• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.837-841
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• 2004

Changes in total aerobic bacteria (TAB), lactic acid bacteria (LAB), rod- and coccal-shaped lactic acid bacteria (R- and C-LAB), pH, and total acidity were investigated during fermentation of radish with new fermentation base at $20^{\circ}C$ for up to 16 days. New fermentation base was prepared by pre-fermenting a mixture of rice bran and rice water (1 : 0.1, w/v) at $20^{\circ}C$ for 7 days. Initially, radish showed 5.41, 4.23, 4.57, and 3.1 log CFU/g, and base showed 6.68, 6.60, 5.95, and 5.6 log CFU/mL for TAB, LAB, R-LAB, and C-LAB, respectively. Initial pH and total acidity of radish were $6.6^{\circ}C$ and 0.09%, and those of base were 5.76 and 0.36%, respectively, Counts of LAB (4.23 to 8.33 Bog Cpu/g, 6.6 to 9.7 log CFU/mL), R-LAB (4.57 to 7.15 log CFU/g, 5.95 to 8.5 log CFU/mL), and C-LAB (3.1 to 7.5 log CFU/g, 5.6 to 8.6 log CFU/mL) of radish and base respectively increased during initial fermentation period, then remained constant during late fermentation period, and far 4 days after fermentation, pH values (6.6 to 4.19, 5.76 to 4.57) drastically decreased and thereafter slowly decreased. Total acidities of radish and base (0.09 to 0.63%, 0.36 to 0.63%, respectively) drastically increased far 7 days after fermentation and increased slightly thereafter.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.476-481
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• 1997

For the effect of water-soluble degraded chitosan on the shelf-life of tofu, sterilized distilled water, 0.5% degraded chitosan, 0.5% fumaric acid and 0.5% lactic acid used as an tofu-immersion solutions were investigated by microbial counts, pH, and turbidity during the periods of storage at $4^{\circ}C$. After 2 weeks storage, total aerobic microbial counts in tap water and sterilized distilled water used as an immersion solution were $3.8\;{\times}\;10^8$ and $1.8\;{\times}\;10^8\;CFU/mL$, respectively. In 0.5% fumaric acid and 0.5% lactic acid immersion solutions, the microbial counts were around $10^7\;CFU/mL$ after 2 weeks while the microbial population in 0.5% water-soluble degraded chitosan were, however, $1.6\;{\times}\;10^5\;CFU/mL$ after 2 weeks and $1.7{\times}10^7\;CFU/mL$ after 3 weeks. The lag phase of initial contaminated microbes in 0.5% degraded chitosan solution was longer than those of other treatments. The addition of 0.5% fumaric acid and 0.5% lactic acid decreased the initial pH to pH 5.0, while those of tap water, sterilized distilled water and 0.5% degraded chitosan stabilized the immersion solution at around pH 7.2. All initial pH values were decreased during storage and then slowly increased as storage time was increased. The turbidities in all treatments were increased during storage, but the addition of 0.5% degraded chitosan showed the lowest change, compared to other treatments, showing that the water-soluble degraded chitosan has a good antimicrobial effect and has a potential use to extend the shelf-life of tofu product.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.729-733
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• 2005

This study was conducted to sanitize fried-frozen cheese ball by gamma irradiation. Total aerobic bacteria and yeasts and molds counts were 4.4 and 2.8 log CFU/g in non-irradiated sample, respectively. Microorganisms were decreased with increase of irradiation dose $(D_{10}=1.25\;kGy)$, and were not detected in samples irradiated at 3 kGy or more $(<10^2\;CFU/g)$. $D_{10}$ value for Escherichia coli (KCTC 1682) was 0.25 kGy. TBA (2-thiobarbituric acid) values were increased as irradiation dose was increased, but there was no significant difference between non-irradiated and irradiated samples at 3 kGy or less (p<0.05). The results of sensory evaluation showed that there was no significant difference between non-irradiated and irradiated samples at 3 kGy or less, the sensory scores were decreased with irradiation at 5 kGy or more (p<0.05). These results indicated that gamma irradiation at 3 kGy was considered to be an effective treatment to ensure the microbiological safety of fried-frozen cheese balls without any sensorial change, even though further studies should be investigated to reduce detrimental effects induced by irradiation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.335-342
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• 2011

