• Korean Journal of Food Science and Technology
• /
• v.33 no.5
• /
• pp.589-595
• /
• 2001

Effect of anti-microbial agents, such as alcohol, garlic, chitosan, K-sorbate, or mustard, or pasteurization on the quality of traditional kochujang was investigated during storage at $30^{\circ}C$ for 24 weeks. Water activities of kochujang decreased after 12 weeks of storage. Consistency increased during storage and highest consistency of kochujang was obtained by the addition of mustard or garlic. Hunter a- and b-values decreased linearly as storage time passed. The degree of increase in total color difference$({\Delta}E)$ of alcohol added group was the highest among the tested anti-microbial agents. Gas was rapidly produced in the control and chitosan added group of kochujang. Capsanthin content decreased more rapidly in the group of alcohol, garlic or mustard added kochujang than the other group. Viable cell counts of yeast and aerobic bacteria in kochujang increased up to 12 weeks of storage, and then decreased slowly. The number of yeast was low in K-sorbate or alcohol added group. Activity of ${\alpha}-amylase$ decreased during storage, but that of ${\beta}-amylase$ increased in alcohol, garlic, K-sorbate added or pasteurized kochujang. Protease activities did not show any remarkable differences in the groups of tested during storage.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.6
• /
• pp.1050-1057
• /
• 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
• /
• v.15 no.5
• /
• pp.648-655
• /
• 2008

A gamma irradiation process was applied to prolong the shelf-life of grapes and changes in microbiological, physicochemical, nutritional, and sensory characteristics were investigated during 6 weeks of post-irradiation storage at $4^{\circ}C$ and $25^{\circ}C$. Physiochemical characteristics of grapes such as total sugar content, pH, titratable acidity, and anthocyanine content, were stable after 1 kGy of irradiation, a dose recommended by CODEX for fruits and vegetables. The viable cell counts of contaminating microorganisms were reduced 1-2 logs by this radiation dose. After 6 weeks of storage at $4^{\circ}C$ the microbiological quality of irradiated grapes was stable, but all non-irradiated grapes had deteriorated. Whether or not grapes were irradiated, weight loss rapidly increased after 2 weeks of storage at $25^{\circ}C$, whereas weight loss was delayed by storage at $4^{\circ}C$. Immediately after gamma irradiation, the sensory evaluation results did not differ between samples, and the sensory quality of the irradiated grapes remained acceptable for over 6 weeks of storage at $4^{\circ}C$. The results suggest that 1 kGy of gamma irradiation does not detrimentally affect the nutritional or physical characteristics of grapes, especially when cold storage follows radiation treatment. In conclusion, a combination of gamma irradiation and cold storage prolonged the shelf-life of grapes by 6 weeks.

• Food Science and Preservation
• /
• v.18 no.3
• /
• pp.288-293
• /
• 2011

This study investigated the changes in the quality of fresh-cut lotus roots that were treated with hot water. Lotus roots were purchased from Daegu, Korea. They were washed, peeled, and cut into lcm-thick slices with a ceramic knife. The peeled and sliced lotus roots were dipped for 45 sec in water at 30, 55, and $80^{\circ}C$. After they were air-dried at room temperature, the slices were packed in polyethylene films and stored at $4^{\circ}C$ for 12 d. Then the changes in the weight loss, color, total viable cell, and sensory characteristics were measured. Generally, the weight loss of the lotus roots that were treated with hot water slightly increased. The application of the heat treatment delayed the browning of the lotus roots, especially the treatment with $55^{\circ}C$ hot water. The L and a values of the lotus roots that were treated with $80^{\circ}C$ hot water significantly increased during their storage, though. The heat treatment effectively inhibited the growth of microorganisms. The organoleptic quality of the lotus roots that were treated with $55^{\circ}C$ hot water was the best.

