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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Journal of Food Science and Technology
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Journal DOI :
Korean Society of Food Science and Technology
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Volume & Issues
Volume 45, Issue 6 - Dec 2013
Volume 45, Issue 5 - Oct 2013
Volume 45, Issue 4 - Aug 2013
Volume 45, Issue 3 - Jun 2013
Volume 45, Issue 2 - Apr 2013
Volume 45, Issue 1 - Feb 2013
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Antioxidant Activities in Freeze-dried and Hot Air-dried Schizandra Fruit (Schizandra chinensis Baillon) at Different Microwave-asssisted Extraction Conditions
Park, Eun-Joo ; Ahn, Jae-Jun ; Kim, Jeong-Sook ; Kwon, Joong-Ho ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 667~674
DOI : 10.9721/KJFST.2013.45.6.667
This study was aimed to investigate the effect of microwave-assisted extraction on Schizandra fruit extract dried by two different treatments: freeze-drying and hot air-drying. Two extraction parameters were measured in particular: total polyphenol content and antioxidant activity. Both values were found to increase as the microwave power increased, for both drying processes. However, the extract from the freeze-dried sample exhibited higher antioxidant activity than that from the hot air-dried samples. Additionally, the total polyphenol content and antioxidant activity of the extract from the freeze-dried samples increased with the extraction time, whereas they decreased with the extraction time in the case of the hot air-dried sample. Solvent concentration was also found to have a significant effect on total polyphenol content and antioxidant activity; the highest values for both properties were achieved at 50 and 70% ethanol concentrations, respectively. In summary, a higher total polyphenol content and antioxidant activity were observed for Schizandra fruit extracted by freeze-drying than that by hot air-drying.
Chemical Characteristics and Flavors of Bamboo-shoot Vinegar
Jang, Hyejin ; Lee, Eunsil ; Shim, You-Shin ; Seo, Dongwon ; Hwang, Jinbong ; Lee, Songjin ; Ha, Jaeho ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 675~681
DOI : 10.9721/KJFST.2013.45.6.675
We assessed the quality of a bamboo shoot vinegar produced in Damyang-gun in terms of parameters that included acidity, mineral contents, amino acids, and flavonol aglycones. The flavor compounds of the bamboo shoot vinegar were also analyzed using the stir bar sorptive extraction (SBSE) method. The acidity of the bamboo shoot vinegar was 4.49%, which was the lowest value among the commercial vinegars studied. The bamboo shoot vinegar had a lower concentration of Na (8.36 mg/100 g) than the other commercial vinegars. There was a relatively large amount of tyrosine and lysine in the bamboo shoot vinegar. The concentration of quercetin, a flavonol aglycone, was 3.29 mg/100 g. The results of the flavor analysis showed that hexanal, 2-furancarboxaldehyde, and benzaldehyde were high in the bamboo shoot vinegar. Oleamide, a compound that is known to induce sleep, was first found in bamboo shoot vinegar using the SBSE method.
Difference of Starch Characteristics of Sweetpotato (Ipomoea batatas (L.) Lam) by Cultivated Regions
Han, Seon-Kyeong ; Song, Yeon-Sang ; Lee, Hyeong-Un ; Ahn, Seung-Hyun ; Yang, Jung-Wook ; Lee, Joon-Seol ; Chung, Mi-Nam ; Suh, Sae-Jung ; Park, Keun-Hyung ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 682~692
DOI : 10.9721/KJFST.2013.45.6.682
We investigated out the effect of cultivation region on the physicochemical characteristics of starch in six sweetpotato cultivars. The following sweetpotato cultivars were analyzed: Daeyumi, Shingeonmi, Jinhongmi, Shinyulmi, Yulmi, and Yeonhwangmi. Samples were cultivated in Muan, Iksan, Nonsan, Boryeong and Hamyang. The soil texture was found to be sandy loam in Muan, Iksan, and Boryeong, sandy clay loam in Nonsan, and loam in Hamyang. The starch content of the sweetpotato was higher in Muan than in Hamyang. The amylose content was 22.3-30.9%, and the highest amylose content was found in samples from Iksan. Rapid viscosity analysis showed that the samples from Hamyang had the lowest values of pasting temperature, while samples of the Daeyumi cultivar had the highest values. Thermal analysis with a differential scanning calorimeter showed that the Muan samples had the highest values of onset temperature, maximum peak temperature, and completion temperature, and the samples from Hamyang had the lowest values. There was no difference between the cultivation regions or the cultivar in the X-ray pattern of the starch or its appearance in scanning electron micrographs. Therefore, the results of this study confirm that cultivation region and cultivar play an important role in determining the quality of sweetpotato and the physicochemical characteristics of sweetpotato starch.
