• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.242-256
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• 1997

The physico-chemical properties and possible biological functionalities of commercially available persimmon vinegars were studied by measuring the specific gravity, turbidity, color, pH, total acidity, reducing sugars, alcohols, total nitrogen content, composition of organic acids and amino acids, soluble pectin, soluble tannin, ascorbic acid, acetoinic compounds, electron donating ability and nitrite scavenging ability. Persimmon vinegars had low specific gravity(1.005-1.0200) and lightness(40.03-54.95), but high turbidity (0.12-1.311, absorptivity at 660 nm), redness(1.65--0.64) and yellowness(4.54-8.14) compared to the other fruit vinegars reported. These physical property values of the individiual product differed greatly. The tested persimmon vinegars contained relatively large amount of reducing sugars(0.45-0.84%, w/v), alcohol(0.16-3.18%, w/v) and total nitrogen(30-60mg%, w/v). The pH values (average 3.70) of products were relatively high and the total acidities(average 3.04%, w/v) of the tested persimmon vinegars were lower than that($TA{\geq}4.0%$) specified by the Korean standard for fruit vinegar. The major organic acids identified in the tested products were acetic acid(17.6-72.9%) and lactic acid(25.1-74.1%). The acetic acid contents in the 5 products out of the 7 tested persimmon vinegars were lower than lactic acid content. The level of free amino acids of the persimmon vinegars were relatively high in arginine, methionine and threonine. Persimmon vinegars contained relatively large amount of soluble pectin(91.8-232.8mg%, w/v), soluble tannin(49.0-161.7mg%, w/v) and ascorbic acid(12.8-29.6mg%, w/v). The persimmon vinegars were high in 2,3-butanediol (average 166.90ppm) and acetoin(average 111.43ppm). The persimmon vinegars showed strong electron donating ability and nitrite scavenging ability.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.60-71
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• 2014

This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.353-362
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• 2010

The contents of functional and nutritional components of 13 cultivars of Chinese cabbage (CC, $Brassica$ $rapa$ subspecies $campestris$) were analyzed to compare the effects of soil pH of the greenhouse (pH 6.2) and outdoor (pH 7.6). The CC cultivated on pH 6.2 (CC-6.2) soil contained significantly increased amounts (2-9 fold) of pectin, crude protein, vitamin C and vitamin E compared to the counterpart (CC-7.6). The contents of ash and the minerals (Ca, Fe, Na, and Mn) were also significantly increased in CC-6.2. However, CC-6.2 contained 40-50% lower contents of reducing sugars, cellulose and crude fat than CC-7.6. CC-7.6 contained more glucosinolates, gluconasturtiin (18.33 vs. $1.16nmol{\cdot}g^{-1}$ wet weight) and gluconapin (145 vs. $2nmol{\cdot}g^{-1}$ wet wt), than CC-6.2. In conclusion, CC-6.2 had an improved texture (high pectin and low cellulose) and nutritional value (high in protein, Ca, Fe, vitamin C, and E), whereas the CC-7.6 had better taste (high in reducing sugars) and anticancer functionality (high in glucosinolates).

• Journal of Mushroom
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• v.18 no.4
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• pp.357-364
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• 2020

The grade and price of Lentinula edodes largely differs in preference depending on the product area and seasonal factors. The product amount of autumn L. edodes was higher than that of spring L. edodes, but high quality, which is divided into "Hwago" is low in preference. Mostly, the autumn L. edodes is obtained as powder; hence, it is necessary to develop a processing method to utilize its flavor and aroma at an affordable price. Additionally, we estimated the content of 𝛽-glucan, ergosterol, vitamin D₂, reducing sugars, and free amino acids and evaluated the anti-inflammatory activity of saccharification powder of log-cultivated L. edodes. In the saccharification powders obtained via 7 min of UV irradiation of log-cultivated L. edodes, 𝛽-glucan and vitamin D₂ contents were found to be the highest, whereas ergosterol content was found to be the lowest. The content of reducing sugars ranged from 62.4 mg/L to 68.2 mg/L. The free amino acids were higher in these saccharification powders than in the control. Subsequently, RAW 264.7 cells were treated with different concentrations (10, 50, 100, 200, 300, and 500 ㎍/mL) of the saccharification powders of log-cultivated L. edodes obtained via different UV irradiation time applications. The cells showed good viability; the anti-inflammatory effect was found to be the highest at 7 min UV irradiation. Therefore, 7 min of UV irradiation was determined to be the optimum condition for manufacturing saccharification powders of log-cultivated L. edodes. Hence, saccharification powders of log-cultivated L. edodes may be used as a raw material for natural sweeteners, food additives, and in the food industry.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.88-91
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• 2001

