• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.628-634
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• 2003

To investigate the effects of storage and pasteurization temperature on the quality of kiwi juice $(13.5^{\circ}Brix)$, the Kiwi juice was pasteurized at 65, 75 and $85^{\circ}C$ for 15 sec. The microbial, physicochemical measurements and sensory evaluations were conducted at the same condition during storage at 4 and $25^{\circ}C$ for 30 days. Most of the vegetative bacteria cells in kiwi juice were destroyed by heat treatment over $65^{\circ}C$, and they did not actively grow in kiwi juice after pasteurization. The D values of bacteria in kiwi juice by tubular type of heating exchange were 4.17, 1.47 and 0.81 sec at 65, 75 and $85^{\circ}C$, respectively. The growth of microorganisms during storage were not detected in the most samples. The amounts of vitamin C decreased as the pasteurization-storage-temperature and storage time increased. While reducing sugar increased as the pasteurization-storage temperature-storage time increased, it decreased rapidly after 20 days of storage. Hunter's color values L, a and b of stored kiwi juice were decreased at all storage conditions, browning reaction rate increased as the pasteurization-storage-temperature was decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.736-742
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• 2013

The physiochemical properties of commercial fruit vinegars were compared according to fermentation methods. Type A vinegars were synthesized through acetic acid fermentation while Type B vinegars were produced using both alcohol and acetic acid fermentation serially. There were differences from using these fermentation methods; Type A vinegars had a lower pH and slightly higher total acidity than Type B vinegars. The content of total sugar and reducing sugar were relatively higher in Type B vinegars, which showed a higher content of the free sugars (fructose, glucose, sucrose, and maltose). The intensity of brown color and Hunter's a and b values were also high in Type B vinegars. In contrast, the content of organic acids was higher in Type A vinegars, which were mainly composed of acetic, tartaric, malic, and succinic acid. We were also able to estimate the fruit juice content of vinegars through its content of organic acids. Type B vinegars contained a higher total phenolics and flavonoids content than Type A vinegars, and showed a higher DPPH radical scavenging activity.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.215-220
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• 2006

Response surface methodology was implemented to determine an optimal extraction condition in Phellinus linteus water extract. Extraction was performed on 10 experimental conditions including independent variables such as extraction time $(1{\sim}5\;hrs)$ and water volume over sample (sample : $H_2O$ = 1 : $40{\sim}200$, W/V), color browning, reducing and total sugar, that were based on the significant levels of 10% of central composition design. Color browning, reducing and total sugar contents were found to be more affected when the water volume was increased rather than extraction time. Maximum extraction condition was acquired at extraction time of $3.0{\sim}4.5\;hrs$ and water volume of $40{\sim}58.2\;ml$. Being extracted at the optimal extraction condition two of the free sugars, sucrose (0.126%) and glucose (0.012%), were detected. Total content of the free amino acids was found to be $503.26\;{\mu}g%$. Among them, essential amino acid contents were revealed as 5.4%. One major peak from gel permeation chromatography contained polysaccharide(s) with the molecular weights of 10 KDa.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.70-76
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• 2013

The aim of this research was to analyze makgeolli with nineteen kinds of rice and koji. Among 19 rice, 18 rice were domestic products and one rice was an import. For the properties of koji made with 19 kinds of rice, the acidity was over 5.0 and the saccharogenic power was more than 60SP. Makgeolli brewed with 19 kinds of rice and the koji of each rice were analyzed for alcohol contents, pH, total acidity and solid contents during fermentation. After fermentation, raw liquor's alcohol degree was set 6.0%, the pH ranged 3.47-3.76, the total acidity 0.27-0.44%, the solid contents and the reducing sugar were $2.7-4.6^{\circ}$Bx and 2.49-6.01 mg/mL. Organic acid was detected 5 kinds (oxalic, malic, lactic, acetic, succinic acid) and free sugars were found such as glucose, maltose and fructose. Hwayoung, Hopum and Sura were higher than the residue in 15 kinds of rice in the preference test.

