• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.874-881
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• 2015

In the food industry, thermal treatment is an important process for extending shelf-life of foods. However, heating process affects the physicochemical, nutritional, and microbial properties of foodstuff such as color, texture, pH, and proximate compositions. This study was conducted to select an optimal thermal treatment by observing physicochemical, nutritional, and microbial effects of shiitake mushrooms with different thermal treatment methods. Shiitake mushrooms were washed and sliced equally ($5cm{\times}0.5cm{\times}0.5cm$) and then heat-treated by three methods. Samples were heated in $100^{\circ}C$ boiling water, steamed for 10 min, or pan fried at $130^{\circ}C$ for 4 min. Total color difference values showed significantly increasing tendency with treatment time. For pH values, boiling water-treated mushrooms showed increasing tendency according to increased thermal treatment. For the results of hardness, boiling water or pan frying-treated mushrooms showed reduced tendency within 1 min. In the case of steam-treated mushrooms, hardness values were maintained for 1 min. Organic acid contents of steam-treated sample showed the lowest value among treatments. For microbial counts, steam-treated samples for 3 min showed the lowest value. Consequently, the results of this study suggest that steam treatment could be the optimal thermal treatment to minimize quality loss of shiitake mushrooms.

• Journal of Naturopathy
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• v.10 no.1
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• pp.42-47
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• 2021

Purpose: This study investigated the antioxidant activities of water extracts from Hibiscus petals, Moringa oleifera gymnosperm, and Nipa fruticans wurmb. Also, the possibility of their use as a functional cosmetic material and food were searched. Methods: We extracted Hibiscus petals, M. oleifera gymnosperm, and N. fruticans wurmb with water. And then, we measured the content of total polyphenols and flavonoids and the ability to scavenging free groups of ABTS and DPPH to study the antioxidant function. The toxicity of samples evaluated by measuring cell viability. Results: The polyphenol content of the water extract of N. fruticans wurmb was 109 ㎍/mg, which was significantly higher than that of Hibiscus petals (13 ㎍/mg) and M. oleifera gymnosperm (19 ㎍/mg). Radical scavenging ability was also excellent in N. fruticans wurmb, and the cytotoxicity test results of the samples were similar. Conclusions: The water extracts showed antioxidant activity to use for cosmetic materials or natural healing foodstuff.

• Journal of the Korean Society of Food Culture
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• v.24 no.6
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• pp.613-630
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• 2009

This thesis, which involves honest life stories of members of the ìtraditionalî Korean generation that lived through the turbulent times of the first half of the twentieth century, assesses the meaning and import of Korean cuisine during an individual Korean's lifetime, as well as the relevant properties of the culinary culture of the traditional generation and how those properties continue to influence the present generation of Koreans. Thus, traditional Korean culinary culture was subdivided into the following four aspects, each of which were exemplified by representative examples. The first of these is slow-food dietary life, which is exemplified by fermented foods. The development of side dishes (panchan) based on fermentation - kimchi, different types of soy and bean paste, salted seafoods, dishes of dried radish or cucumber slices seasoned with soy sauce, and so on - made the quantitative and qualitative supplementation of food possible for traditional Koreans. The second of these aspects, referred to as friendly dietary life, is exemplified by self-sufficiently produced foods. The system of many species and small production suitable with the season made it possible to produce food from sustainable ecological systems and to maintain locally grown food-cultures, each of which was distinguished from others by a local specialty product. The third aspect of the traditional Korean culinary culture involves the same use of medicinal roots and plant materials for foodstuff, and this is exemplified by the use of foods to cure and prevent diseases. The notion, for example, that 'boiled rice is an invigorant' is characteristic of the notion that diet can function in a preventative medical context, and other similar Korean notions illustrate the importance, also, of the curative properties of food. The fourth and final aspect of traditional Korean culinary culture identified herein is creative dietary life, which can be viewed essentially as a Korean adaptation to the turbulence of life during the early $20^{th}$ century in Korea. This trend is exemplified by many Korean foods that were created in response to foreign influences, such as onions, cabbages, curry, etc. which found their place in overall Korean culture through the age of Japanese settlement, as well as the Korean war.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.212-218
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• 1986