Mixtures of rice and sweet persimmons to make sweet syrup, jochung, were saccharified by barley malt. Soluble solid contents, reducing sugar and free sugar contents, and sensory quality were determined in jochungs, which were prepared from various ratios (10 : 0, 7 : 3, 5 : 5, 3 : 7) of rice to sweet persimmons. Amylase activity had the highest value, 10466 Unit, after 3 hrs during saccharification process at $55^{\circ}C$. In HPLC determination of free sugars, maltose in saccharifying liquids found the highest amount followed by fructose and glucose. With increasing amounts of sweet persimmons, fructose and glucose contents increased while maltose content decreased. The soluble solid contents reduced as the sweet persimmons proportions increased. The control group without sweet persimmons showed highest value, $58^{\circ}Brix$, in soluble solid content. There appeared to be a slight decrease in reducing sugar and free sugar contents as proportion of sweet persimmons increased. Jochung prepared at high amounts of sweet persimmon had better scores in overall acceptance.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.153-160
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• 2011

In this study, we have developed taste and other functional enhancements of yam chips, from tasteless and flavorless yam slices, through the process of soaking freeze-dried yam in different commercially available juices, including apple, omija (fruit of Maximowiczia typica), grape, wild grape, orange, tomato, red ginseng, and black garlic juice. The analyses of color (brightness, redness and yellowness), pH, brix, acidity, total polyphenol, total flavonoids, total sugar and reducing sugar, DPPH and ABTS scavenging activity, reducing power and nitrite scavenging activity, of the different yam chips showed that the freeze-dried yam slices absorb various components of fruit juices, such as flavonoids, sugars, organic acids and flavors, during the soaking process. These changes resulted in increased taste (both sweet and sour tastes), flavor and antioxidant activity in the yam chips. The soaking time for yam slices in juice is considered to be a crucial factor for the taste and bioactivity of yam chips. In the case of grape juice-yam chips, which had the highest preference among the 8 different chips, the optimum soaking time was noted as 120 seconds. The optimization of the soaking process is necessary for various juices. These results suggest that taste, and other functional enhancements, in yam chips can be developed by juice-soaking and freeze-drying methods.

• Food Science and Preservation
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• v.21 no.3
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• pp.388-395
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• 2014

Six types of mixed cereals powder were prepared using different mixing ratios of barley, proso millet, sorghum, and adlay, and their nutritional components and functionalities were analyzed. The mixed cereals powders contained high levels of crude protein. The free amino acid and mineral contents of Sample E were the highest among all the samples. Fructose, glucose, sucrose, and maltose were detected as the four major free sugars in all the mixed cereals powders, and Sample D had the highest amount of reducing sugar among all the samples. The total polyphenol and total flavonoid contents of Sample F were significantly higher than those of the other samples. Sample C showed the highest level of DPPH radical scavenging activity and reducing power. As for the ABTS radical scavenging activity, the $IC_{50}$ of Sample D was the lowest among all the samples, but did not significantly differ from that of Sample C. Therefore, we suggest 2:2:1:1 (in Sample D) as the best mixing ratio of barley, proso millet, sorghum, and adlay to produce a mixed cereals powder with excellent nutritional value and antioxidant activities.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.598-606
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• 2004