• Food Science and Preservation
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• v.19 no.4
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• pp.604-610
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• 2012

The nutritional composition and in vitro anti-oxidant activities of blueberry (Vaccinium ashei) leaf extract were investigated to examine their physiological characteristics. Calcium was the most abundant mineral. The principal free sugars were glucose, sucrose, maltose, and fructose. The amino acids were mainly composed of glutamic acid and aspartic acid. The fatty acids consisted mainly of 40.94% saturated fatty acid and 54.35% unsaturated fatty acid. In addition, the 112.64 mg% of vitamin C was analyzed as a natural anti-oxidant. Based on the bioactivity-guided isolation principle, the resulting ethanolic extracts from the blueberry leaf were divided into several fractions of n-hexane, chloroform, ethyl acetate, and water. The ethyl acetate fraction showed the greatest total phenolic content. The total phenolics and flavonoid were 50.51 mg of GAE /g and 13.09 mg%, respectively. The ABTS-radical-scavenging activity of the ethyl acetate fraction was 97.53% at a concentration of 500 ${\mu}g/mL$. The ferric-reducing anti-oxidant power of the ethyl acetate fraction increased in a dose-dependent manner. The results suggest that the ethyl acetate fraction of the blueberry leaf extract has good in vitro anti-oxidant activities and excellent nourishment, and can thus be useful food resources.

• Food Science and Preservation
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• v.24 no.3
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• pp.406-412
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• 2017

In this study the physicochemical properties and antioxidant capacities of ginger (Zingiber officinale Rosc) Jungkwa with different kinds of sweeteners were determined. Jungkwa made with different sugars (sugar, xylitol, honey or oligosaccharides) were compared in aspect of physiochemical properties, antioxidant activities, total phenolic contents and sensory evaluation. Moisture contents Jungkwa treated different kinds of oligosaccarides showed highest value, in the order of honey, xylitol and sugar. $L^*$ value of Jungkwa treated with xylitol was the highest, $a^*$ value of Jungkwa treated with honey, sugar JungKwa were higher then others. Free sugar contents of Jungkwa treated with sugar showed the highest value in sucrose, glucose and galactose. Jungkwa with xylitol showed lowest value in all free sugar contents. Hardness and chewiness of Jungkwa treated with xylitol showed the highest value. The antioxidant activity measured by DPPH and ABTS radical scavenging activity and total penolic content were the highest in Jungkwa treated with honey, followed by Jungkwa treated with xylitol, oligosaccharides and sugar. Appearance and color of oligosaccarides and honey treated Jungkwa were preferred. In ginger taste, sweetness, chewiness were highest in sugar treated Jungkwa (not significant difference in treatments). As a result, honey treated Jungkwa has higher antioxidant activity and quality than other sugar treatments.

• Journal of Appropriate Technology
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• v.5 no.2
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• pp.91-96
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• 2019

Microalgae do not require much land and make a higher efficient oil production. However, it costs still much higher than other biodiesel resources, such as crops. Sugars charge 80% of culture media when microalgae are massively cultured in the fermenter. This study aims to develop a cost-efficient process for sugar production from Chinese cabbage byproducts. Pre-treatment with 0.25% H₂SO₄ was most effective when chopped cabbage was incubated 50℃/130 rpm for 24 hours. To hydrolyze cabbage cellulose, we used cellulases secreted from Trichoderma. harzianum. T. harzianum was cultured at 28℃/pH 7/130 rpm for five days. Optimal enzymatic activity of cellulase was obtained by incubating at 0.24 FPU/ml/45℃/pH 5/130 rpm for three days. In comparison to other agricultural waste, such as rice straw, green tea leaves, and palm residue, Chinese cabbage produced the highest sugar yield. We found the optimal conditions to produce sugar from Chinese cabbage byproducts as a carbon source to culture biodiesel-producing microalgae. The efficient process developed in this study helps microalgae as a sustainable alternative energy source by cost-down.