Proteins in Korean rapeseeds, as in many other plantseeds, are usually bound to phytate molecules. These phytate-bound proteins are of little value as foodstuffs because of their poor solubility in digestive systems. Therefore it is necessary to remove phytates from proteins in order to convert these proteins io a useful foodstuff. In the work, an efficient procedure for removal of phytates from defatted Korean rapeseed was found. The influence of pH on the solubility of protein and phytate of rapeseed flour showed that the former was the lowest at pH 5.0 and began to increase as pH further raised. Meanwhile, the latter was the highest at pH 6.0, however, it was decreased abruptly at alkaline pH, especially to content of 1.3% at pH 11.5. The solubility cf protein was relatively high in NaCl aqueous solution at $pH\;6.0{\sim}8.0$, and did not male any noticeable difference depending on NaCl concentration. On the other hand, the solubility of phytate was high at pH of below 6.0 showing an abrupt decrease at pH of above 6.0. The solubility of protein in $CaCl_2$ aqueous solution was highest at $pH\;6.0{\sim}8.0$, however, there was no significant change at the whole range of tested pH of the solution. A maximum solubility of phytate was shown at $pH\;3.0{\sim}4.0$. And it was decreased abruptly at a higher pH of the above range and also decreased at a lower pH with higher $CaCl_2$ concentration. The solubility of phytate in $Na_2SO_3$ aqueous solution was highest at $pH\;5.0{\sim}8.0$. As the concentration goes up the maximum value of solubility was found to move to higher pHs. Depending on the concentration of $Na_2SO_3$, the decreasing pattern was changed in an alkaline solution. The solubility of phytate in the solution containing low concentration of $Ca^{2+}$ ion was low in all treatments at pH of above 7.0 and showed the maximum value at low pH as $Ca^{2+}$ ion concentration increases. The solubility of protein at pH 11.5 showed the highest value in $1mM\;Ca^{2+}$ ion solution.

• Journal of the Korean Geographical Society
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• v.29 no.1
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• pp.46-64
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• 1994

Among every civilized people salt has been recognized as an essential foodstuff to the human society without which even man's survivor is unthinkable. The cultural-anthropological meaning of salt is estimated highly as well, and in geographical perspective salt itself symbolize regional interrelationship. Playing a decisive role in freeing innermost settlement from isolation, salt aiso made a contribution to expanding human habitats. This study tries to reconstruct historica geography of 18th and 19th century surrounding traditional salt-roasting (chayeom). The Joolpo Inlet area which is located on the mid-western coast in Honem Region is selected for study area. Established on the basis of optimum physical geographical conditions such as topography, climate and vegetation, salt-making of Joolpo Inlet area was run dynamically with the sudden turn of events in the 18-19th century which was chacterized as an age of transition from medieval society to modern one. In this paper the writer attempts to clarify mainly following three points: physical conditions and socio-economic background leading to the initiation and later development of roasting of salt in Joolpo Bay; distribution of saltworks; methods of saltmaking. Main points drawn from these analyses can be summarized as follows: of iron pan and cow-drawn tools rendered labour-saving and output growth. 1, Saltworks of Joolpo Inlet area in the 18-19th century were distributed evenly over Kobu, Puan, Mujang and Heungduck counties among which Kobu's was located in Puanmyon - a sort of exclave. All saltworks belonging to above four counties were clasified as most lucrative ones in Honam Region on government archives. In particular, Gumdang saltwork which belongs to Mujang county is noteworthy in that it was first introduced by one Paekje priest in 6th century and therefore it provides a clue to examine the history of salt-roasting of Joolpo Inlet area. In light of the fact that temple or monastery economy, regardless of East and West, has been closely connected with traditional industry, the case of Gumdang is not unusual. 2. The process of saltmaking follows this order: harrowing of salt field exposed to solar heat; construction of saltern mound with saline earth; acquiring of brine by leaching saline earth; roasting of salt. Salterns (saltworks) are consisted with various salt making facilities such as roasting shed, saltern mound, salt field, salt well) salt pit or brine pit) and seawater reservoir. Among them roasting shed which is constructed chiefly with hundreds of pieces of pine tree as a frame and with straw as roof and wall is customarily considered as an unit of saltwork. And inside it is saltpan made of two kinds of materials, that is iron pan or plaster pan. The area attached to one unit of roasting shed is approximately 1 ha, and that of saltern mound is a tenth of it.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.550-556
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• 1985

