• Journal of Life Science
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• v.19 no.9
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• pp.1271-1276
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• 2009

Unlike the traditional preparation method for Chungkukjang, we prepared Dua-Chungkukjang with soybean fermented at $40^{\circ}C$ after the soaking, germination and steaming process, and we studied the physico-chemical characteristics of Dua-Chungkukjang. Reducing sugar content in both traditional Chungkukjang and Dua-Chungkukjang increased sharply after 10 hr of fermentation, but it decreased slightly after that. Total nitrogen content in both traditional Chungkukjang and Dua-Chungkukjang increased slowly as fermentation took place. Total nitrogen content reached 3,500 mg% and 3,700 mg%, and soluble nitrogen compound reached 750 mg% and 1,800 mg% after 40 hr of fermentation, respectively. $\beta$-Glucosidase activity increased continuously as fermentation took place, and it reached 193, 223, 235 and 248 units in Dua-Chungkukjang while it reached 125, 178, 205 and 214 units in traditional Chungkukjang after 10 hr, 20 hr, 30 hr and 40 hr of fermentation. This means that $\beta$-Glucosidase activity in Dua-Chungkukjang was $1.2{\sim}1.5$ times higher than that in the control treatment, traditional Chungkukjang. Total isoflavone content was $101.44{\mu}g$/g and $365.92{\mu}g$/g for 10 hr of fermentation, and $225.98{\mu}g$/g and $441.37{\mu}g$/g for 40 hr in traditional Chungkukjang and Dua-Chungkukjang, respectively. Isoflavone content of Dua-Chungkukjang was 2-3.5 times higher than that of traditional Chungkukjang. Anthocyanin content also increased continuously as fermentation took place, and it reached 5.0 mg/g and 6.9 mg/g in traditional Chungkukjang and Dua-Chungkukjang after 40 hr of fermentation, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.96-101
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• 2013

This study was carried out to investigate the changes in antioxidant activity, and the isoflavone and free amino acid content in fermented tofu of the ingredients of kimchi (red pepper, garlic, ginger, and anchovies) and lactic acid bacteria (Pediococcus acidilactici KL-6) during 24 weeks of fermentation at $20^{\circ}C$. The total polyphenol content of various types of fermented tofu such as the control (tofu with kimchi ingredients mixture), tofu and kimchi ingredients with lactic acid bacteria (TL), and tofu in pre-fermented kimchi ingredients with lactic acid bacteria (TPL) ranged from 156.34 to 165.17 mg/g, showing that TPL was significantly higher in terms of fermentation time (6 weeks) compared to others. The DPPH free radical scavenging activity of TPL (84.11%) was higher than that of the control (76.68%) and TL (78.95%) after 12 weeks fermentation at $20^{\circ}C$. The changes of nitrite scavenging activity and SOD-like activity in the tested tofu showed the same tendency as the DPPH free radical scavenging activity during 14 weeks fermentation TPL showed statistically significant levels of increased antioxidant activity, so we compared the isoflavone and free amino acid content. The isoflavone and free amino acid content of TPL was 2.34 mg/g and 20.81 mg/g after 14 weeks fermentation, respectively.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.331-336
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• 2006

Effects of high temperature and pressure treatment on garlic (Allium sativum L.) treated at 110, 120, 130, 140, and $150^{\circ}C$ for 1, 2, 3, 4, and 5 hr were evaluated by investigating changes in antioxidant activities, and total polyphenol, total flavonoid, and 5-hydroxymethyl-2-furaldehyde (5-HMF) contents of garlic juice. Antioxidant activities, and total polyphenol, total flavonoid, and 5-HMF contents increased with increasing treated temperature and time. $IC_{50}$ (1.952 mg/g) was achieved at $150^{\circ}C$ for 4 hr, 50 times higher than untreated garlics. Highest total polyphenol content was 18.155 mg/g at $140^{\circ}C$ and 2 hr, seven times higher than untreated garlics. Highest total flavonoid content was $532.73\;{\mu}g/g$ at $150^{\circ}C$ and 1 hr, sixteen times higher than untreated garlics. 5-HMF content was highest (7,765.9 ppm) at $150^{\circ}C$ and 2 hr. Correlation coefficients among antioxidant activities, and total polyphenol, total flavonoid, and 5-HMF contents were very high (p<0.01).