The purpose of this study was to investigate the effects of mugwort powder on the quality characteristics and antioxidant activity of Maejakgwa. Maejakgwa were prepared with mugwort powder at levels 0%, 1%, 3% and 5% ($60{\pm}1^{\circ}C$, 14 days). The lightness, redness, and yellowness values of Maejakgwa significantly reduced depending on mugwort powder. The hardness of Maejakgwa was decreased with the increase of storage period and increased with the increase of mugwort powder. In the sensory evaluations, the Maejakgwa prepared with 3% added mugwort powder received higher acceptance scores for the properties of color, taste, hardness, crispiness, adhesiveness and overall acceptability. As the mugwort powder content increased, acid value and peroxide value were decreased. With the increase of storage period, acid value and peroxide value of all sample increased but growth rate of these values decreased with the addition of the mugwort powder. DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity was improved significantly via the addition of mugwort powder and decreased as storage period increased. During storage period, Maejakgwa with mugwort powder showed a stronger antimicrobial effect in yeasts and molds than in total aerobic bacteria. Coliform bacteria were not detected in all samples. Also the antimicrobial activity was increased with the addition of the mugwort powder and decreased as storage period increased. The results show that addition of the mugwort powder to foods with fat such as Maejakgwa would be a useful way to enhance the antioxidant quality, sensory characteristics and shelf life.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.5
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• pp.352-363
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• 2002

The purpose of this study was to analyze health-related habits, weight control experience and body composition of 344 female students visiting nutrition counselling office. Dietary habits of the subjects were assessed by means of interview with questionnaire and nutrient intakes were evaluated by the simple dietary assessment method. Weight and height were measured to get body mass index(BMI) and waist-hip ratio and their body composition were measured by Inbody 3.0. The obtained results were as follows: 1) Among students, 14.5% were exercising on a regularly basis, of which the exercises were walking and gymnastic exercise(22.1%), jogging(14.1%), and rope-skipping(4.7%), 48.4% of students were little drinking and 30.5% were once a week and smokers were 4.1%. 2) 28.3% of students were little having breakfast and 15.1% were once or twice a week. Two third of total students were not having breakfast regularly. Also only 59.6% of students were having dinner everyday, which means many of them were even skipping dinner. The reasons why they were not having breakfast were because they don't have enough time to eat(66.0%) and for a diet(2.8%) and the reasons for skipping dinner were because they were not hungry(23.0%), for the weight loss(18.2%). It was shown that they would skip dinner rather than breakfast for a weight control. 51.6% of students were taking snack 1~2 times a day and 5.3% were having little snack. 55.4% of students were dining out once a day and 15.4% more am 2 times a day. 3) 46.7% of students were already experiencing weight control before visiting the counselling office. 78.5% of students tried on one kind of weight control method, 11.4% on two kinds, and 10.1 % on more than three kinds. The method they tried for a weight control most was the one food diet using egg, fruits and beans, which is the most popular among them, and the next were an aerobic exercise(23.6%). a diet tried by a famous entertainer (15.5%), and the fasting(14.5%). 4) The average BMI was 21.2 and the body fat rate was 28.1%. As a result of grouping BMI, 12.8% were underweight 67.6% normal weight 11.6% overweight and 8% obesity. Less than standard for the body fat rate were 0.6%, 50.6% standard, 48.5% more than standard. 49.2% of students as normal weight on a BMI were assessed the so-called "skinny obesity. 50% of consulted students situated fat intra-abdominally at the umbilical level(WHR>0.8). 5) The energy intake was 76.6$\pm$17.8% of RDA and constituent ratio of carbohydrate, fat and protein were 64.2$\pm$5.2%, 21.6$\pm$3.7% and 14.3$\pm$2.3%, respectively, which is little over of 20% of recommended ratio of fat. Protein and niacin intake were more than 90% of RDA and riboflavin and vit. C were taken more than 100% of RDA. But Fe intake was 69.4$\pm$19.3%, Ca 76.6$\pm$23.6%, which were the least constituents. There was not remarkable significance between energy intake and nutrient density based on the groups of underweight, normal weight, overweight and obesity of BMI. 6) It was shown that body fat rate had remarkably significant correlation(p<0.000) with BMI(r=0.760) and WHR(r=0.817) respectively, but body fat rate was more correlated with WHR than with BMI. There was not much significant difference between body fat rate and WHR whether they exercised or not. However. BMI was significantly higher in the exercise group because one who showed higher BMI started to exercise since they looked fat in appearance and perceived as they were fat. fat.

