• Journal of the Economic Geographical Society of Korea
• /
• v.20 no.2
• /
• pp.121-136
• /
• 2017

In this paper, using trade data of 57 HS 4 digit based agricultural and food(agro-food) products among 47 countries during 2005 to 2014, the international competitiveness and trade structure have been analyzed from the context of global networks employing the methods of social network analysis. Firstly, the differences in the network structure by agricultural products have been revealed. The number of disconnected groups was significantly lager in order of vegetables, fruits and processed foods. Secondly, the differences in the community structure by agricultural and food products have been also revealed. That is to say, for some commodities, the community structure has been changed dynamically, on the other hand, there are some agricultural products that have not changed its community structure despite the increasing trends of trade volume. Thirdly, even though the international competitiveness of Korea's agricultural products was still very limited in the sense that only 26 items have been included in the top3 network of 57 agricultural products, there has been possibilities of the increasing patterns of the competitiveness.

• Microbiology and Biotechnology Letters
• /
• v.43 no.3
• /
• pp.227-235
• /
• 2015

The objective of this study was to improve the quality of Korean rice wine with wild type yeast strains isolated from various traditional Korean fermented foods. Herein the fermentation and sensory characterization of wild yeast, for the purposes of brewing Korean rice wine, was investigated. 12 yeast strains were examined for their ethanol and glucose tolerance. In addition, the pH, soluble solids, acidity, amino acidity, ethanol content, organic acids, and volatile compounds were also studied for the alcoholic beverages made with the wild yeasts. Almost all Saccharomyces genera yeasts were showed to have a tolerance at 10% ethanol, but non-Saccharomyces genera yeasts displayed a low tolerance. The alcoholic beverages fermented by non-Saccharomyces yeasts demonstrated higher levels of soluble solids, titratable acidity, amino acids, and lower ethanol content, when compared with the alcoholic beverages fermented by Saccharomyces genera yeasts. The organic acid content, such as malic acid, acetic acid, and succinic acid, was seen to also be higher. The electronic nose was analyzed, and discriminant function analysis (DFA) was used for discriminating wild yeast strains. The DFA plots indicated a significant separation of Saccharomyces genera and non-Saccharomyces yeast strains. For volatile compounds, ethyl acetate from non-Saccharomyces yeasts, and ethanol from Saccharomyces genera yeast, a high area ratio was observed.

• Food Science and Preservation
• /
• v.21 no.3
• /
• pp.442-450
• /
• 2014

In this study, we isolated a cellulase-producing bacterium isolated from traditional Korean fermented soybean paste and investigated the effect of culture conditions on the production of cellulase. This bacterium, which was identified as Bacillus subtilis 4-1 through 16S rRNA gene sequence analysis, showed the highest cellulase activity when the cells were grown at $45^{\circ}C$ for 24 hours in the CMC medium supplemented with 1.0% of soluble starch and 0.1% yeast extract. The initial optimum pH of the medium was observed in the range of 5.0~9.0. The optimal pH and temperature for the production of cellulase from B. subtilis 4-1 were pH 9.0 and $60^{\circ}C$ respectively. In addition, the enzyme showed significant activity in the temperature range of $20{\sim}90^{\circ}C$, which indicates that B. subtilis 4-1 cellulase is an alkaline-resistance and thermo-stable enzyme. This enzyme showed higher activity with CMC as the substrate for endo-type cellulase than avicel or pNPG as the exo-type substrates for exo-type cellulase and ${\beta}$-glucosidase. These results suggest that the cellulase produced from B. subtilis 4-1 is a complex enzyme rather than a mono-enzyme.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.3
• /
• pp.363-369
• /
• 2015

We investigated the effect of harvesting time on the proximate compositions and biological activities of Lactuca indica L. Seonhyang and wild species. The highest moisture content (91%) was obtained from Seonhyang harvested in June. The wild species harvested in August showed the highest crude protein (4.8%) and crude fiber contents (2.7%). Potassium contents were 626~684 mg/100 g, and no significant difference in harvesting time was observed between Seonhyang and wild species. Calcium and phosphate contents of Seonhyang leaves harvested in August were highest (350 mg/100 g and 123 mg/100 g, respectively). The highest total polyphenol and total flavonoid contents were observed for wild species harvested in June (60 mg/g and 126 mg/g, respectively). Ethanol extracts of Seonhyang and wild species leaves harvested in June showed the highest DPPH radical scavenging activity (95%). ${\alpha}$-Amylase inhibitory activity was highest (94.8%) in water extract of Seonhyang leaves harvested in July. Nitric oxide production inhibitory activity was $14.3{\mu}M$ in ethanol extracts of Seonhyang and $16.8{\mu}M$ in ethanol extracts of wild species harvested in June. Calcium content and ${\alpha}$-amylase inhibitory activity of Seonhyang leaves were greater than those of wild species leaves. These results suggest that Seonhyang leaf can be used to develop processed foods.

