• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1004-1010
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• 2015

This study was conducted to investigate the changes in the physicochemical characteristics and antioxidant activity of cheonggukjang with the addition of walnuts. The pH of cheonggukjang did not change significantly with the addition of walnut. But the water content decreased significantly. Walnut addition to the soybean was expected to have a positive effect because the number of Bacillus subtilis was not reduced. The viscous substance content was significantly decreased when more than 20% of walnut was added to cheonggukjang. The addition of walnut made the color darker. The flavonoid and polyphenol content was sharply increased in proportion to the walnut addition and the DPPH radical scavenging activity of cheonggukjang also increased. Altogether, it was found that the addition of walnut had a positive influence on the cheonggukjang by increasing the antioxidant activity.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.383-389
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• 2016

Purpose: This study was conducted to evaluate the effect of rehydration and subsequent heating at high temperature on the pigments and antioxidants of dried samnamul (Aruncus dioicus) and daraesoon (Actinidia arguta). Methods: Rehydration included 16 h-soaking in cold water, and 30 min-boiling and 1 h-infusion in water. Rehydrated samnamul and daraesoon were heated at $180^{\circ}C$ for 10 or 20 min with or without perilla oil addition (10%) for cooking. Pigments and antioxidants were determined by HPLC and spectrophotometry. Results: Rehydration caused decreases in pigment and polyphenol contents, but increase in tocopherol content. Cooking by heating without addition of perilla oil resulted in increases in chlorophyll and carotenoid contents, but decreases in polyphenol and tocopherol contents. Decrease in tocopherol content by heating at $180^{\circ}C$ was reversed by the addition of perilla oil. Conclusion: This study strongly suggested that cooking of samnamul and daraesoon at $180^{\circ}C$ with perilla oil could improve color, texture, and potential health functionality by recovering the loss of antioxidants and pigments with antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.452-458
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• 2019

The objective of this study was to investigate the physicochemical characteristics and antioxidant potential of garlic processed using different heat treatments conditions, which is an effective method for removing the unpleasant odor and taste of raw garlic. The pH and soluble solid content of raw garlic (pH 6.07, $7.7^{\circ}Bx$) were almost equal or slightly higher than that of processed garlic samples (pH 5.06-6.09, $7.1-7.4^{\circ}Bx$). The color of processed garlic was also significantly affected. The amounts of amino acids such as ${\gamma}$-amino-n-butyric acid and few essential amino acids also increased after the thermal treatment of garlic. The antioxidant potentials of red and black garlic were higher than that of raw garlic. The polyphenol content of processed garlic ($38.51-81.51{\mu}g$ gallic acid equivalent/g sample) was significantly higher than that of raw garlic ($30.66{\mu}g$ gallic acid equivalent/g sample). These results indicated that heat treatment for different durations under a controlled environment enhanced the nutritional and functional properties of garlic.

• Journal of the Korean Society of Food Culture
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• v.38 no.6
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• pp.425-433
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• 2023

We determined physicochemical characteristics and antioxidant activities of cookies prepared by replacing wheat flour with 0, 3, 6, and 9% freeze-dried burdock powder instead of wheat flour. The leavening and loss rates of the cookies decreased in proportion to the amount of burdock powder added to the dough. The moisture content of the cookies increased in proportion to the amount of burdock powder added and the crude protein and hardness were higher in the burdock-added group compared to the control. The lightness and yellowness of the cookies decreased, and the redness increased in proportion to the amount of burdock powder added. The total flavonoid and polyphenol compounds in the cookies increased in proportion to the amounts of burdock powder added. The antioxidant activities also tended to increase in proportion to the amount of burdock powder added. Based on the above results, adding burdock powder to cookies can increase antioxidant activity by increasing the content of antioxidant components, such as polyphenols and flavonoids. In addition, it is believed that adding burdock powder at levels of 3 to 9% of the weight of flour would result in cookies with spreadability, swelling power, and hardness similar to those of regular cookies.