Development of a Method for Analyzing the Nicotine Content in Synthetic Flavoring Substances as Unauthorized E-cigarette Liquid by Using HPLC
Kim, Jae-Young ; Lee, Sang-Mok ; Chang, Moon-Ik ; Cho, Yoon-Jae ; Lee, Han-Jin ; Chae, Young-Sik ; Rhee, Gyu-Sik ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 693~699
DOI : 10.9721/KJFST.2013.45.6.693
A simple, sensitive, and specific method for quantifying the nicotine content of synthetic favoring substances (SFS) was developed using high performance liquid chromatography (HPLC) with a photo-diode array detector (PDA). Nicotine was extracted from SFS samples by using an acid-base liquid-liquid extraction method with dichloromethane and distilled water. The nicotine content was quantified by HPLC/PDA (261.9 nm) with a
column under a gradient of 10% acetonitrile with 20 mM ammonium formate (ammonia solution adjusted to pH 8.7) to 100% acetonitrile. The calibration curve, analyzed from concentration standards between 0.1 to 2 mg/L, presented linearity with a correlation coefficient (
)>0.9999. The limit of quantitation (LOQ) of nicotine in SFS was 0.4 mg/kg, and the average recoveries ranged from 76.4% to 96.3%. The repeatability of measurements, expressed as the coefficient of variation (CV%), ranged from 1.74 to 5.12%. This newly developed method for nicotine quantification in SFS can be considered an analytical method with an acceptable level of sensitivity and repeatability.
Physicochemical Changes in Olive Flounder (Paralichthys olivaceus) Muscle by Iced Water Pre-treatment
Shin, Seung-Ho ; Sung, Ki-Hyub ; Chung, Chang-Ho ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 700~707
DOI : 10.9721/KJFST.2013.45.6.700
The purpose of this study was to monitor physicochemical changes of olive flounder (Paralichthys olivaceus) muscle by iced water pre-treatment. Moisture content, crude fat content, nucleotide content, texture (hardness and toughness), and rigor mortis were assessed. The sensory evaluation was performed with a nine-point hedonic test. K-values, a parameter of fish flesh freshness, were also calculated from the content of nucleotides and their corresponding decomposition products. Pre-treatment of flounder flesh with iced water was found to be fresher compared to the control, as determined by a difference in the K-values. Iced water pre-treatment hastened postmortem stiffness, as judged from the rigor index, and increased inosine monophosphate (IMP), which is known to be a savory taste compound, more quickly as adenosine triphosphate (ATP) degradation proceeded.
Contents of Phenolic Compounds and trans-Resveratrol in Different Parts of Korean New Grape Cultivars
Chang, Eun Ha ; Jeong, Sung Min ; Park, Kyo Sun ; Lim, Byung Sun ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 708~713
DOI : 10.9721/KJFST.2013.45.6.708
The ethanol solvent extracts obtained from the pulp, skin, seeds, leaves, fruit stems, and pruning stems of four Korean new grape varieties ("Dunoori", "Narsha", "Cheongsoo", and "Heukbosek"), as well as "Campbell Early", and "Muscat Bailey A (MBA)" were evaluated for their total phenolic and anthocyanin contents. The concentrations of four phenols of biological interest, catechin, epicatechin, quercetin, and resveratrol in the different parts were quantified by high-performance liquid chromatography-ultraviolet analyses. The skin of "Narsha" and "Heukbosek", the leaves of "Narsha", the fruit stems of "MBA", and the pruning stems of "Campbell Early" and "Heukbosek" had the highest resveratrol content. In particular, the resveratrol in the fruit stems of "MBA" had the highest concentration as compared to the other varieties in the different parts. The seeds of "MBA", and the fruit stems of "MBA" and "Heukbosek" had the highest catechin content. Epicatechin was detected in the seeds, fruit stems, and pruning stems. Quercetin was detected only in the leaves. In summary, the catechin and epicatechin contents were significantly higher than the quercetin and resveratrol contents. The concentrations of the physiologically active components present in the grapes were high in the non-edible parts than in the edible parts; therefore, they could be useful in industrial applications.