• Food Science and Preservation
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• v.21 no.2
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• pp.163-169
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• 2014

The effect of the combined argon (Ar) gas packaging treatment on the browning of fresh-cut potatoes was studied. Fresh-cut potatoes were prepared for the following six groups: dipping distilled water for 1 minute and air packaging (Cont); dipping in distilled water for 1 minute and argon gas packaging (AR); dipping in 1% ascorbic acid for 1 minute and air packaging (AA); dipping in 1% ascorbic acid for 1 minute and argon gas packaging (AAR); blanching at $35^{\circ}C$ for 30 minutes and air packaging (BL); and blanching at $35^{\circ}C$ for 30 minutes and argon gas packaging (BAR). The potatoes were washed, peeled, and sliced ($1.5{\times}1.5{\times}1.5$ cm) before treatment. The samples were packed with a 0.04-mm-thick OPP film and were stored at $5^{\circ}C$ for 9 days. During the storage, the $O_2$ concentration decreased in Cont but increased in the AR, AA, AAR, BL, and BAR groups. The $CO_2$ concentration increased during storage. The AR, AAR, and BAR groups showed high $L^*$ and low $a^*$, $b^*$ values (browning index). The growth of the total aerobic bacteria was also inhibited in the AR group. During storage, the PPO activity gradually increased, and the AR group showed lower PPO activity. The AA and AAR groups showed high DPPH radical scavenging activity. It was demonstrated that the argon gas packaging is effective in the quality maintenance of fresh-cut potatoes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1906-1912
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• 2014

To evaluate the effect of freezing temperature on quality of blueberries, blueberry fruit was frozen at -20, -45, and $-70^{\circ}C$ immediately after harvest. After 24 hr of freezing, frozen blueberries were stored at $-20^{\circ}C$ for 2 months. Blueberries were thawed at $4^{\circ}C$ or $25^{\circ}C$ and subjected to subsequent analyses of drip ratio, fruit hardness, pH of juice, color, and sugar content. Frozen berries at all three temperatures did not show any significant difference in pH or sugar content compared with fresh berries. The drip ratio of berries decreased as the freezing temperature decreased. Thawing conditions significantly affected the drip ratio of berries frozen at $-20^{\circ}C$. Hardness of berries was significantly reduced after freeze-thawing. Freezing and thawing reduced total aerobic bacteria and yeast/mold numbers by more than 2 log regardless of freezing or thawing temperature ($4^{\circ}C$ or $25^{\circ}C$). Cross-section of blueberries did not show different shapes by freezing temperature. Further studies such as sensory evaluation are needed to determine the optimum freezing temperature regarding quality and cost.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1225-1233
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• 2017

The aim of this study was to evaluate the microbial inhibitory activity and physicochemical quality of fresh carrot juice prepared with different environmentally-friendly washing methods during low temperature storage. Individual and combined treatments with sodium bicarbonate (baking soda, $NaHCO_3$) and citric acid were applied to carrots for 10 min. Tap water and 50 ppm of sodium hypochlorite (NaOCl) were used as the control. Combined treatment of 1% $NaHCO_3$ and 1% citric acid significantly reduced total aerobic counts and coliforms. In addition, combined treatment of 1% $NaHCO_3$ and 1% citric acid inhibited microbial growth for 7 days at $4^{\circ}C$ and $10^{\circ}C$ in a shelf-life study. There were no significant differences among the sanitizers in terms of $^{\circ}Brix$, acidity, pH, and color. Changes in physicochemical quality were not significantly different by sanitizer but were affected by storage temperature. These results indicate that washing with combined treatment of 1% $NaHCO_3$ and 1% citric acid is an effective method to inhibit the microbial population and maintain physicochemical quality. Therefore, combined treatment of 1% $NaHCO_3$ and 1% citric acid can be effectively used to sanitize and prepare carrot juice without affecting other properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.379-389
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• 2008