• Journal of Mushroom
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• v.15 no.4
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• pp.206-209
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• 2017

In this study, the morphology and antioxidant content of shiitake mushrooms (Lentinula edodes) cultivated in smart farms and general farms have been compared. With regard to morphology, mushrooms produced in the smart farm system exhibited a slightly thicker and wider pileus and thicker and longer stipe than those in the general farm system. The stipe in the mushrooms from moderate-sized farms was harder, because the low relative humidity of cultivation rooms could induce mushroom tissue to harden. With regard to the antioxidant content, the free radical scavenging activity was evaluated by the DPPH assay. Among the various treatments, hot water extracts of freeze-dried shiitake produced from smart farms exhibited the highest DPPH value of 37.8%. In contrast, the lowest activity of 12.2% was observed in a 70% fermented alcohol extract of shiitake that was dried by hot air. The polyphenol content was higher in hot water extracts than in 70% fermented alcohol extracts. Additionally, the polyphenol content was higher in the freeze-dried samples than in hot-air dried ones. The smart-farm system was preferred over the general cropping system for cultivating shiitake mushrooms, because the antioxidant activity and polyphenol content of mushrooms from the smart-farm system was better; the functionality of this system was more improved than that of the general cropping system, and it enables mushrooms to be cultivated more efficiently. The antioxidant content is represented as the $mean{\pm}SD$ of three replicates. Different letters indicate significant differences among samples, i.e., p<0.05.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.689-695
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• 2007

Antioxidative activity and polyphenol contents of heated licorice in Korea extracted by ethyl.acetate (EtOAc) and ethyl.alcohol (EtOH) were evaluated at various heating temperatures (110, 120, 130, 140, and $150^{\circ}C$), times (1, 2, 3, 4, and 5 hr), and moisture contents (10, 20, 30, 40, and 50%). Maximum extraction yields of EtOAc extract was 10.9% at $130^{\circ}C$, 3 hr, and 50% moisture content and that of EtOH extract was 25.0% at $120^{\circ}C$, 2 hr, and 20% moisture content, whereas those of control were 0.8 and 15.8%, respectively. The highest total polyphenol content was 845.67 mg/100 g in EtOH extract at $120^{\circ}C$, 2 hr, and 20% moisture content (control: 277.00 mg/100 g). The antioxidative activity ($IC_{50}$) was the highest value of 0.53 mg/mL in EtOAc extract at $120^{\circ}C$, 2 hr, and 20% moisture content (control: 12.34 mg/mL). The highest ascorbic acid equivalent antioxidant activity value of 1,584 mg ascorbic acid (AA) eq was obtained from EtOAc extract at $120^{\circ}C$, 2hr, and 40% moisture content (control: 1,263 mg AA eq). Optimum heating conditions for the improvement of antioxidative activity of licorice in Korea was $120^{\circ}C$, 2 hr, and $20{\sim}40%$ moisture content.

• Korean Journal of Plant Resources
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• v.36 no.1
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• pp.1-14
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• 2023

This study measured the antioxidant activity and phytochemical content of 192 Boehmeria nivea var. tenacissima (Gaudich.) Miq. collected from six regions in order to identify the possibility of its industrial application. Two antioxidant activity assay (DPPH radical scavenging activity and ABTS radical scavenging activity) and two phytochemical content assay (total polyphenol content (TPC) and total flavonoid content (TFC)) of 192 samples were analyzed. The results showed that the DPPH radical scavenging activity of 192 samples was ranged from 0.02 to 1.35 mgAAE/g, and among them, the samples collected from Goheung (0.53 ± 0.37) and Ulleungdo (0.52 ± 0.28) showed the highest activity. The ABTS radical scavenging activity was showed the ranged from 0.07 to 1.81 mgAAE/g, and the samples collected at Ulleungdo (0.47 ± 0.36) showed the highest activity. The total polyphenol content of 192 samples was 18.6 to 234.8 ugGAE/g, and the samples collected at Mokpo (93.4 ± 34.7) and Jindo (90.4 ± 24.5) showed the highest content. The total flavonoid content was 0.10 to 1.22 mgQE/g and the samples collected at Ulleungdo (0.49 ± 0.31) showed the highest content. In the correlation analysis, there was no significant relationship between the environmental conditions and the antioxidant activity. The total polyphenol content showed a positive correlation with daily temperature difference, and negative correlation with average wind speed and average humidity, and total flavonoid content showed negative correlations with the average temperature, maximum temperature, and minimum temperature. This result can be used as a basic data establish the cultivation conditions of B. nivea var. tenacissima (Gaudich.) Miq. as a functional raw material to increase the usefulness of B. nivea var. tenacissima (Gaudich.) Miq..

