• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.710-715
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• 1997

Inactivation of lipoxygenase activity in Chinese cabbage was shown after salting and heat treatments. Crude lipoxygenase was obtained from treatment of $(NH_{4})_{2}SO_{4}$. Lipoxygenase activity in Chinese cabbage was about 50% after 20 hrs of salting in 13% (w/v) concentration. After heating at $90^{\circ}C$ for 15 min, residual activity of lipoxygenase was about 50%. Inactivation of lipoxygenase was highly accelerated by increasing temperature and heating time. Decimal reduction time (D-value) were 42, 20 and 14 min at 70, 80 and $90^{\circ}C$, respectively. When cabbage was soaked in 0.05 M $CaCl_{2}$ and heated at $55^{\circ}C$ for 1.5 hr, higher activity of crude lipoxygenase was found compared with the heat treatment without $CaCl_{2}$.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.281-286
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• 2010

The objective of this study was to analyze the microbial populations in the raw ingredients of kimchi and their changes during an automated commercial manufacturing process. High population numbers of total aerobic bacteria, lactic acid bacteria, Leuconostoc sp., and yeast were detected in garlic, ginger, red pepper powder and this result revealed that these ingredients were the major source of microbials in kimchi. Additionally, during the salting process of Chinese cabbage, rapid microbial growth was observed and the consecutive washing process was determined to be ineffective, lowering the microbial count by only one log reduction. Yeast was also detected in various ingredients. These results strongly suggest that, in order to lower the microbial population numbers in kimchi, the side-ingredients and salting process should be subjected to the appropriate sanitization or sterilization processes at the HACCP level. Beside, treatment of salted Chinese cabbage with sodium hypochlorite solutions after the salting step is recommended. To inhibit yeast growth, appropriate chemical treatment and approval of additive uses to control microbials should be considered. These experimental results and suggestions will be used to improve the kimchi manufacturing process in factories.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.73-77
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• 1994

This study was conducted to investigate and make comparison between treatment which was reduced the reducing sugar content from Chinese cabbage using salting and desalting processes prior to Kimchi fermentation , and control for the effect of reducing sugar content on Kimchi fermentation at $25^{\circ}C$. In the early stage of Kimchi fermentation , the amount of reducing sugar (5.7mg/ml) in treatment was much smaller than that (15.1mg/ml) in control. Reducing sugar content of treatment decreased drastically during the first two days and then levelled off . Whereas, that of control dropped significantly up to the first four days of fermentation. pHs of treatment and control decreased significantly during the first two days and then showed gentle slopes. Acidities of treatment and control were increased continuously during the entire range of fermentation . The acidity of control reached to 0.75% in 3 days of fermentation, while that of treatment was shown after 6 days. Hardnesses of treatment and control using a puncture test were almost constant and the hardness value of treatment was higher than that of control during whole fermentation period. The total bacteria and lactic acid bacteria counts increased drastically during the first day of fermentation and the increase of total bacteria counts was mainly caused by that of lactic acid bacteria counts.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.417-423
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• 2011