• Food Science and Preservation
• /
• v.22 no.6
• /
• pp.908-914
• /
• 2015

The objectives of this study were to isolate and characterize low temperature adaptation yeast and to obtain suitable yeasts strains for manufacturing Yakju. In this study, we isolated 482 wild yeasts from fermented foods. Out of these, 5 yeast strains were selected based on increased growth at low temperature ($15^{\circ}C$) and high ${\beta}$-glucosidase activity. To screen the aromatic level of isolates, media containing cerulenin and 5,5,5-trifluor-DL-leucine (TFL) were used. Y297 strain demonstrated tolerance against TFL and produced more than 13% alcohol. Y297 strain was identified a Saccharomyces cerevisiae based on the 26S rDNA gene sequences. Maximum cell growth was observed after 19 hr and 38 hr of incubation at $25^{\circ}C$ and $15^{\circ}C$, respectively. The exponential phase was followed by a lengthy stationary phase, at $15^{\circ}C$, when the cells remained high viable. Y297 strain demonstrated tolerance against alcohol (10%), glucose (60%) and salt(NaCl, 8%). ${\beta}$-glucosidase and esterase activity in Y297 were higher than those of controls at $15^{\circ}C$. Overall, these results indicated that using wild yeast strain, isolated from fermented food, affects the chemical characteristics of the brewed Yakju.

• Food Science and Preservation
• /
• v.24 no.6
• /
• pp.820-826
• /
• 2017

Soybean is one of the most common food materials for making traditional Korean foods such as soybean paste, soy source and soy snack, and their manufacturing processes include heat treatment of soybean. This study was carried out to investigate the effect of heat treatment on the physicochemical properties of soybean. All samples were heat treated under commercial steamed, puffed or air-fried conditions, and then the protein molecular weight distribution, thermal properties, fluorescence intensity, protein solubility, and water and oil holding ability of the heat treated soybeans were examined. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that heat treatment caused fragmentation of polypeptide chain in soybean, showing the band of low molecular ranging from 17 to 40 kDa. The differential scanning calorimetric analysis showed the decrease of enthalpy values (${\Delta}H$) by heat treatment. Fluorescence spectroscopy indicated that the heat treatment caused lipid oxidation as proved by increasing emission intensity. The protein solubility at pH 3-6, and water holding capacity of heat treated soybeans were the higher than no treatment. These results suggest that the heat treatment resulted in decreased enthalpy values, and increased protein degradation, lipid oxidation and water affinity of soybean. Moreover, the effect of heat treatment on physiochemical properties of soybeans was more significant under air-fried condition.

• Journal of Nutrition and Health
• /
• v.54 no.2
• /
• pp.199-210
• /
• 2021

Purpose: This study investigated the food consumption behaviors in Korean adults, according to the agrifood consumer competency index (ACCI). Methods: Data obtained from the 2019 Consumption Behaviors Survey for Food were analyzed. A total of 6,176 adults (2,783 males, 3,393 females) aged ≥ 19 years, were included in the study. Based on the score of agrifood consumer competency index, the subjects were classified into three groups. The dietary habits, eating-out and food-delivery/take-out behaviors, opinion of food labeling, and concerns for domestic products were compared among the 3 groups. Results: The ACCI scores of the male and female subjects were 63.6 and 64.8, respectively. Subjects of both genders in the highest tertile of the ACCI were more likely to have a higher education level and higher health concerns, as compared to subjects in the lowest tertile (p < 0.05). Male subjects having highest tertile of the ACCI reported significantly more exercise and alcohol consumption, as compared to subjects in the lowest tertile (p < 0.05). A higher score of the ACCI also portrayed a higher satisfaction in own diet and greater checking of the food label. Moreover, subjects with a higher score of the ACCI showed greater satisfaction and reliability in the food label, as well as increased concerns for domestic agrifoods, local foods, and eco-friendly foods. Subjects in the lowest tertile of the ACCI acquired their dietary information from acquaintances, whereas subjects in the highest tertile of the ACCI learnt the information from food labels themselves. Conclusion: These results are indicative of the food consumption and behaviors of Korean adults according to their ACCI scores, and provide basic data that will be useful for implementing an effective food policy.

