• Journal of Ginseng Research
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• v.29 no.2
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• pp.113-118
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• 2005

This study was to examine the effect of the opening ratio (area of spile hole/total surface area) of plastic container and storage temperature on physicochemical changes of fresh ginseng. At room temperature ($19\~23^{\circ}C$, RH $40\~61\%$), fungi and spoilage were observed 4 and 10 days, respectively after storing the fresh ginseng in a closed container. In storage container with $1\%$ opening ratio, fungi appeared 8 days after storage. In the container with $5\%$ and $10\%$ opening ratio, fresh ginseng showed excessive loss of moisture on the surface only after 4 days. The weight loss was most remarkable in the container with 5 and $10\%$ opening ratio. Content of maltose and sucrose decreased gradually in accordance with storage time but the extent of decreasing ratio was less significant in the container with lower opening ratio. At low temperature $(4\~9^{\circ}C,\;RH\;72\~92\%)$, no fungi but $10\%$ loss of weight was observed in the container with $5\%$ and $10\%$ opening ratio after 12 days storage. But in the tightly closed container and $1\%$ opening ratio for spiting, fresh ginseng showed good appearance even after 30 days of storage. Free sugars, especially maltose revealed gradual decrease but sucrose gradually increase following decrease at the beginning. This result suggests that storage condition of low temperature and opening ratio of plastic box less than $1\%$ can extend storage span of fresh ginseng significantly.

• Food Science and Preservation
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• v.23 no.3
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• pp.301-309
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• 2016

The objective of this study was to investigate physicochemical and antioxidant characteristics of immature flat persimmon during 7 heat treatment aging steps. The pH decreased, and hence, acidity increased with aging. Hunter L value decreased with aging. The a value rapidly increased until step 3, whereas the b value decreased. Fructose content decreased while glucose contents slightly increased during aging. Hardness, chewiness and gumminess rapidly decreased, indicating softening in texture, but it was negligible after aging step 3. Phenolic compounds including gallic acid and homogentisic acid were detected at step 3 and then gradually increased with aging. However, contents of flavonoid and tannin were much higher in step 1 sample than others. The antioxidant activities observed by DPPH, ABTS, and FRAP assay were the highest at step 1 possibly due to the higher levels of flavonoids and tannin acid in the step 1 sample.

• Food Science and Preservation
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• v.18 no.2
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• pp.171-177
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• 2011

In order to demonstrate the usefulness of Deodeok. the functions of Deodeok and the qualities of Cheongkukjang were investigated. DPPH (1.1-diphenyl-2-picryl-hydrazyl) radical scavenging activity of Deodeok extracted with 70% ethanol was higher than that of water extract. The direct antimutagenic effect of ethanol extract of Deodeok was examined by Ames test using Salmonella typimurium TA 98. The inhibition rates on ethanol extract at concentrations of 200, 1.000, 2.000, 3.000 and 4.000 ${\mu}g$/plate were 5.75, 31.38, 34.75, 53.50 and 83.75%, respectively. The inhibition rates of ethanol extract was higher over 2 times than that of water extract. The qualities including physicochemical and sensory properties of Deodeok Cheongkukjang were investigated over the following range of Deodeok levels; 5, 10, 15 and 20% (w/w). The strain used in Cheongkukjang manufacture was Bacillus sp. B-3 with the highest enzyme activities such as amylase and protease. During fermentation at $40^{\circ}C$ for 6 days. amino-type nitrogen content of Cheongkukjang containing 10% (w/w) Deodeok was more than others. When Deodeok content exceeded 15% (w/w), higher contents resulted in lesser amino-type nitrogen production. The results showed that Deodeok had influenced the growth of Bacillus sp. B-3. The L-value of Deodeok Cheongkukjang was decreased according to increasing the Deodeok contents. Sensory evaluation showed that Deodeok Cheongkukjang containing 10% (w/w) Deodeok was superior to other tested.