• Korean Journal of Food Science and Technology
• /
• v.53 no.6
• /
• pp.761-767
• /
• 2021

Strawberries fermented with Acetobacter pasteurianus SRCM60009 were prepared, and the quality characteristics and physiological activity were measured. As the fermentation period increased, viable cell counts increased, pH decreased, and total acidity increased from 1.09% to 4.20%. The organic acid content of strawberry through acetic acid fermentation was confirmed in the following order: acetic acid, succinic acid, citric acid, and lactic acid. Measurement of α-glucosidase and pancreatic lipase inhibitory activities and angiotensin converting enzyme inhibitory activity showed significantly increased physiological activity owing to fermentation. The use of strawberry vinegar as a functional material was confirmed by measuring the anti-diabetic, anti-obesity, and anti-hypertensive physiological activities through acetic acid fermentation of strawberry. Thus, fermented strawberry vinegar can be used as a functional material in vinegar and other foods.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.2
• /
• pp.5-15
• /
• 2020

To extend the shelf life of draft makgeolli, UV irradiation and high hydrostatic pressure were conducted. UV irradiation did not reduce the total cell number in makgeolli, but high hydrostatic pressure treated drastically decreased. The number of viable cells in makgeolli was 2.2-5.8 × 10⁷ CFU/mL, but when treated with 300 MPa pressure for 1 minute, it decreased to 1.4-10 × 10³ CFU/mL, with 400 MPa to 4-68 CFU/mL, and with 500 MPa to under 40 CFU/mL. Yeast died at 400 MPa pressure, but Bacillus amyloliquefaciens and Rummeliibacillus stabekisii survived at 500 MPa pressure. The makgeolli treated with 400 and 500 MPa pressure did not increase the number of cells even when stored at room temperature (25℃) for 30 days, and changes in alcohol, acidity, and amino acid vlaue were also suppressed. However, when stored for more than 30 days at room temperature, the acidity and amino acid levels of makgeolli increased, making it difficult to drink. At low temperature (4℃) storage, the quality change of makgeolli was suppressed until 70 days of storage, so it had a taste similar to that of fresh makgeolli.

• Korean Journal of Veterinary Service
• /
• v.45 no.3
• /
• pp.155-164
• /
• 2022

This study was conducted for safety evaluation on 130 pet food products, which are distributed in Gwangju, South Korea. The microbial contamination part and the usage of food additives part were mainly investigated. The five microorganisms that we tested were total viable cell counts (TVC), Coliforms, Salmonella spp., Campylobacter spp., pathogenic Escherichia coli and there were 15 products that exceed the microbial criteria or detected food poisoning bacteria. Specifically, Coliforms (13 products, 10%), TVC (9 products, 6.9%), Salmonella spp. (2 products, 1.5%), and E. coli (2 products, 1.5%) were followed. On the other hand, food additives such as preservatives, antioxidants and sodium nitrite were detected in 61 products. Among the preservatives, sorbic acid and benzoic acid were detected in 58 (44.6%) products. In antioxidants, Butylated hydroxytoluene (BHT) was detected in 3 (2.3%) products. In addition, preservatives and antioxidants were detected in 8 of 20 products labeled as 'additive-free'. Microbial contamination tended to occur mainly in small-scale individual homemade feed stores, while food additives were all detected in pet shops and supermarkets. Currently, the criteria for microorganisms and food additives for pet foods are insufficient in Korea. So, it is necessary to establish detailed feed standards and specifications for companion animals.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.2
• /
• pp.131-142
• /
• 1989

As a part of investigation for utilizing anchovy more effectively as a food source, this work was undertaken the changes in keeping quality and taste compounds in the extracts from rapid fermented anchovy sauce during storage at room temperature. Rapid fermented products was made of chopped anchovy, water, koji and soybean protein isolate (20:10:2:1, w/w) thorough hydroxazine for 6 hours at $50^{\circ}C$. The liquified anchovy sauce extracts, contained 15% salt(w/w), were stored for 60 days at room temperature. The changes in pH, acidity, amino nitrogen and contents of taste compounds of the products were negligible during storage. The viable cell counts and histamines of the products were less than 30(colony/e extracts), 7.2-21.8(mg/100g extracts) during storage predominant free amino acids showed in the extracts from products were alanine, glutamic acid, histidine, lysine, leucine, valine and the total contents of those free amino acids were 60.4-64.3% of total free amino acids at final stage of storage. The major nucleotides and their related compounds of the products were revealed hypoxanthine, which were 69% over the total nucleotides and their related compounds. Using the omission test, the major taste compounds in the products were revealed free amino acids, nucleotides and their related compounds. The non-volatile organic acids, total creatinine, betaine, and TMAO were seemed to act an auxiliary role in taste of the extracts from rapid fermented anchovy sauce.