• Korean Journal of Food Science and Technology
• /
• v.53 no.6
• /
• pp.799-808
• /
• 2021

This study was performed to investigate the extent of microbial contamination, the presence of enterotoxin genes, and the antibiotic susceptibility of Bacillus cereus in 58 red pepper plants and 43 environmental samples (soil, irrigation water, and gloves) associated with the plant cultivation. The detected counts of total aerobic bacteria, coliform bacteria, Escherichia coli, Bacillus cereus, and Staphylococcus aureus were lower in these samples, as compared to the regulations of standards for foods; moreover, pathogens, such as E. coli, E. coli O157:H7, Listeria monocytogenes, and Salmonella spp., were not detected. Genes encoding hemolysin BL enterotoxins (hblA, hblC, and hblD) as well as non-hemolytic enterotoxins (nheA, nheB, and nheC) were detected in 23 B. cereus specimens that were isolated from the test samples and had β-hemolytic activity. Interestingly, B. cereus is resistant to β-lactam and susceptible to non-β-lactam antibiotics. However, in this case, the isolated B. cereus specimens exhibited a shift from resistant to intermediate in response to cefotaxime and from susceptible to intermediate in case of rifampin, trimethoprim-sulfamethoxazole, vancomycin, clindamycin, and erythromycin. Therefore, the levels of B. cereus should be monitored to detect changes in antibiotic susceptibility and guarantee their safety.

• Microbiology and Biotechnology Letters
• /
• v.43 no.1
• /
• pp.56-64
• /
• 2015

It has been known for some time to the wine industry that non-Saccharomyces yeasts play an important role in increasing volatile components through the secretion of extracellular enzymes. The objective of this study was to investigate what types of enzymes are produced by 1,007 non-Saccharomyces yeast strains isolated from Korean fermented foods. Among 1,007 yeast strains, the 566, 45 and 401 strains displayed β-glucosidase, glucanase and protease activity, respectively. In addition, the 563 and 610 strains possessed tolerances against cerulenin and TFL, and the 307 strain was tolerant to 15% ethanol. Yeasts producing harmful biogenic amines and hydrogen sulfide were excluded from further study, and eventually 12 yeast strains belonging to the genera Wickerhamomyces, Hanseniaspora, Pichia, Saccharomyces were identified, based on the 26S rRNA gene sequences. Among the 12 strains, the 9 and 5 strains possessed glucose and ethanol tolerance, respectively. Yeasts belonging to the genus Saccharomyces produced more than 8% alcohol, but non-Saccharomyces yeasts produced only 3% alcohol.

• Journal of Korean Society of Rural Planning
• /
• v.28 no.1
• /
• pp.1-15
• /
• 2022

A Care farm is known to have positive effects on various people in psychological, physical, and social aspects. However, care farm services for the disabled, transportation disadvantaged, and socially disadvantaged are limited. This study conducted a demand survey in order to provide basic data for development of the Agro-Healing Virtual Reality Therapy(AVRT) system. The respondents were the ordinary person(n=127) and the disabled person(n=72), and the survey items consisted of 4 categories and 20 items, including intention to use AVRT, requirements for use, factors to be considered when developing the system, and content and program preferences. The intention to use a AVRT was found to be at a high level of 80% or more by respondent characteristics. In addition, similar results were shown in all items such as virtual reality experience, willingness to use, appropriate use time, and willingness to pay by respondent characteristics, and correlation by item was determined through correlation analysis. As for the conditions of use, both sides preferred rural types and were found to have the purpose of healing. However, there were concerns about dizziness in common between system use, and in the case of the disabled person, there were difficulties in purchasing expensive equipment. In the development of the AVRT system, the part of sensory priority, important technology level, and color preference were evaluated, and the preference of content and programs to be developed in the system was identified. Fruit, vegetables, flowers, and animals preferred mandarin, tomato, tulips, and dogs first, horticultural healing preferred harvest management for the ordinary person, plant cultivation for the disabled person, and forest healing and animal education preferred walking and dog-related programs. However, agricultural work was found to be a program with high preference for making processed foods for the ordinary person and creating an animal breeding environment for the disabled person. The result of this study is expected to provide reference data that can be suggested for the development of Agro-healing Virtual Reality Therapy system.