Salted Cabbage products purchased from different companies at 4 different districts in South Korea were detected in this study. Cabbage and salt are the main materials for kimchi manufacture. The results of general bacteria contaminated in the samples were $1.4{\times}10^5$, $6.4{\times}10^5$, $1.7{\times}10^7$, $3.6{\times}10^7$ CFU/g in cabbage and $2.7{\times}10^3$ CFU/g in salt, respectively. The results of coliforms were detected as $2.4{\times}10^4$ CFU/g, and there was no Escherichia coli in any sample. Staphylococcus aureus was detected in cabbage as $9.9{\times}10^2$, $8.0{\times}10^1$, and $3.0{\times}10^3$ CFU/g, Bacillus cereus was also found in cabbage as $4.1{\times}10^3$ and $1.0{\times}10^1$ CFU/g. The results of Campylobacter jejuni and Vibrio paraheamolyticus were $2.4{\times}10^6$ and $1.0{\times}10^4$ CFU/g in cabbage, respectively. $1.0{\times}10^3$ CFU/g for Yersinia enterocolitica was determined in salt. In case of Listeria monocytogenes, the results were $1.5{\times}10^1$, $1.1{\times}10^2$, and $4.5{\times}10^1$ CFU/g in cabbage. Total batcteria ranged from $1.4{\times}10^1$ to $4.4{\times}10^5$ CFU/g were detected in salting solution, from $1.5{\times}10^4$ to $1.2{\times}10^8$ CFU/g in dehydrated salted-cabbage, from $9.4{\times}10^4{\sim}1.3{\times}10^8$ CFU/g in minced salted-cabbage. The results of E. coli in samples from different companies were different from one to anther. The results of the contamination of S. aureus and B. cereus showed positive in salting solution and dehydrated salted-cabbage at a portion of companies. V. paraheamolyticus was detected in salting solution. The contamination of Y. enterocolitica ranged from $9.5{\times}10^2$ to $1.8{\times}10^3$ CFU/g in salting solution, from $1.7{\times}10^1$ to $2.7{\times}10^2$ CFU/g in dehydrated salted-cabbage, from $1.2{\times}10^2$ to $1.3{\times}10^8$ CFU/g in minced salted-cabbage. The contamination of L. monocytogenes ranged from $8.0{\times}10^2$ to $1.7{\times}10^4$ CFU/g in salting solution, from $2.8{\times}10^2$ to $1.2{\times}10^4$ CFU/g in dehydrated salted-cabbage. During the manufacture processing of Kim chi, microorganisms were detected in cabbages salted in different concentrations of salt solution at 8%, 10%, 12% and 15% for 5-20 hours. As the results, $3.5{\times}10^5-1.7{\times}10^6$, $3.4{\times}10^5-2.5{\times}10^6$, $5.4{\times}10^5-2.3{\times}10^6$, $4.0{\times}10^5-2.3{\times}10^6$ CFU/g were detected for E. coli in samples at different treatment conditions. $1.9{\times}10^4-4.1{\times}10^4$, $4.1{\times}10^3-2.8{\times}10^4$, $1.5{\times}10^3-7.8{\times}10^3$, $2.2{\times}10^4-6.6{\times}10^4$ CFU/g were detected for S. aureus in samples at different treatment conditions. Salmonella typhimurium was detected in salted cabbage with various salt concentration after salting for 5 hrs, the result ranged from $2.5{\times}10^5$ to $3.8{\times}10^6$ CFU/g, and change of microorganism was the smallest in salted cabbage under the concentration of salting solution at 10% for 15 hours. The cabbage salted in 10% salting solution for 15 hours were washed with water for 2 and 3 times, with chlorine for 3 times, and with acetic acid for 3 times. E. coli was detected in the samples washed with water for 2 and 3 times, washed with chlorine for 3 times. The contamination of S. aureus was $3.0{\times}10^5$ CFU/g in the samples washed with water for 2 times, $5.6{\times}10^3$ CFU/g in the samples washed with acetic acid for 3 times, $3.6{\times}10^5$ CFU/g in the samples washed with water for 3 times and same amount in the samples washed with chlorine for 3 times. According to the results, the contamination of S. aureus was $5.6{\times}10^3$ CFU/g lower in samples washed with chlorine and acetic acid than that in samples washed with water. In case of S. typhimurium, it has been detected in samples washed with water and chlorine, $3.0{\times}10^1$ CFU/g as the lowest concentration among all the samples was measured in the samples washed with acetic acid for 3 times.

• Journal of Animal Science and Technology
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• v.54 no.1
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• pp.35-41
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• 2012

The aim of this study was to offer information about appropriate processing method for dry cured-ham with controlled ripening condition. In this study, three different treatments were performed: High salt group (HS), 18 hams were salted with 70 g $kg^{-1}$ salt (w/w) Middle salt group (MS), 18 hams were salted with 50 g $kg^{-1}$ salt Low salt group (LS), 18 hams were salted with 30 g $kg^{-1}$ salt. Also three drying periods were applied (180 days, 270 days and 360 days). The weight loss in HS was higher (5.62%) on curing step and in LS was higher (12.35%) on post-salting step compared to other groups. On fermentation stage, weight loss of HS was higher than that of LS (p<0.05). Weight loss on drying was increased as the drying period passes (p<0.05). Moisture contents were significantly (p<0.05) decreased and fat contents were significantly (p<0.05) increased in all treatment groups as drying period increased. The different drying periods affected fatty acid compositions on all salting levels; saturated fatty acid contents were increased (p<0.05) with more drying, whereas unsaturated fatty acid contents were decreased (p<0.05) as drying period increased.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.13-21
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• 2011

"Manggaedduk" produced specially in Uiryeong province, Gyeongnam, Korea is manufactured by traditional method using rice powder, sweet azuki bean paste, and leaves of Smilax china (called as Manggae-leaf). Moisture content of leaves did not show significant differences bay salt and purified salt treatment. The content was lower as the salt concentration increased. Shear force was higher in leaf salted with purified salt at room temperature than that salted with bay salt. On the other hands, the force was more higher in the leaves salted with bay salt at low temperature ($4^{\circ}C$). The shear force was higher as the concentration of both salts used for salting solution increased. As storage period was extended, shear force of salted leaf was weakened. Whiteness (L) and yellowness (b) of leaves stored at room temperature were higher than those stored at $4^{\circ}C$, although the redness (a) of Hunter value was not significantly different between storage temperatures. Salt concentration influenced lightness and yellowness, color of salted leaves stored at $4^{\circ}C$ resulted in enhanced greenness as compared to the leaves stored at room temperature. Thus, this study investigated the optimal storage conditions, salting conditions and storage temperatures of Smilax china leaves.