• Food Science and Preservation
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• v.30 no.1
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• pp.1-14
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• 2023

In this study, the nutritional compounds present in various parts of Hovenia dulcis Thunbergii (H. dulcis) were compared. Regarding the free sugar content, fruits exhibited the highest fructose concentration (9.42 g/100 g), whereas branches (2.46 g/100 g) and leaves (5.82 g/100 g) contained the highest glucose levels. The most common types of organic acids were citric and tartaric acids in the fruits, citric and malic acids in the branches, and malic and succinic acids in the leaves. The leaves exhibited the highest total amino acid content of 12,102.91 mg/100 g, whereas vitamin C is predominantly found in branches and leaves at 367.85 mg/100 g and 336.21 mg/100 g, respectively. In H. dulcis, β-carotene was present in high concentration in leaves (2.41 mg/100 g), whereas the branches (0.15 mg/100 g) and fruits (0.09 mg/100 g) contain smaller amounts of it. Vitamin E, α-tocopherol, was present in high concentrations in the fruit (11.01 mg/100 g), branches (6.61 mg/100 g), and leaves (11.01 mg/100 g).

• Journal of Mushroom
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• v.20 no.4
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• pp.227-234
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• 2022

This study analyzed Tuber melanosporum, Tuber aestivum,and Tuber magnatum, specifically the content of 𝛽-glucan, amino acids, nucleic acid-related substances, vitamin C, and ergosterol. The 𝛽-glucan content was highest in T. magnatum (20.54%). The free amino acid content was highest in T. aestivum, with the major amino acids being cystine, glutamic acid, and aspartic acid. The total amino acid content was the highest in T. magnatum, the primary amino acids being cystine, glutamic acid, and lysine. The content of nucleotide related compounds was the highest in T. magnatum (5.09 mg/100 g). The highest content of vitamin C (10.15 mg/100 g) and ergosterol (596.91 mg/100 g) was found in T. magnatum, which had the highest useful component content among the three truffles. Additional studies investigating the variation in useful components according to collection time and growth environment are needed.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1387-1390
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• 2008

This study evaluated the effects of heat treatment on antioxidant activity of Rehmannia radix Libosch (RRL). RRL was heated at various temperatures ($110-150^{\circ}C$) for various times (1-5 hr), and the total polyphenol, flavonoid content, and antioxidant activity were investigated. With increased heating temperature and exposure time, total content of polyphenol, flavonoid, as well as antioxidant activity increased. The highest total polyphenol and flavonoid contents were 21.65 and 3.56 mg/g, respectively, these values were occurred after heating for 3 hr at $150^{\circ}C$ (RRL was 5.09 and 0.83 mg/g, respectively). The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was highest value of 83.46% after heating for 3hr at $150^{\circ}C$. The 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) cation radical scavenging activity was highest value of 20.43mg ascorbic acid (AA) eq/g after heating for 2 hr at $150^{\circ}C$. There were highly significant differences in the total polyphenol, flavonoid content, and antioxidant activity among heating temperatures and times (p<0.001), with heating temperature having the greater effect.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.433-440
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• 2016

Purpose: To provide the nutritional information of sweet peppers, we have evaluated changes of nutrient content and retention rates by different sweet pepper types and blanching method. Methods: Four types of raw and blanched ($100^{\circ}C$, 30 sec) sweet peppers were prepared and their weight, nutrient content (3 water soluble vitamins, 10 minerals) and retention rates were analyzed. Results: The weight of blanched sweet peppers was decreased than that of raw sweet peppers. From the results of the two-way analysis, the type of sweet pepper had a greater influence than blanching method used on the thiamine, riboflavin, folate and vitamin C contents (but not niacin) (p<0.05). Red pimento contained the most thiamine (0.1 mg/100 g), riboflavin (0.16 mg/100 g), folate ($47.89{\mu}g/100g$) and total niacin (0.11 mg/100 g). Red paprika contained high levels of riboflavin (0.15 mg/100 g) and folate ($44.96{\mu}g/100g$). Orange paprika contained the highest vitamin C content (116.29 mg/100 g). In addition, the mineral content, with the exception of Se, was strongly influenced by the type of sweet pepper rather than the blanching method (p<0.001). The K content of sweet peppers was higher than other minerals. Overall, after blanching, high retention rates (over 70%) were observed in all types of sweet peppers. However, the retention rates of thiamin, vitamin C and Se showed lower levels (less than 70%). Conclusion: The vitamin and mineral contents depends more on the type of sweet pepper; although vitamin and mineral (except Se) contents showed some changes after blanching. Our results can be utilized to determine the effects of cooking processes on nutritional information.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1047-1052
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• 2001