• Clean Technology
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• v.29 no.2
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• pp.109-117
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• 2023

The purpose of this study is to develop a method for separating antioxidants and sugars from grape skin extract. The extract was first mixed with a variety of organic solvents to investigate whether the separation was feasible. When employing acetone, ethanol, dimethylsulfoxide, or dimethylformamide, the organic solvent-extract combination formed a single phase. However, when benzene, ethyl acetate, or n-hexane was added to the extract, the mixture separated into an organic and an aqueous phase and the pigments remained in the aqueous phase. On the other hand, when polyethylene glycol-2,000 (PEG-2000) and sodium citrate were added to the extract, the mixture was separated into three layers, with the majority of the flavonoids migrating to the top layer and 53% of the extract's glucose migrating to the bottom layer. The top layer had significant antioxidant activity, whereas the bottom layer showed no antioxidant activity. The glucose recovery in the bottom layer increased as the molecular weight of PEG increased and the highest recovery (67%) was observed when PEG-8,000 was added. The highest flavonoid separation was observed with PEG-2,000, followed by PEG-8,000 and PEG-400. The flavonoid separation when PEG-2,000 was added resulted in a flavonoid recovery of 48% and 0.2% from the top and bottom layers, respectively. Examining the effect of the separated solution using the agar disc diffusion method on yeast cell growth confirmed that the addition of the extract, the top, and the bottom layer did not inhibit cell growth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1082-1090
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• 2005

Jocheong was prepared by adding Lentinus edodes extract to improve its quality and to give some functional properties. Contents of crude protein, ash and crude lipid were similar to those of control, while carbohydrate content was decreased. Total mineral content were $1,916.03\~2,674.24mg/kg$ that was no difference between test samples. From HPLC determination of free sugars, Jocheong was found to contain maltose as the highest sugar, followed by glucose and fructose. In amino acid analysis, seventeen amino acid were identified and quantified. Glutamic acid in Jocheong was major amino acid. The major fatty acids in Jocheong $(0\%,\;control)$ were linoleic acid, palmitic acid, oleic acid, myristic acid and caproic acid. There was no significant differences in fatty acid composition, pH and reducing sugar content among the Jocheong samples. The viscosity and solid contents tended to decrease with the addition of Lentinus edodes extract. Increasing the ratio of mushroom extract in Jocheong tended to decrease the lightness, yellowness and redness in Hunter's color value. Although sensory value decreased with increasing Lentinus edodes extracts, use of mushroom extracts (7: 3; saccharification liquids: Lentinus edodes extracts) is recommended for making Jocheong.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.229-234
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• 2012

A key molecule in the pathogenesis of Alzheimer's disease (AD) is the ${\beta}$-amyloid peptide ($A{\beta}$) generated by ${\beta}$-secretase activity, an aspartic protease. This study was designed to evaluate inhibitory effect of the high-molecular weight water-soluble polysaccharides (Et-P) isolated and purified from Phellinus linteus fruiting body on ${\beta}$-secretase activity. The Et-P was purified from the hot water extract of Phellinus linteus fruiting body mainly by 75% ethanol precipitation and DEAE-Cellulose column chromatography. From the DEAE-Cellulose chromato-gram and molecular weight analysis, the Et-P was shown to be a mixture of three polysaccharides with molecular mass of 1,629, 1,294, and 21 kDa, respectively. The monosaccharide composition of Et-P was determined to be glu-cose, galactose, and mannose as major sugars, glucose being the most prominent one (48% in mole percentage). The elemental analysis and FT-IR analysis suggested that Et-P is typical polysaccharides having at least partially ${\beta}$-linkages and possible existing as complex with phenolic compounds. The laminarinase digestion and HPAEC-PAD analysis suggested that Et-P is a variant of beta-(1,3)-glucans. The Et-P showed DPPH radical scavenging activity and, especially, a significant inhibitory activity on ${\beta}$-secreatase activity (48% inhibitin at 100 ${\mu}g/mL$), suggesting that they may inhibit the formation of $A{\beta}$ which is the major causative of Alzheimer's disease. The results of this study suggest that the water soluble polysaccharides of Phellinus linteus fruiting body can be a potent material for the development of preventive or therapeutic agents for AD.