Brewing and Fermenting Characteristics of Makgeolli Produced from High-yielding Rice Varieties
Lee, Dae Hyoung ; Lee, Yong Sun ; Cho, Chang Hui ; Seo, Jae Soon ; Park, In Tae ; Kim, Heui Dong ; Lim, Jae Wook ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 714~720
DOI : 10.9721/KJFST.2013.45.6.714
We investigated the brewing and fermenting characteristics of makgeolli produced from high-yielding rice varieties. We used the high-yielding indica rice varieties, Anda and Dasan 1, and the japonica varieties, Deuraechan and Boramchan. Our results showed that the rice protein level was the highest in makgeolli produced from Anda (
), while the amylose level was the lowest in makgeolli produced from the mid- to late-maturing japonica varieties (Deuraechan,
). Samples of makgeolli produced from Anda, Deuraechan, and Boramchan by using the Ipguk (Koji) method had an alcohol content of 16.6-17.4% on completion of fermentation. By contrast, makgeolli produced from Dasan 1 had an alcohol content of 14.3%; further, the makgeolli differed significantly in the sensory test and was scored as excellent regarding comprehensive preference. For makgeolli produced by using the uncooked rice fermentation method, samples produced from the indica varieties, Anda and Dasan 1, had lower alcohol contents (17.2% and 17.0%, respectively) and higher total acidity levels (0.33% and 0.31%, respectively) than did samples produced from the japonica varieties, Deuraechan and Boramchan (0.28% for both). In the sensory test, samples produced from Anda and Dasan 1 performed significantly better regarding scent, swallowing, and comprehensive preference.
Quality Characteristics and Antioxidant Activity of Yogurt Added with Whole Barley Floura
Lee, Mi-Ja ; Kim, Kyung-Soon ; Kim, Yang-Kil ; Park, Jong-Chul ; Kim, Hyung-Soon ; Choi, Jae-Seong ; Kim, Kee-Jong ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 721~726
DOI : 10.9721/KJFST.2013.45.6.721
In this study, a yogurt containing skim milk powder and whole barley flour was fermented with lactic acid bacteria, and its quality and properties were estimated. The yogurts with 1% and 3% barley flour had lower pH values, higher titratable acidity, and higher Brix values than the control. In addition, the viable cell counts were lower and viscosity was higher. The value of L was low, and the values of a and b were high. The yogurt with 3% barley flour had more lactic acid than the control and showed a substantial increase in the amount of acetic acid.
-Glucan content and antioxidant activity increased with the amount of barley flour added. In sensory evaluation, there was a similar preference for the yogurt with 3% barley flour and the control, and as the barley flour content increased, the preference decreased. Moreover, the preference for the yogurt was higher among old people.
Quality Characteristics and Biogenic Amine Production of Makgeolli Brewed with Commercial Nuruks
Jeong, Seok-Tae ; Kwak, Hee-Jung ; Kim, Soon-Mi ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 727~734
DOI : 10.9721/KJFST.2013.45.6.727
Makgeolli mashes that were brewed using five different commercial nuruks (fermentation starters) were investigated for changes in physicochemistry, microbial diversity, and biogenic amine (BA) production. Mash A brewed with the nuruk (Gaeryang-nuruk) had the highest level of alcohol concentration and the greatest number of yeast cells, whereas mash E had the greatest number of bacterial cells. Only three biogenic amines were detected in the makgeolli mashes: tyramine, putrescine, and cadaverine. Using a PCR-DGGE technique, we observed that mash E had the highest BA production, and had the greatest number of bands on the denaturing gradient gels. We also observed that the numbers of bacterial cells correlated significantly with the putrescine and the total BA content, and that the BA content correlated significantly with the color values (L, a, b). This study shows that the quality of a makgeolli can depend on the type of nuruk. Therefore, we suggest that the quality management of makgeolli should start with the stage of nuruk manufacture.