• Food Science and Preservation
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• v.16 no.3
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• pp.355-361
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• 2009

In this study, raw ginseng produced by different methods was puffed, and physicochemical properties were analyzed and compared. Raw ginseng included white ginseng lateral root (WGL), red ginseng lateral root (RGL), red ginseng main root (RGM), and red ginseng main root with 15% (w/w) moisture (RGMM). All samples were puffed at a pressure of 7 kg/cm2. Crude saponin content was increased after puffing compared with that of control ginseng. RGM and RGMM showed significant increases in crude saponin content, from 1.67% and 1.41% to 2.84% and 3.09% (all w/w), respectively. However, the ginsenoside content of WGL was decreased after puffing. Rg3, Rh1, and Rh2 values of red ginseng were increased by puffing compared with those of control red ginseng. The total sugar content of ginseng decreased after puffing. The mineral components of puffed ginseng were similar to those of raw ginseng. Levels of total phenolic compounds and antioxidant activities of ginseng were increased after puffing, and electron-donating ability was greatly increased. The acidic polysaccharide content of ginseng increased slightly and the amino acid content decreased due to the high temperature used during puffing.

• Food Science and Preservation
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• v.17 no.2
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• pp.174-181
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• 2010

The yeast strains used for fermentation are known to influence the qualities of wine. We investigated the effects of fermentation using different yeast strains on the properties of wine produced from 'Hayward' kiwifruit (Actinidia deliciosa). The physicochemical characteristics of wine produced using various yeast strains for fermentation were also analyzed. Saccharomyces cerevisiae Gervin No.5 strain (GVN), S. bayanus Lavin strain EC1118 (EC1118), and S. cerevisiae Red star Davis No. 796 (No.796) are commercial dry yeast strains selected for optimization of fermentation. Although the soluble solid contents of samples fermented by all three yeast strains decreased by a similar extent, the levels of alcohol production differed, particularly during the first week of fermentation. Use of the GVN strain resulted in the highest alcohol concentration (13.8%, v/v), whereas fermentation with No.796 and EC1118 strains yielded alcohol contents of 13.0% and 12.5% (both v/v), respectively. Upon sensory evaluation, GVN-fermented wine had a strong taste and bitterness, with high acid and alcohol contents. Wine fermented using No.796 had a chemical profile similar to that of GVN-fermented product, but the taste remained sweet, consistent with the lower alcohol content. EC1118-fermented wine was soft and sweet in taste, high in flavor, and had a low alcohol content. Total phenolic levels and antioxidant activities in wine fermented by EC1118 were significantly higher than in wines prepared using No.796 or GVN. When previously described characteristics were additionally considered, EC1118 was selected as an optimum strain for further study. In conclusion, fermentation of kiwifruit using different yeast strains yielded wines with distinct characteristics. The yeast strain EC1118 had the most desirable properties, and is considered suitable for kiwifruit fermentation. Valuable attributes of wine fermented by this yeast include overall sensory acceptance, an appropriate level of total phenolics, and good antioxidant activity.

• Food Science and Preservation
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• v.17 no.2
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• pp.230-235
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• 2010

We investigated the physicochemical quality characteristics of apple juice upon sterilization using hot water, and under various storage conditions. None of sugar content, acidity, or pH differed significantly among various sterilization conditions but chromaticity was considerably reduced in sterilized juice compared with control material. The chromaticity of non-sterilized juice decreased significantly after sterilization compared with material supplemented with vitamin C (0.1%, w/v). Fungi, yeast, and aerobic bacteria were detected in juice sterilized at $65^{\circ}C$ for 10 or 20 min, but no microorganisms were observed in juice sterilized by other procedures. Vitamin C content affected sterilization temperature to a greater extent than sterilization time. When juice was stored at $4^{\circ}C$ or $37^{\circ}C$ for 3 weeks after application of different sterilization conditions, almost no change in acidity, sugar content, or pH was observed, regardless of sterilization mode or storage period. However, chromaticity decreased with longer storage. Vitamin C levels were reduced by higher sterilization temperatures. However, longer storage periods had the greatest effect on reduction of vitamin C levels, which tended toward lower values regardless of differences in sterilization and storage conditions. In sensory evaluation tests, all of taste, color, and overall preference were highest for juice sterilized at $75^{\circ}C$ for 20 min. The ASC value was low at a storage temperature of $4^{\circ}C$ and at high sterilization temperatures, and a long storage period was associated with a greater ASC value. Thus, the quality of apple juice was excellent when juice was hot water-sterilized, with additional vitamin C, at $75^{\circ}C$ for 20 min, followed by storage at $4^{\circ}C$.

