% in diets. Duodenal villi length and crypt depth were highest (p<0.01) in group fed 5% SCP diets and lowest in group fed 10% SCP diets. Jejunal villi length and crypt depth as well as ileal villi length were lowest (p<0.01) in group fed 10% SCP diets. Body weight gain, feed consumption, feed conversion ratio and gut health were better (p<0.01) in broilers fed fish meal based diets compared to soybean meal based diets. Conclusion: It was concluded that inclusion of SCP up to 5% replacing soybean meal in broiler diets is beneficial in improving growth rate, breast yield and gut health status.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.2
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• pp.91-100
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• 2024

Packaging method and storage time play a significant role in maintaining the quality, safety, and shelf-life of food. In this study, the quality such as acid value, peroxide value, total bacterial count, color difference, and flavor of Marsupenaeus japonicus Oranda was evaluated depending on the five packaging methods (T-N, P-N, P-O₂R, P-V, and P-N₂) and storage periods. Changes of acid value and peroxide value strongly depend on the existing oxygen of headspace in the Marsupenaeus japonicus Oranda packages. Regardless of packaging methods, the change in acid value, peroxide value, microbial growth and flavor of the Marsupenaeus japonicus Oranda occurred depending on the storage time. Especially, it is identified the quality changes of Marsupenaeus japonicus Oranda stored with P-N₂ package with less oxygen contents were retarded, compared to the them with T-N packaged with high oxygen contents.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.375-379
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• 2016

Atmospheric pressure plasma (APP) was applied to examine microbial safety and qualities of commercial Sunsik. APP was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air) and dielectric barrier discharge plasma treatment was applied for periods of 0, 5, 10, and 20 minutes. The total aerobic bacterial count in the control was 4.44 log CFU/g. Under plasma treatment for 20 minutes, Sunsik samples inoculated with Bacillus cereus, B. subtilis, and Escherichia coli O157:H7 resulted in a reduction of bacterial counts by approximately 2.20, 2.22, and 2.52 log CFU/g, respectively. The pH of the sample was found to decrease after APP treatment. Although hunter color $L^*$ of Sunsik increased, $a^*$ and $b^*$ value decreased as a result of APP. Increasing the APP time also enhanced the peroxide value. Further, sensory evaluation revealed that APP decreased color, flavor, taste and overall acceptability. The results of this study indicated that APP treatment improved the microbial quality of Sunsik, although further studies should be conducted to reduce the deterioration of sensory quality induced by APP.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.233-238
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• 2004

Foxtail Millet Takju was treated with heat ($65^{\circ}C/30\;min$) (HT) or high hydrostatic pressure ($27^{\circ}C/400\;MPa/10\;min$) (PT), and changes in microbial count, enzyme activity, and quality were determined during 30-day storage at 10 and $25^{\circ}C$. Total viable cellcount remained constant, while lactic acid bacteria and yeast were not detected in HT and PT Takjus. Relative activities of ${\alpha}-amylase$ in PT Takju significantly increased by 169.7% at 3 days storage, then decreased to 137.7 and 68.7% at 10 and $25^{\circ}C$, respectively, at 30 days. Relative activities of glucoamylase in HT Takju showed reversible change, and were 36.5 and 54.3% at $10\;and\;25^{\circ}C$, respectively, at 30 days storage. Activities in PT Takju increased with storage period, 158.2% at 30 days storage at $10^{\circ}C$. Titratable acidity in untreated Takju increased, while those in HT and PT Takjus remained almost constant during 30 days storage. Reducing sugar content in untreated Takju showed no change, while that in HT Takju increased gradually, reaching 2.9% at 30 days, whereas that in PT increased sharply after 3 days, reaching 4.8% at 30 days. Sensory evaluation showed sourness and bitterness were low, and sweetness and overall acceptance were high in PT Takju after 30 days storage at $10^{\circ}C$.