The application of Dongchimi liquid to Naengmyon broth to improve its eating quality was scientifically explored by reviewing the quality of the product properties. Primarily, the optimum fermentation conditions for Dongchimi from which the liquid portion was extracted were pursued and the optimum mixing ratio sought on the basis of the product physicochemical properties. The liquid portions, periodically extracted from Dongchimi at intervals of two or five days, during fermentation at $10^{\circ}C$, were added to Naengmyon broth. The treatments were prepared at three levels namely, basic broth only ('A') and with ratios of Dongchimi liquid to basic broth of 3:7 (v/v, 'B') and 5:5 (vfv, 'C'). As a typical phenomenon of kimchi fermentation, a gradual decrease in the pH with increasing total acidity was observed as the fermentation of the Dongchimi progressed. At $10^{\circ}C$, the optimum ripening was obtained from day 8, and continued until day 15, when the pH was maintained at about 3.8 to 4.0. The total vitamin C and reducing sugar contents increased until the 13th-day of fermentation, but then decreased thereafter. The turbidity and solid content of the Dongchimi liquid increased with progression of the fermentation. With respect to the color values, the lightness (L) decreased, with increases in the redness (a), yellowness (b) and total color difference $({\Delta}E)$ during fermentation. Most of these observed phenomena for the Naengmyon broth substituted with $30\%$ (Treatment 'A') and $50\%$ (Treatment 'B') Dongchimi liquid, with different storage periods, confirmed the previous fermentation patterns of Dongchimi. A decrease in the pH with increasing total acidity, as well as gradual increases in the total vitamin C and reducing sugars (glucose and fructose) up to the 13th-day of fermentation were accompanied by subsequent declining patterns. The turbidity and solid content of the mixed broth also increased with increasing Dongchimi liquid fermentation period. With respect to the color of the mixed broth, the lightness was decreased, while the redness, yellowness and total color difference increased with increasing Dongchimi liquid fermentation period. It was also proven that the addition of slightly over-ripened Dongchimi liquid to the Naengmyon broth was more preferable.

• Journal of the Korean Dietetic Association
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• v.19 no.2
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• pp.112-123
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• 2013

HbA1c was recently adopted as a reliable indicator for screening diabetes. This study investigated the ability of nutrition consultation to prevent diabetes in overweight women (BMI 23 $kg/m^2$ or more) using HbA1c as an indicator. Twenty overweight and obese women (with $HbA1c{\geq}5.7$%) completed the 12-week nutritional study, with individual and personalized nutrition counseling performed every 2 weeks. The main study guidelines involved the following: 1) reducing the intake of high fat foods and alcohol, 2) consuming a large amount of vegetables, 3) reducing the intake of simple sugars and empty-calorie foods, and 4) increasing physical activity to ${\geq}30$ min/day. Anthropometric (height, weight, BMI, body muscle (kg), body fat (%), waist and hip circumference, blood pressure) and biochemical parameters (fasting blood sugar (FBS), HbA1c, lipid profiles, hs-CRP) were measured before and after the nutrition consultation. After 12 weeks, the HbA1c<5.7% group had significant decreases in BMI, WC, HC, WHR, HbA1c, hs-CRP and also dietary intake of energy (P<0.01), carbohydrates, lipids (P<0.01), proteins (P<0.01) and cholesterol was significantly decreased (P<0.05). In the HbA1c ${\geq}5.7$% group, HbA1c, TC, LDL, NON-HDL, hs-CRP and dietary intake of energy, carbohydrate, lipid, protein, and cholesterol significantly decreased (P<0.05). These results suggest that nutrition consultation effectively helps to prevent diabetes in overweight and obese women after applying HbA1c standards. Overall, the improvement in all markers measured suggest that HbA1c is a good indicator for blood glucose regulation, helping to prevent diabetes.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.226-230
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• 1994

In order to compare fall cultivars of Chinese cabbage for kimchi preparation, their physicochemical and organoleptic properties during kimchi fermentation were investigated. When physical characteristics of ten fall cabbage cultivars were compared, `Olympic' had the heaviest average weight and `Chungsan' was the longest in total length. They were also analyzed chemically and compared on water content, vitamin C and reducing sugars. `Noranmat' had the highest water content and `Chungsan' had the highest contents of vitamin C and reducing sugar. Kimchi samples prepared with each fall cultivar were fermented at $4^{\circ}C$ for $40^{\circ}C$ Says, of which pHs and total acid contents were measured and sensory characteristics were compared. Their pHs of `Lipdong' and `Taebok' were lowered most slowly and their pHs of all cultivars were lowered to less than pH 4.0 after the storage of 40 days. Their total acid contents of most cultivars were ranged from 0.55 to 0.59% after the same period. It was shown from the result of sensory eva uation that `Karaksin-1' and `Olympic' were considered to be the best among fall cultivars of Crinese cabbage for kimchi preparation.