This study was conducted to assess the microbiological quality of raw and cooked foods served in the elementary school food service. Raw and cooked food samples were collected from 11 selected elementary schools in both June to July and September to October of 2005. Petrifilm plates were used to determine (in duplicate) total aerobic colony counts (PAC), Enterobacteriaceae (PE), coliform counts (PCC), and E. coli counts (PEC). Heavy contamination of Enterobacteriaceae (from 0.08 to 7.40 log CFU/g) and total coliform (0.50 to 6.52 log CFU/g) were observed in raw materials and cooked foods. Escherichia coli (E. coli) were detected in the sample of currant tomato (3.70 log CFU/g), sesame leaf (3.59 log CFU/g), dropwort (0.20 log CFU/g), crown daisy (3.15 log CFU/g), parsley (3.00 log CFU/g), peeled green onion (1.74 log CFU/g), frozen pork (0.65 log CFU/g), frozen beef (0.20 or 1.50 log CFU/g), chicken (1.78 log CFU/g), and young radish leaf seasoned with soybean paste (1.24 log CFU/g). Multiplex PCR system was used to determine the food-borne pathogens: Salmonella spp., Bacillus cereus (B. cereus), E. coli O157:H7, Staphylococcus aureus, Listeria monocytogenes (L. monocytogenes), Vibrio parahaemolyticus, Campylobacter jejuni (C. jejuni), Shigella spp., B. cereus was detected in 19 samples of raw materials and 8 samples of cooked foods. With regard to quantitative analysis, B. cereus counts exceeded 5.46, 3.48 and 1.79 log CFU/g in sesame leaf, peeled green onion and seasoned mungbean jelly, respectively. E. coli O157:H7 was detected on 2 samples of frozen beefs, and its biochemical characteristics of one beef sample was confirmed with API 20E kit (93.7%). L. monocytogenes was detected in fried rice paper dumpling, but the presumptive colonies were not detected onto the conventional plate. C. jejuni was detected in peeled & washed onion.

• Food Science and Preservation
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• v.15 no.3
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• pp.367-376
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• 2008

This study was conducted to investigate 1he quality characteristics of 1he soybean anchovy sauces added with medicinal herbs, Saururu chinensis Baill. and Houttuynia cordata Thunb. and fermented for 4 months. The total nitrogen content of 1he soybean anchovy sauce increased with the fermentation time showing the highest values in the sauce with Houttuynia cordata Thunb.. The contents of total sugar and reduced sugar were high in the order of the sauces with Houttuynia cordata Thunb.(sauce T), with Saururu chinensis Baill.(sauce B), and control. The content of salt decreased much more in the sauces with medicinal herbs. After 4 months of fermentation, pH was lowered from 5.86 to 5.27 in control, to 5.38 and 5.54 in sauce B and sauce T, respectively. Generally the total aerobic bacterial count increased until 3 months of fermentation and then decreased, and the addition of medicinal hems reduced the count especially showing apparent reduction in the sauce T. During the fermentation, total protease activity generally increased with the highest value in the sauce T. In the changes of nucleotides and their related compounds, the contents of AMP, ADP, and ATP were increased and hypoxanthine decreased during the fermentation, and IMP produced after 3 months. The soybean anchovy sauce B had 1he highest IMP and the lowest hypoxanthine after 4 months. The content of total amino acids increased showing 177.1 mg% and 134.7 mg% in the sauce B and sauce T respectively compared with 171.2 mg% of control. The contents of glutamic acid and aspartic acid were 29.2 mg% in sauce B and 34.3 mg% in sauce T, which were higher compared with 25.9 mg% of control. The fermented soybean anchovy sauce had 1he functionality of ACE inhibition with 70.5% (control), 72.5% (sauce B) and 81.6% (sauce T). In the results of sensory evaluation, the sance T scored the highest and the sauce B was preferred to control.