In order to evaluate the marine mollusc muscle as foodstuff not only from the biochemical aspect but also from the view point of food science, we have analyzed the protein and amino acid compositions of the echiurid (Urechis unicinctus) and sea hare (Aplysia kurodai) muscle. The protein quality of the muscles was also investigated using in vitro methods based on in vitro digestibility, predicted digestibility, computed PER (C-PER) and discriminant computed PER(DC-PER). The remarkable feature of the protein compositions of the both muscles was that water soluble protein occupied a large amount of the muscle protein with fairly lower contents of the salt soluble protein. From the analysis of SDS-PAG electrophoresis, the sarcoplasmic proteins in the echiurid and the sea hare muscles were composed of 15 and 10 subunits, respectively. The free amino acid compositions of the total amino acids in the echiurid and sea hare muscle were characterized with $75\%$ of glycine and alanine, and with $78\%$ of taurine, respectively. The amino acid anaylsis of both muscle proteins showed that the echiurid muscle was rich in glycine, aspartic acid, glutamic acid, arginine and lysine, but was poor in cysteine, while the sea hare muscle was rich in glycine, glutamic acid, aspartic acid and arginine, but was negligible in cysteine and tryptophan. In the total amino acid profiles of the freeze dried muscles in echiurid and sea hare, there was not found a significant difference compared to the amino acid compositions of the muscle proteins. Predicting the protein quality of the echiurid and sea hare muscles using the in vitro method, it was apparently low compared to the muscle protein of fishes.

• Korean Journal of Environmental Agriculture
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• v.23 no.1
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• pp.52-58
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• 2004

This work was conducted to provide the reference data of radioactivity in the foodstuffs at a radiological emergency situation in Jeju Island The sampled foodstuffs were agricultural (31), livestock (6), marine (12) and forest products (4), and processed foods (3) consumed by Jeju Islanders. $^{137}Cs$ and $^{40}K$ activities were determined by HPGe r-ray spectromety. The activity ranges of $^{137}Cs$ was ${\sim}650\;mBq/kg$ fresh in the agricultural products, ${\sim}131\;mBq/kg$. fresh in the livestock, ${\sim}834\;mBq/kg$ fresh in the forest, ${\sim}253\;mBq/kg$ fresh in the marine and $32.0{\sim}483\;mBq/kg$. fresh in the processed foods (tea). In case of $^{40}K$ the activity was $16.6{\sim}542\;Bq/kg$. fresh in the agricultural products, $39.1{\sim}294\;Bq/kg$ fresh in the livestock, $85.5{\sim}116\;Bq/kg$ fresh in the forest, $50.1{\sim}657\;Bq/kg$ fresh in the marine, and $33.6{\sim}1,065\;Bq/kg$ fresh in the processed foods (tea). The highest activity of $^{137}Cs$, 834mBq/kg fresh was observed in oak mushroom and $^{40}K$ 1,065 Bq/kg fresh in coffee. Annual effective doses of $^{137}Cs$ and $^{40}K$ by intake of foodstuffs per capita were the following order; agricultural products (66,543 nSv) > livestock products (19,311 nSv) > processed foods (6,648 nSv) > marine products (6,579 nSv) > forest products (860 nSv). Therefore, total annual effective dose was summed 99,941 nSv which is quite low level comparing to the annual effective dose by external exposure, 2,400,000 nSv. The data obtained in this study can be useful for monitoring whether the foodstuffs are contaminated or not at an emergency radiation accident, and showed that the foodstuffs consumed in Jeju are safe in terms of annual effective dose of $^{137}Cs$ and $^{40}K$

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.333-338
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• 2008

The tea has traditionally been used as a foodstuff by unique flavor, however recently not only the diversity of consumer demands but also the public interest in unique favorite and functional aspects have increased. It has been also reported that the main components contained in the leaves of tea (Camellia sinensis) include total nitrogen, free amino acids, polyphenols, and fiber, of which catechin has powerful bioactive effect such as anti-cancer, anti-aging, and anti-diabetic. (-)-Epigallocatechin gallate (EGCG) which is a major phenolic constituent of green tea extract has received considerable attention for a variety of important bioactivities. This study was carried out to obtain useful information for tea breeding programs, and to investigate the concentration of quality and functional related components in Korean indigenous tea germplasms. Korean indigenous tea lines were classified into three groups of sprout time, i.e, early, medium and late sprout time, and the ratio were 20%, 43% and 37%, respectively. There was a difference in characteristics among these Korean indigenous tea lines, leaf width of those ranged from 19.8 to 75 mm, leaf length was 35.5-160.0 mm, and leaf area was $660-8,400\;mm^2$. Experimental data on chlorophyll content (SPAD value) of Korean indigenous tea genetic resources ranged from 51.3 to 82.3. The concentrations of the total nitrogen, total free amino acids, and theanine were ranged 4.18-6.07%, 2.87-4.58%, and 1.64-2.66%, respectively. Also, catechin concentration showed from 11.54 to 15.07%, and concentration of caffeine was 2.82-4.23%. These results indicated indicated that it is possible to select elite lines with high concentration of quality related components and low concentration of caffeine from Korean domestic tea germplasms.