• Radiation Oncology Journal
• /
• v.15 no.3
• /
• pp.175-186
• /
• 1997

Purpose : To evaluate the qualitative immunologic changes by ionizing radiation. we studied the altered capacities of the macrophages and lymphocytes to produce cytokines in conjunction with resistance to Listeria monocytegenes (LM) infection in mice Materials and Methods : BALB/c mice and Listeria monocytogenes were used. The mice were infected intraperitoneally with $10^5LM$ at 1 day after irradiation (300cGy) and sacrificed at 1, 3, 5 days after infection, and then the numbers of viable LM per spleen in the irradiated and control group were counted. Tumor necrosis factor-alpha ($TNF-\alpha$), interferon-gamma ($IFN-\gamma$). interleukin-2 (IL-2), and nitric oxide (NO) were assessed after irradiation. Results : Under gamma-ray irradiation with a dose range of 100-850cGy, the number of total splenocytes decreased markedly in a dose-dependent manner, while peritoneal macrophages did so slightly Cultured peritoneal macrophages produced more $TNF-\alpha$ in the presence of lipopolysaccharide (LPS) during the 24 hours after in vitro irradiation, but their capacity of $TNF-\alpha$ Production showed a decreased tendency at 5 days after in vivo total body irradiation. With 100cGy and 300cGy irradiation, cultured peritoneal macrophages produced more NO in the presence of LPS during the 24 hours after in vitro irradiation than without irradiation. Activated splenocytes from irradiated mice (300cGy) exhibited a decreased capacity to Produce IL-2 and $IFN-\gamma$ with Concavalin-A stimulation at 3 days after irradiation. When BALB/c mice were irradiated to the total body with a dose of 300cGy, they showed enhanced resistance during early innate phase, but a significant inhibition of resistance to LM was found in the late innate and acquired T-cell dependent phases. Conclusion : These results su99es1 that increased early innate and decreased late innate and acquired immunity to LM infection by ionizing radiation (300cGy) may be related to the biphasic altered capacity of the macrophages to produce $TNF-\alpha$ and the decreased capacities of the lymphocytes to produce IL-2 and $IFN-\gamma$ in addition to a marked decrease in the total number of cells.

• The korean journal of orthodontics
• /
• v.31 no.6 s.89
• /
• pp.589-600
• /
• 2001

Insulin-like growth factor I (IGF-I) has the local tissue regulating actions. In bone, IGF-I increases the replication of osteoblastic lineage, probably preosteoblasts, and enhances osteoblastic collagen synthesis and matrix composition rates. The purpose of this study was to investigate the local regulatory effect of IGF-I on periodontium totally, both in an autocrine and paracrine manner. To examine the effect of IGF-I directly on osteoblast (OB) of test rats, and indirectlv on OB via periodontal ligament fibroblast (PDLF), and the effect of gingival fibroblast (GF) on OB via cellular paracrine manner for the understanding of humoral action of adjacent tissue, GF and PDLF were obtained from male Sprague-Dawley rats of six to eight weeks of age. OB was obtained iron frontal and parietal calvarial bone of Sprague-Dawley 21day-old-fetus. After each tell was Incubated 24 hours, for collecting conditioned medium, different concentrations of IGF-I (1,10,100 ng/ml,1ml/well) was adding in the GF, PDLF cells, and the supernatant from these cultures was put into the primary OB culture with $1{\times}10^4$cell/ml/well. The experimental group was divided into six groups control OB, IGF-I treated OB, OB culture with conditioned medium from PDLF, OB culture with conditioned medium from IGF-I treated PDLF, OB culture with conditioned medium from GF, OB culture with conditioned medium from IGF-I treated GF. After final IGF-I treatment, OB was Incubated for 24 hours, and alkaline phosphatase activity assay, BMP expression, cell proliferation measurement using MTT assay, total protein measurement, Collagen synthesis assay using western blot, and examination of bone nodule synthesis were done. Alkaline phosphatase expressions were increased in the group of PDLF-IGF-I supernatant treatment. Direct IGF-I treatment with concentrations of 100ng/m1 showed increased viable tell number measured by MTT assay. And IGF-I treatment did not increase total protein amount. The entire experimental group showed BMP2, 4 expression in western blot, and there was no significant difference between control and experimental groups. These results suggested that supernatant from PDLF effects on increasing cellular activities of OB regardless of IGF-I, and at high concentration, IGF-I increases OB tell proliferation.