• Membrane and Water Treatment
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• v.7 no.2
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• pp.101-113
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• 2016

In this study, to improve the water flux of porous hydrophobic membranes, various water-soluble polymers including neutral, cationic and anionic polymers were adsorbed using 'salting-out' method. The adsorbed hydrophobic membrane surfaces were characterized mainly via the measurements of contact angles and scanning electron microscopy (SEM) images. To enhance the durability of the modified membranes, the water-soluble polymers such poly(vinyl alcohol) (PVA) were crosslinked with glutaraldehyde (GA) and found to be resistant for more than 2 months in vigorously stirred water. The water flux was much more increased when the ionic polymers used as the coating materials rather than the neutral polymer and in this case, about 70% of $0.31L/m^2{\cdot}h$ (LMH) to 0.50 LMH was increased when 300 mg/L of polyacrylamide (PAAm) was used as the coating agents. Among the cationic coating polymers such as poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA), poly(acrylic acid-comaleic acid) (PAM) and poly(acrylic acid) (PAA), PSSA_MA was found to be the best in terms of contact angle and water flux. In the case of PSSA_MA, the water flux was enhanced about 80%. The low concentration of the coating solution was better to hydrophilize while the high concentration inclined to block the pores on the membrane surfaces. The best coating condition was found: (1) coating concentration 150 to 300 mg/L, (2) ionic strength 0.15, (3) coating time 20 min.

• Food Science and Preservation
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• v.14 no.1
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• pp.24-29
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• 2007

Quality changes in winter Chinese cabbages were evaluated during low temperature storage. Flesh and salt-treated Chinese cabbages were put into (a) polyethylene (PE) film sacks (size: $40cm{\times}60cm$, thickness: 0.03 mm, with four perforations each 8 mm in diameter), (b) plastic containers or (c) polypropylene (PP) nets and stored at $0^{\circ}C$. Also, Cabbages were also wrapped in newspapers and stored underground where the average temperature was $2.7^{\circ}C$. The weight loss rates of Chinese cabbages stored in PP nets and plastic containers were greater than those of cabbages stored with PE or wrapped in newspaper. Chinese cabbages wrapped in newspaper and stored underground needed much greater trimming compared to cabbages stored in other ways. The firmness and the soluble solid contents of Chinese cabbages were not affected by the various storage treatments. A better appearance was retained when Chinese cabbages were stored in PE film sacks. Chinese cabbages in PE film sacks stored at $0^{\circ}C$ showed delayed weight loss, less trimming loss, and less change in appearance. The quality changes in salted Chinese cabbages (desalting losses, pH changes, osmolarities, and crude fiber content) were not significantly different after the various treatments. No storage treatment was effective in maintaining a high quality of salted winter Chinese cabbage.

• Culinary science and hospitality research
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• v.23 no.8
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• pp.98-105
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• 2017

The purpose of this study was to investigate changes in physicochemical properties of apples pre-treated differently with salt and sugar for apple Jangachi. When salt was used, moisture content was decreased by 28.41% to 57.67% at 24 hours and maintained an average 56.92% after 24 hours. However, when sugar was used, moisture content decreased steadily to 41.14% (60h). The pH of the apple pre-treated with salt decreased from pH 4.42 to pH 3.63 at 12 hours. However, in the case of apples pre-treated with sugar, pH decreased from pH 4.52 to pH 4.19 after 48 hours, but was not statistically significant. Conversely, total acidity of apple pre-treated with salt increased from 11.46% to 0.35% during 72 hours. But total acidity of apple pre-treated with sugar decreased to 0.11% at 24 hours and maintained. Sugar content of apple pre-treated with salt increased to 33.1% at 12 hours and maintained. Conversely, in case of sugar pre-treatment, sugar content of apple pre-treated with sugar increased steadily to 45.12% at 72 hours. Salinity of apple pre-treated with salt increased sharply to 15.74% during 24 hours. Lightness ($L^*$) of apple pre-treated sugar was not different from the control group. But apple pre-treated salt decreased slightly. Yellowness ($b^*$) was higher than the control group regardless of pre-treatment group. Sensory evaluation revealed that sugar pre-treatment apples were highly evaluated for flavor, taste, chewiness and overall acceptance.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.270-277
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• 2003

In order to enhance the firmness and shelf-life of kimchi, as well as to increase the content of well-absorbed digestible calcium, the effect of calcium lactate (CaL) treatment of salted Chinese cabbage on pH, tit ratable acidity, total microbes, lactic acid bacteria, alcohol insoluble substance (AIS) content, firmness, mineral content and tissue structure were investigated. Treatment with the Cal solution increased pH and decreased titratable acidity, which was more pronounced at higher concentrations. The edible period evaluated by pH was 7～8 days for non-treated kimchi, 10 days for 1 % treated kimchi, 15 days for 2% treated kimchi and 20 days for 3% treated kimchi. Total microbes were reduced, but lactic acid bacteria counts were higher in the treated group. CaL treated kimchi showed higher AIS content and firmer texture, which was more conspicuous in the 2 and 3% CaL treated groups. Calcium content in kimchi fermented for 15 days was 40.75～41.53 mg%, which is 42～45% higher than that in the control group. The sodium content was 23～54% less in the treated groups. The epidermis and vascular bundle tissue of kimchi fermented for 15 day was damaged more severely in the control group than in the treated group. CaL treated kimchi has a crispier taste and the development of sour taste was delayed. Therefore, addition of CaL can produces a kimchi with high calcium as well as superior texture and shelf-life, when adjusting the concentration according to the fermentation periods.