• Korean Journal of Food Science and Technology
• /
• v.42 no.4
• /
• pp.420-423
• /
• 2010

The proanthocyanidin fraction was isolated from the wild grape (Vitis amurensis) peel and its antioxidant capacities were examined to promote the utilization of wild grape by-products. The 70% acetone crude extract of the wild grape peel was fractionated with hexane, ethyl acetate, and water. The ethyl acetate fraction was applied to a Sephadex LH-20 column chromatograph, which was eluted with 50% methanol, 75% methanol, and 75% acetone. The proanthocyanidin characteristics and contents of the isolated fractions were investigated by the vanillin-$H_2SO_4$ and BuOH-HCl methods. Fraction 6 had the highest proanthocyanidin content ($49.35{\pm}2.75\;g%$) among the isolated fractions. The antioxidant activities of the proanthocyanidin fraction were examined by DPPH radical scavenging, FRAP assay, and total phenolic contents. The FRAP values and total phenolic contents of the fractions ranged from 3.54 to 32.25 mmol/kg and from 4.48 to 50.80 g/100 g, respectively. The proanthocyanidin contents was strongly correlated with DPPH radical scavenging activities, FRAP values, and total phenolic contents.

• Korean Journal of Food Science and Technology
• /
• v.48 no.1
• /
• pp.42-47
• /
• 2016

The purpose of this study was to evaluate the quality characteristics in different types of Omija (Schizandra chinensis Baillon) powder tea. Raw Omija was prepared in three ways: 1) freeze-dried powder of whole Omija (FD), 2) freeze-dried powder of pressed Omija juice (PF), and 3) granules of pressed Omija juice (PG). Dried Omija was extracted and prepared in three ways: 4) freeze-dried powder (EF), 5) granules (EG), and 6) spray-dried powder (ES). The total soluble solid contents and turbidity were higher in PG, EG, and ES than those in other samples. $L^*$ value, pH, and reducing sugar contents were higher in PG and EG than those in other samples. Finally, $a^*$ value, $b^*$ value, total phenolic compounds contents, antioxidant activities, total anthocyanin contents, and schizandrin contents were lower in PG and EG than those in other samples. These results show that FD, PF, EF, and ES are more effective in outstanding redness and antioxidant activities compared to other Omija powder products.

• The Korean Journal of Food And Nutrition
• /
• v.27 no.2
• /
• pp.302-309
• /
• 2014

In this study, the characteristics of soybeans with different cultivation methods depending on their origins and the properties of tofu made from these soybeans were studied. The isoflavone content was higher in the general Korean soybeans compared to the organic American soybeans. There were no significant differences among the Chinese soybean samples, so the cultivar method was considered to have a greater effect on the isoflavone contents rather than the cultivation method. The protein contents were higher in the tofu made from the general Chinese soybeans and the organic Korean soybeans. Furthermore, the tofu made from the organic Chinese soybeans contained the least amount of proteins. Isoflavone contents were not significantly different among the samples. Texture profile analyses consisting of hardness, cohesiveness, adhesiveness, springiness, and gumminess were all shown to be higher in the organic tofu than in general tofu, with the exception of adhesiveness. In sensory evaluation, color and texture were significantly different according to the samples, and the differences were found to be affected more by the origin of soybeans rather than the cultivation methods. According to this study, the physicochemical properties of the soybeans and tofu seemed to be influenced by the cultivation region rather than the methods.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.9
• /
• pp.1369-1379
• /
• 2014

The physicochemical characteristics and antioxidant activities of leaf, stem, and root of ginger (Zingiber officinale R.) were determined. Nutrient composition, reducing sugar, saponin, mineral, heavy metal, total phenolic and total flavonoid contents, and antioxidant activities based on DPPH radical scavenging and FRAP assay were measured. Catechins, gingerols, shogaols, and capsaicin compositions were also determined by HPLC. The contents of water, proteins, fats, carbohydrates, fiber, and ash from ginger root were 6.4, 6.8, 3.2, 65.4, 7.3, and 18.2%, respectively. Crude fiber contents of leaf and stem were 4~5 times higher than those of root (P<0.05), and reducing sugar content of stem was about 3 times higher than those of root. Crude saponin contents were in the order of stem

• Korean Journal of Food Science and Technology
• /
• v.3 no.1
• /
• pp.15-18
• /
• 1971

The Korean rice of Paldal variety was milled, in March, 1969, into brown rice and 92% polished one and each 1.5kg sample was packed in the kraft paper bags. With Co-60 gamma-irradiation, the samples were treated in the various ranges of 500, 800 and 1,000 Krad, and then they were stored at the room temperature. The changes of the contents of free amino acids in the samples were determined by the amino acid autoanalyzer (Yanagimoto, Japan, LC-type). The results obtained in June and October of the year were as follows. 1) In the disinfecting irradiation of rice by the higher doses of 500, 800 and 1,000 Krad, there wasn't any particular distinction between the control lot and irradiated lot in respect to the free amino acid contents. 2) The contents of free amino acids in rice during storage had the decreasing tendencies, and especially prominent in case of glutamic acid.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.1
• /
• pp.61-68
• /
• 2019