Microbial Decontamination of Vegetables and Spices Using Cold Plasma Treatments
Kim, Jung Eun ; Kim, In-Hah ; Min, Sea C. ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 735~741
DOI : 10.9721/KJFST.2013.45.6.735
Effects of cold plasma treatment (CPT) against Salmonella Typhimurium inoculated on cabbage and lettuce, naturally occurring bacteria in black pepper powder and red pepper powder, and Bacillus cereus inoculated onto red pepper powder were investigated. The numbers of S. Typhimurium on cabbage and lettuce were reduced by
(900W, 5 min) and
(900W, 10 min), respectively. The numbers of naturally occurring aerobic bacteria in both black pepper powder and red pepper powder were reduced by
log CFU/g, respectively. The numbers of B. cereus vegetative cells on red pepper powder were reduced by
log CFU/g, but the numbers of spores remained unchanged. The inhibition of S. Typhimurium on cabbage was adequately described by Fermi's model and the Weibull model. The predicted optimum treatment power and time for S. Typhimurium inoculated onto cabbage were 746 W and 6.8 min, respectively. Our results indicate that CPT represents a useful method for microbial decontamination of vegetables and spices.
Effect of Different Steaming and Drying Temperature Conditions on Physicochemical Characteristics of Pumpkin Powder
Shin, Dong-Sun ; Yoo, Seon-Mi ; Park, Bo-Ram ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 742~746
DOI : 10.9721/KJFST.2013.45.6.742
This study was conducted to investigate the effect of different steaming and drying temperature conditions on the physicochemical characteristics of pumpkin powder. All the samples were steamed for 30 or 60 s and then were dried using hot air at 40, 50, 60, and
. The moisture content decreased with an increase in the hot-air drying temperature, while the soluble solid content and yield increased. The color values, L, a, and b of the pumpkin powder decreased with increasing hot-air drying temperature. The pumpkin powder, which was steamed for 60 s had the highest water absorption and water solubility indexes. The carotenoid content of pumpkin powder was mostly destroyed with the increase in the steaming and drying temperatures. The total sugar and reducing sugar contents increased with increasing steaming and drying temperatures. Thus, the steaming and dehydration temperature conditions influenced the physicochemical characteristics of the pumpkin powder.
Physicochemical Properties of Sweet Potato Starch Reclaimed from Sweet Potato Processing Sludge
Kim, Hyun-Seok ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 747~753
DOI : 10.9721/KJFST.2013.45.6.747
The physicochemical properties of sweet potato (SP) starches reclaimed from an SP-processing sludge without freezing (RC/NF) and with freezing (RC/FR) were investigated. Lab-isolated (LI) SP starch, as a control, were prepared from raw SP. RC/NF and RC/FR SP starches were recovered from SP-processing sludges by the repeated sieving and washing procedure. The total starch contents and amylopectin branch-chain distributions did not differ for three SP starches. Relative to LI and RC/NF SP starches (possessing similar physicochemical characteristics), the apparent amylose and phosphorus contents, swelling factor, and pasting viscosity were reduced for RC/FR SP starch. However, the freezing treatment altered X-ray diffraction pattern (at
) of RC/FR SP starch, which likely increased its gelatinization peak and completion temperatures. Its amorphous region in total diffractogram was reduced, resulting in the enhanced relative crystallinity. Overall results suggested SP starches recovered from an SP-processing sludge would have the potential to replace commercial SP starch products.
Relative Sweetness and Sweetness Quality of Low Calorie Sweeteners in Milk and Coffee Model System
Choi, Ji-Hye ; Kim, Kwang-Pyo ; Chung, Seo-Jin ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 754~762
DOI : 10.9721/KJFST.2013.45.6.754
This study investigated the relative sweetness of various sweeteners (tagatose, xylose, erythritol, sucralose, and enzyme treated stevia) in milk and instant coffee systems. Additionally, the effects of interactions with other ingredients on the sensory characteristics of milk and coffee were explored. In the case of a banana-flavored milk system, sucrose was added to a concentration of 5%, and the five types of sweetener were added to a concentration of equal sweetness to a 5% concentration of sucrose. For coffee systems, 5.9% sucrose level and sweeteners' concentration equivalent to this level was added. A generic descriptive analysis was performed using ten trained panelists. The results showed that the relative sweetness of all the sweeteners was identical to that identified in the aqueous system, except for stevia in the milk system and in the coffee system with added vegetable cream. For the black coffee system, the relative sweetness decreased for tagatose, erythritol and for stevia. Fat and vegetable cream significantly affected the sensory qualities of milk and coffee, respectively.