• Food Science and Preservation
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• v.16 no.3
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• pp.362-370
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• 2009

Quality changes in semi-dried red pepper (SRP) treated with ozone water were observed upon storage (at $-18^{\circ}C$) after freezing at $-10^{\circ}C$, $-20^{\circ}C$, and $-40^{\circ}C$. Drip loss after treatment was greater than in control peppers, but no significant difference was evident between treatments (p<0.05). We observed that differences between samples decreased as storage time increased. Texture after treatment did not change significantly over a 3-month period. The redness (a-value) after treatment was greater than in the control, but no sample showed significant color alteration after the 3-month period. The capsaicinoid content decreasedas storage time increased, and was also affected by the freezing temperature. However, carotenoid content was not influenced by freezing or storage temperature. Ascorbic acid and free sugar contents showed decreases of 47% and 6.5%, respectively, after semi-drying. The results of sensory evaluation indicated no significant difference between samples in terms of color appearance.

• Membrane Journal
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• v.18 no.4
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• pp.282-293
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• 2008

Partially sulfonated poly(aryl ether sulfone) membranes were prepared from the sulfonated sulfone monomer, which was synthesized by a nucleophilic substitution, non-sulfonated monomers and potassium carbonate by a direct polymerization method and a subsequent solution casting technique with mixed solvents of N-methyl-2-pyrrolidone (NMP) and dimethylacetamide (DMAc). To investigate the effect of mixed solvent, the volume ratios of NMP and DMAc were varied in the range of $0{\sim}100%$ and the degrees of sulfonation of the copolymers were fixed as 50%. The surface properties of the resulting membranes were examined by scanning electron microscope (SEM) and atomic force microscope (AFM), and a comparative study of the morphology changes and the physicochemical properties such as proton conductivity and methanol permeability was achieved. It was found that proton conductivities depend on the volume ratio of NMP-DMAc mixed solvents, and the proton conductivity determined at the condition of $25^{\circ}C$ and 100% relative humidity was $1.38{\times}10^{-1}\;S/cm$ for the membrane prepared in the 50:50 v/v-% of NMP : DMAc mixed solvent.

• Culinary science and hospitality research
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• v.16 no.5
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• pp.247-263
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• 2010

This study was conducted to examine the physicochemical and sensory characteristics of Bulgogi seasoning sauce added with Angelica gigas Nakai extract and salted liquid of Prunus mume. Increasing the amount of salted liquid of Prunus mume in the Bulgogi sauce added with Angelica gigas Nakai extract made its pH and brix decreased. And the lightness(L) value of the samples ranged from 22.50 to 23.43, and the redness(a) and yellowness(b) increased. For the textural characteristics of Bulgogi meat, the addition of salted liquid of Prunus mume decreased its hardness. In the sensory evaluation, Bulgogi added with 10% of salted liquid of Prunus mume made excellent scores in texture, taste and overall preference. Therefore, this results suggest that 10% of salted liquid of Prunus mume and Angelica gigas Nakai extract should be applied to Bulgogi sauce in order to satisfy its preference and functionality. For the changes of total viable cells of Bulgogi seasoning sauce by the storage period, increased amount of salted liquid of Prunus mume showed their number lower than that of the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.255-261
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• 2013

This study investigated changes in the physicochemical characteristics and coffee flavors of coffee beans under different roasting conditions. Four different kinds of roasted coffees were analyzed using a headspace gas chromatographic technique. The moisture content and total acidity of roasted coffee decreased whereas the pH and weight loss (%) increased, as coffee beans were roasted at higher temperatures. The Hunter's color values of the roasted coffee (indicating L (lightness) and b (yellowness)) decreased as the roasting temperature of the coffee beans increased, but a (redness) value only increased with light roasting. We also noted that the color of the Arabica coffee was darker than that of the Robusta coffee. The aroma compounds, acetaldehyde, acetone, 2-methylfuran, 2-methylbutanol, 2-methylpyrazine, furfural, 2-propanone, furfuryl alcohol, 2,5-dimethylpyrazine and furfuryl acetate were mainly analyzed. A sensory evaluation of all light-roasted coffees had flavor and sourness and those of all medium-roasted coffees had heaviness and finishness.