• Korean Journal of Poultry Science
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• v.18 no.2
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• pp.97-119
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• 1991

Effect of Streptococcus faecium(SF) and an antibiotic, Colistin(Col), supplemented to diets singly or in combination, on the performances and changes of intestinal population of microflora of broiler chicks studied. A total of 252, day-old chicks(Arbor Acre) of mixed sex(M：F＝1：1) were alloted into six groups. A diet with no Col and SF was referred as a control diet. The basal diets were added with two levels of SF, 0.04 and 0.08%, singly or in combination with Col 10ppm Another diet was prepared by adding only Col 10 ppm. Numbers of the microorganism in diets added with SF 0.04% and 0.08% were 7$\times$10$^{4}$ and 1.4$\times$10$^{5}$ /g diet respectively The diets consisting of corn and soybean meal as major ingredients were fed for a period of seven weeks . During the feeding trial, fresh excreta were sampled at the end of every week in a sterilized condition to count microbial changes from each dietary group. Microbial changes of large intestine were also measured from nine birds sacrificed at the end of the 4th and 7th weeks each time per dietary group. Excreta from all the groups were also collected quantitatively at the end of 3rd and 6th weeks to measure digestibility of the diets, At the end of 7th week, nine birds from each group were also sacrificed to measure weight changes of gastrointestinal tracts . Average body weight gains of broilers fed the diets added with SF 0.08% (2.37kg) or SF 0. 08%+col 10ppm(2.34kg) were significantly larger than that of the control(2.18kg). The weight gains of the other groups were not statistically different from that of the control Feed/gain ratios of the supplemental groups were better than that of control (P＜0.05) except that of birds fed the diet added only with SF 0.04%. Digestibilities of nutrients such as dry matter, crude protein, crude fat and total carbohydrates were not altered by the consumption of the diets added with SF and/or Col throughout the whole feeding period. As expected, the numbers of Streptococci in the excreta from birds fed diets added with SF increased significantly with a statistical difference between groups with SF 0.04% and SF 0.08% most of the time. However. addition of Colistin to the diets supplemented with SF did not give any effects on the number of the microorganism. Numbers of coliforms in the excreta were apparently reduced by feeding the diets added with SF and/or Col(P＜0.05). There were, however, no additive effects observed between the two feed additives in this regard when supplementing Col to the SF diets. Distributions of intestinal microflora exhibited exactly the same pattern as those of the excreta. Length of small intestine of the birds fed diets added with SF 0.08% with or without Col 10 ppm became significantly longer with a range of about 10% than those of the birds fed diets without SF. However, the empty weight of the small inestine of the former group was lighter than that of control These changes resulted in a significant reduction in weight/unit length of the intestine of the birds fed diets supplemented with Col and SF singly or in combination. In overall conclusion, diet added with SF 0.08% appeared most effective in improving broiler performances. Colistin added at a level of 10ppm was not beneficial at all in itself or in combination with SF in terms of broiler performances or changes of intestinal microflora population. The efficacy of SF and Col could be attributed to the changes of wall thickness of the small intestine.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.23-28
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• 2010

This study was conducted to evaluate the effects of probiotics supplementation on growth performance, nutrient digestibility, fecal concentrations of Lactobacillus and Escherichia coli, emission of noxious gases from the feces, and circulating concentrations of the blood cells in early-finishing pigs. A total of sixty pigs [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] (initial body weight 56.48 ${\pm}$ 1.66 kg) were used for the 28 days feeding trial. Dietary treatments included 1) CON (basal diet), 2) P1 (CON + 0.1% Agariemycetes) and 3) P2 (CON + 0.2% Agariemycetes). There were three dietary treatments with five replicate pens per treatment and four pigs per pen. There was no significant difference in ADG (average dairy gain) among the treatments (P>0.05). The gain/feed ratio was higher in P2 than CON (P<0.05). The P2 showed the highest digestibility of dry matter and energy (P<0.05). No significant difference was observed in the fecal Lactobacillus counts but fecal Escherichia coli population of P2 was lower than that of CON (P<0.05). The ammonia, $H_2S$ and total mercaptan was higher in P1 and P2 than CON (P<0.05). Blood characteristics were not affected by probiotics (P>0.05) supplementation. In conclusion, the results showed that dietary supplementation of probiotics at 0.2% level affected gain/feed ratio, dry matter and energy digestibility; reduced fecal Escherichia coli and emission of fecal noxious gases in finishing pigs.