In this study, the contents of water-soluble vitamins $B_1$ (thiamin), $B_2$ (riboflavin), $B_3$ (niacin), and $B_{12}$ (cyanocobalamin) in namuls (wild greens), such as salads and side dishes, consumed in Korea were quantified by high-performance liquid chromatography (HPLC) with UV and fluorescence detection. All samples were prepared with recipes used in Korea. All analyses were performed under the quality control of vitamin $B_1$, $B_2$, $B_3$, and $B_{12}$. The vitamin $B_1$, $B_2$, and $B_3$ contents in namuls consumed in Korea were analyzed. The highest content of vitamin $B_1$ was $3.018{\pm}0.016mg/100g$ in Putgochudoenjang-muchim. The highest contents of vitamin $B_2$, $B_3$, and $B_{12}$ were $0.279{\pm}0.003mg/100g$ in Gul-muchim, $12.241{\pm}0.040mg/100g$ in Chamchi-salad, and $8.133{\pm}0.371{\mu}g/100g$ in Pijogae-muchim, respectively. These results showed that animal-based ingredients in salads provided for good intake of vitamin $B_{12}$. These results can be used as basic data for food composition tables and improvement of the national health of Koreans.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.57 no.2
• /
• pp.186-191
• /
• 2024

In this study, we analyzed the nutritional compositions of five species of flounder inhabiting Korean coastal waters. In terms of proximate composition, the moisture and crude fat contents of flounders ranged from 75.16±0.37 to 79.94±0.09 g/100 g and 0.48±0.02 to 4.07±0.09 g/100 g, respectively, and showed a negative correlation. Crude protein contents among the five species were found to range from 18.74±0.37 to 19.69±0.44 g/100 g and showed no significant inter-species differences. Among these flounders, Clidoderma asperrimum was characterized by the highest crude fat and total fatty acid contents of 4.07±0.09 g/100 g and 2,739.39 mg/100 g, respectively, as well as the highest content of polyunsaturated fatty acids, including EPA and DHA, at 620.24 mg/100 g. Hippoglossoides dubius was found to have a total amino acid content of 18,971.36 mg/100 g. Our finding in this study regarding the nutritional profiles of flounders will provide valuable information for industrial use.

• Fisheries and Aquatic Sciences
• /
• v.10 no.4
• /
• pp.179-185
• /
• 2007

Understanding dietary habits is one of the most important factors in studying food webs and other ecological processes. Here we designed universal primers to amplify portions of the 18S and 28S rDNA sequences to examine gut contents using PCR techniques. The gut contents of sailfin sandfish (Arctoscopus japonicus) and pacific squid (Todarodes pacificus) were examined. In total, 11 families of prey were identified with 18S and 28S rDNA using the universal primers. The DNA sequence data indicated that the primer sets successfully amplified a wide spectrum of species and represented gut contents in a relatively convenient way. We found that information in the NCBI database was not yet sufficient to discriminate the species we isolated. In addition, technology for the separation of heterogeneous PCR products and better resolution and quantification protocols would help increase data accuracy.

• Journal of Food Hygiene and Safety
• /
• v.11 no.1
• /
• pp.1-5
• /
• 1996

This study is performed to identify the contents of nitrosamine in meat (beef, pork) and meat product (ham, bacon, sausage) by gas chromatograph-thermal energy analyzer. The author also determained the formation of nitrosamine in these products when they were cooked in frying pan at 21$0^{\circ}C$ for 4 minutes and microwave for 45 and 75 seconds. N-ni-trosodimethylamine (NDMA) analysis was impossible in the most products because of their impurieties. On the other hand, N-nitrosopyrrolidine (NPYR) of 0~9.4 ug/kg in meat and 0~15.6 ug/kg in meat products were detected, respectively. When meat and meat products were cooked, generally contents of NDMA and NPYR have a tendency to be increased a little. Meat and product being cooked in microwave rather than frying pan, contents of NDMA and NPYR were detected more. Especially, in sausage contained much flsh, contents of NDMA was detected more.

• Journal of Korean Home Economics Education Association
• /
• v.27 no.1
• /
• pp.31-50
• /
• 2015

The purpose of this study was to analyze duplicated contents of 'Food and Nutrition unit' of Home Economics and other subject textbooks for the middle school students. In order to achieve the purpose, the textbooks of "Home Economics I II", "Science I II III", "Ethics I II", "Physical education", and "Health education" were analyzed. The results of the analyses were as follows. According to the analyses of the common contents with other subjects related to the 'Food and Nutrition unit' in the "Home Economics I II" textbooks for the middle school students under the 2009 revised curriculum, the high percentages of the common contents were found in "Science" curriculum and "Health education" curriculum, followed by "Physical education" and "Ethics". It was observed that the Home Economics curriculum provided not only the theoretical basis about the dietary issues that the youth faces but also a plan to address those issues, as "Home Economics" textbooks were focused on 'dietary problems of the youth', 'balanced diet', 'green diet', and 'Korean-style diet'. The "Science" curriculum focused on scientific theories and principles, as the "Physical Education"and the "Health education" focused on health. In contrast, it was revealed that the "Ethics" curriculum considered 'Koreans' identity' and 'environment'. Overall as for the strength of 'Food and Nutrition unit' of "Home Economics"compared to those of other subjects, comprehensive contents for dietary life had been dealt with according to the development of the adolescent in "Home Economics", while other subjects focused on specific contents or examples concerned with 'Food and Nutrition unit'. In this regard, the dietary education for the middle school students will be more effectively conducted by "Home Economics", as compared with other subjects.