Effect of Light Emitting Diode and Fluorescent Light on Volatile Profiles of Soybean Oil during Storage
Park, In-Seon ; Choi, Duck-Joo ; Youn, Aye-Ree ; Lee, Youn-Jung ; Kim, Youn-Kyeong ; Kim, Mun-Ho ; Choi, So-Rye ; Kim, Ki Hwa ; Dong, Hyemin ; Han, Hyun Jung ; Noh, Bong Soo ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 763~769
DOI : 10.9721/KJFST.2013.45.6.763
Soybean oil was stored in polyethylene for 12 weeks at
. The influence of LED (light emitting diode) irradiation on four different wavelengths and fluorescent light was investigated. The pattern changes of volatile components in soybean oil was analyzed by electronic nose based on mass spectrometer. The obtained data from electronic nose were analyzed by discrimination function analysis. Under fluorescent light, the discriminant function first score (DF1) was significantly moved from positive position to negative one after 4-12 weeks. It means that the volatile compounds related to quality of lipid. It was shown to increase slowly due to green light of LED treatment, while blue and white LED light was influenced significantly as well as fluorescent light irradiation. Selection of LED irradiation would provide to keep good quality of soybean oil under distribution chain system.
Antioxidant and Anti-cancer Activities of Squash (Cucurbita moschata Duch.) Leaf Extract In vitro
Kwak, Youngeun ; Ju, Jihyeung ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 770~776
DOI : 10.9721/KJFST.2013.45.6.770
The aim of this study was to investigate the antioxidant and anti-cancer activities of squash leaf extract (SLE) in vitro. The total polyphenol and flavonoid levels of SLE were 263.4 mg gallic acid equivalent/100 g and 73.6 mg quercetin equivalent/100 g, respectively. The radical-scavenging activity of SLE at the concentration of 300
was 69.4%. SLE significantly inhibited human cancer cell growth (by 60.6-87.9% in HCT116 colon cancer cells and by 73.4-86.4% in H1299 lung cancer cells at the concentrations of 37.5, 75, and 150
) and attachment (by 28.4% in HCT116 and by 16.8% in H1299 at the concentration of 150
). SLE also altered nucleus morphology and increased nuclear staining intensity (by 42.8-58.2% in HCT116 and by 25.5-32.9% in H1299 at the concentrations of 37.5 and 75
), indicating its apoptosis-inducing activity. These results demonstrate the antioxidant and anti-cancer activities of SLE in vitro.
Isolation and Identification of Antioxidants from Methanol Extract of Sword Bean (Canavalia gladiata)
Kim, Jong-Pil ; Lee, Hyang-Hee ; Moon, Jae-Hak ; Ha, Dong-Ryong ; Kim, Eun-Sun ; Kim, Jin-Hwan ; Seo, Kye-Won ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 777~784
DOI : 10.9721/KJFST.2013.45.6.777
The ethyl acetate (EtOAc) layer of Canavalia gladiata (sword bean) methanol extracts showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity than other layers. Four phenolic compounds were isolated from the EtOAc layer by silica gel column chromatography and prep-HPLC using a guided DPPH radical-scavenging assay. The isolated compounds were identified as methyl gallate (1), gallic acid (2), 1,6-di-O-galloyl
-glucopyranoside (3), and 1,4,6-tri-O-galloyl
-glucopyranoside (4) based on MS and NMR analyses. Among the four compounds, no. 4 was isolated from this plant for the first time. Their DPPH radical-scavenging activities based on
decreased in the following order: 4 (6.9
Investigation of Hazards from Onions and Their Cultivation Areas to Establish a Good Agricultural Practices (GAP) Model
Choi, Young-Dong ; Lee, Chae-Won ; Kim, Jeong-Sook ; Chung, Duck-Hwa ; Shim, Won-Bo ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 785~790
DOI : 10.9721/KJFST.2013.45.6.785
The purpose of this study was to investigate the hazards from onions and their cultivation areas. A total of 32 samples were collected from onion farms and tested for biological (sanitary indicators, and pathogenic bacteria and fungi) and chemical (heavy metals and pesticide residues) hazards. Aerobic bacteria and coliforms were detected at a level of 0.2-7.1 log CFU/g (or mL) in the soil and agricultural water, 1.6-3.6 log CFU/g on surface of the onion, 0.0-6.0 log CFU/hand (or
) on the workers' hands, clothes, and gloves, and 4.7 log
on the onion bags. Fungi were detected at a level of 0.0-5.0 log CFU/g (or mL, hand, or 100
) in all the samples. Staphylococcus aureus was detected at a level of 1.2 log CFU/hand on the workers' hands, the detection level of Bacillus cereus was up to 4.8 log CFU/g in the soil. However, Escherichia coli (and in particular strain O157:H7), Listeria monocytogenes, and Salmonella spp. were not detected. Although heavy metals were detected in the environment (in soil and agricultural water) and pesticide residues were detected in onion, the levels were lower than the regulation limits.