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.696-702
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• 2018

This study investigated the quality characteristics of jujube wines produced from various fruits (Campbell Early, aronia, apply). Before the preparation of jujube wine, jujube juice was extracted using hot water ($100^{\circ}C$, 2 hr). Different blends of jujube wines were produced by blending jujube juice with various fruits using Saccharomyces cerevisiae. After 18 days of fermentation, the alcohol content of jujube wines ranged between 11.5~12.7%. The pH of the wine ranged from 3.31 to 3.53 and the total acid content from 0.47 to 0.68%. The hue value of jujube wines ranged from 0.88 to 2.21 and the color intensity ranged from 0.93 to 6.29. The brightness of jujube wines ranged from 32.35 to 92.47, the redness from 0.85 to 59.05, and the yellowness from 17.35 to 51.02. By combining aronia with jujube juice, a significant increase in the total polyphenol content and the antioxidant activity (the DPPH radical scavenging activity) of the wine was observed. The total polyphenol content (401.77 mg%) and the antioxidant activity (76.29%) were the highest in the jujube wine blended with aronia. The total anthocyanin content of jujube wines ranged from 81.66 to 135.98 mg% and the tannic acid content from 42.48 to 316.36 mg%. Based on the results of the present study, we suggest that jujube wine produced by blending jujube juice with aronia had excellent quality as well as quality characteristics of the wine.

• Korean journal of food and cookery science
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• v.32 no.1
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• pp.16-26
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• 2016

In this study, we aimed to develop functional vinegar with different levels of black garlic through two stages of fermentation. Black garlic vinegars were prepared from black garlic and water (w/w) mixed with 1:2 (BG3), 1:5 (BG6), 1:9 (BG9) and 1:11 (BG12), and adding the sugar by adjusting the soluble solids content to $14^{\circ}Brix$. The alcohol content of black garlic vinegar was 5.2-5.5% after 7 days of alcohol fermentation at $25^{\circ}C$. Acetic acid fermented was at $30^{\circ}C$ for 25 days and samples were taken at 3, 6, 9, 12, 15, 20 and 25 days. The pH of black garlic vinegar was not significantly different among the samples, but acidity was increased during fermentation. Total polyphenol contents showed irregular changes with the fermentation periods and were higher by black garlic content. At 25 days fermentation, total polyphenol contents were 18.96-56.56 mg/100 mL. Acetic acid content of black garlic vinegars was higher than other organic acids. S-allyl cysteine (SAC) contents of BG3 and BG6 were 13.03-14.54 and 1.69-2.20 mg/L, respectively. However SAC was not detected in BG9 and BG12. In 25 days fermented black garlic vinegar, the major mineral was K with a content ratio of 61-68% of total minerals. The DPPH and ABTS radical scavenging activity of 25 days fermented black garlic vinegar were stronger at higher black garlic content.

• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.299-308
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• 2020

This study investigated the quality characteristics of black soybean sediments to diversify the availability of soybean. The cooking method selected for black soybean sediment preparation was a pressure cooking process without soaking, considering the isoflavone content. The black soybean sediments were prepared by the addition of 0, 10, 30, 50 and 100% (w/w) black soybean. When 0% to 100% black soybean was added to the black soybean sediments, the moisture and crude protein contents increased from 53.17% to 54.41% and from 12.07% to 21.68%, respectively. The total isoflavone content of the black soybean sediments was increased from 2.69 ㎍/g to 696.09 ㎍/g, respectively, by the addition of black soybean. The anthocyanin content of the black soybean sediments ranged from 279.29 ㎍/g to 387.8 ㎍/g by the addition of black soybean. The total polyphenol content and the total flavonoid content of the black soybean sediments range from 1.72 mg/g to 2.00 mg/g and 0.89 mg/g to 0.92 mg/g, respectively, by the addition of black soybean. Given the isoflavones, total polyphenol, and anthocyanin content of the black soybean sediments, it is appropriate that the ratio of added black soybeans is at least 50% after the pressure-cooking process, regardless of soaking.