The pigment content in meju fermented by a Monascus species with different materials was studied. The relations between growth of M. pilosus and pigment production were positive and the correlation coefficient associated with this relationship was determined to be : r = 0.9879. Pigments produced by M. purpureus and M. pilosus were composed of 9 and 8 bands, respectively. One kind of them was yellowish, whereas the others were reddish. Total pigment levels in rice meju fermented by M. purpureus and M. pilosus were 335.25 and 1428.90$\mu\textrm{g}$/g, respectively. Pigment levels in the mejus fermented at 3$0^{\circ}C$ showed higher than those at 20 and 4$0^{\circ}C$. The order of pigment content in meju was polished rice > germinated brown rice > wheat > brown rice > waxy brown rice > germinated waxy brown rice. Pigment production by M. pilosus was higher than that of M. purpureus. Pigment content in rice meju prepared by adding 10% seed culture was highest, and pigment content of granulated rice was higher than that of powdered rice. Pigment production was not desirable in soybean meju fermented by seed culture, whereas the pigment levels in meju by adding 10% powdered rice and 10% powdered rice seed meju increased by 23.0 ~75.0 $\mu\textrm{g}$/g.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.166-170
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• 2008

The effects of heat treatments on the antioxidant activities of selected fruits and vegetables were investigated by heating at various temperatures (110, 120, 130, 140, and 150$^{\circ}C$) for 2 hr. The examined fruits and vegetables included tomatoes (Lycopersicon esculentum), oriental melon (Cucumis melon var. makuwa), apples (Malus pumila Miller var. domestica Schneider), melon (Cucumis melon), watermelon (Citrullus vulgaris), and banana (Musa sapientum). The total polyphenol and total flavonoid contents of the juices from heated samples were quantified spectrophotometrically, and their antioxidant activities were determined using DPPH and ABTS radicals. As the heating temperature increased, antioxidant activity also increased. The highest total polyphenol content (2.80 mg/g) occurred in the oriental melon with heating at 150$^{\circ}C$, and this value was 7 times higher than that of the untreated oriental melon (0.40 mg/g). The highest total flavonoid content (148.80 ${\mu}$g/g) occurred in the melon heat treated at 150$^{\circ}C$, and this value was 37 times higher than that of the untreated melon (4.54 ${\mu}$g/g). DPPH radical-scavenging activity was the highest in the watermelon treated at 150$^{\circ}C$ (84.37%, 0.50 mg/g), and this value was 40 times higher than that of the untreated watermelon. Finally, the highest ascorbic acid (AA) equivalent antioxidant capacity (AEAC) value (239.50 mg AA eq/g) was obtained in the watermelon heat treated at 150$^{\circ}C$ for 2 hr (control = 18.35 mg AA eq/g).

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.810-816
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• 1996

This study was conducted to measure the hydration characteristics at $20^{\circ}C$ and investigated the effect of water to rice ratio(v/w) on the texture properties of cooked rice of ten different varieties based on maturity. Water absorptions during soaking were completed between 30min and 35min at $20^{\circ}C$. The ranges of equilibrium moisture content were between 0.3247g $H_2O/g$ dry matter and 0.3577g H201g dry matter. During the cooking process, the water content of cooked rice increased 6~7% with increased the ratio of water to rice from 1.4 to 1.6(v/w). The hardness(H) of cooked rice decreased, while the stickiness(-H) and -H/H ratio increased with increased ratio of water to rice.