Evaluation of a PCR Assay for the Rapid Detection of Staphylococcus aureus in Milk and Meat Products
Kim, Hong-Seok ; Chon, Jung-Whan ; Kim, Dong-Hyeon ; Song, Kwang-Young ; Seo, Kun-Ho ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 791~795
DOI : 10.9721/KJFST.2013.45.6.791
The aim of this study was to compare the performance of a standard culture method and polymerase chain reaction (PCR) for the detection of Staphylococcus aureus (S. aureus) in milk and meat products. Milk, dried infant formula, sausage and ground beef that had been artificially inoculated with S. aureus were enriched in tryptic soy broth. After the enrichment, a loopful was inoculated onto Baird-Parker agar with egg-yolk-tellurite. In parallel, 23S rRNA was amplified by PCR from samples of the enriched broth. Suspected S. aureus colonies grown on selective agars were finally confirmed by a coagulase test and colony PCR. No significant statistical differences were observed between the incidence of S. aureus detected by the culture method and the incidence detected by PCR, in milk or dried infant formula. However, in sausage and ground beef, the number of positives detected by PCR was significantly higher than by the culture method (p<0.05). Our findings suggest that PCR could be an effective screening tool for the detection of S. aureus compared to the standard culture method.
Quality Characteristics of Commercial Korean Types of Fermented Soybean Sauces in China
Lee, Sun Young ; Baik, Soo Hwa ; Ahn, Yu Jin ; Song, Jin ; Kim, Jae Hyun ; Choi, Hye Sun ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 796~800
DOI : 10.9721/KJFST.2013.45.6.796
Soybean-based fermented foods have been used as traditional condiments in Korea, Japan and China. Thirteen Korean types of soybean sauce that had been manufactured and sold in China were examined to evaluate their quality. The pH, salinity, and moisture content of the samples were pH 5.17-6.86, 8.0%-23.0%, and 46.446-70.40%, respectively. The amino-type nitrogen content was in the range of 199.18 to 736.46 mg%. The total aerobic bacterial counts were 4.83-7.89 Log CFU/g. The coliform count of gochujang (CNH-2) was 2.31 Log CFU/g, but none were detected in the other samples. Moreover, Bacillus cereus counts from samples of doenjang and gochujang were in the range 2.00-4.09 Log CFU/g. The protease and amylase activity of samples were 379.02-781.36 unit/g and 5.29-63.27 unit/g, respectively.
Production of Glutathione by the Yeast Mutant Saccharomyces cerevisiae Sa59
Jang, Hye-Yoon ; Oh, Chul-Hwan ; Oh, Nam-Soon ;
Korean Journal of Food Science and Technology, volume 45, issue 6, 2013, Pages 801~804
DOI : 10.9721/KJFST.2013.45.6.801
The glutathione contents of the selected mutants were investigated and found to be 6.1-15.8 mg/g-DCW. The glutathione content positively correlated with the antioxidant activity of the mutant strains (
=0.488). Furthermore, the glutathione content of the mutant S. cerevisiae Sa-59 was approximately 38% greater than that of the wild type strain and, therefore, this mutant strain was selected for glutathione production. The volumetric glutathione content in a shaking culture was increased by about 70% compared to the static culture. In addition, the specific glutathione content was increased by ~19%. The volumetric glutathione content and specific glutathione content were increased by approximately 16% and 66%, respectively, when 0.04% glutamate, 0.04% cysteine and 0.04% glycine were added. Furthermore, the highest antioxidant activity was 0.52 as absorbance unit at 700 nm.