• Food Science and Preservation
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• v.12 no.6
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• pp.529-533
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• 2005

The respiratory characteristics of Korean fresh ginseng were investigated from the aspect of picking season, size, and storage temperature and period to get basic data for extension of shelf-life. The respiration rate of fresh ginseng picked in March was 4.09 mL $CO_2/kg{\cdot}hr$ at $0^{\circ}C$. It was gradually increased to August, 7.88 mL $CO_2/kg{\cdot}hr$ at $0^{\circ}C$, and then decreased continuously until November. Although the rate of fresh ginseng was different by picking season, the respiration quotient showed the same level, $1.03\~1.07$. Respiration rate by size was ranged from 3.47 to 5.69 mL $CO_2/kg{\cdot}hr$ at $0^{\circ}C$, and smaller in the size was higher in the rate. $Q_{10}$ value of fresh ginseng was $2.68\~2.88$ when the temperature increased from $0^{\circ}C\;to\;10^{\circ}C$ and $1.77\~2.16$ from $10^{\circ}C\;to\;20^{\circ}C$, and it was slightly different by picking season. At the beginning of storage the respiration rate was 7.0 mL $CO_2/kg{\cdot}hr$ and it was .decreased to 3.38 mL $CO_2/kg{\cdot}hr$ after storage for 90 days at $0^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.934-941
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• 2008

Effect of electron beam irradiation (1 and 2 kGy) on apricot was determined in order to develop preservation techniques to enhance shelf-life during 2 weeks at room temperature. Aerobic bacteria and molds/yeasts in apricot were reduced significantly with the increase of irradiation dose. Hardness of apricots decreased during storage by irradiation. Hunter's color value results showed that lightness and redness of irradiated samples were low compared with control samples. Also, sensory test resulting overall acceptability was not significantly different by 1 kGy irradiation during the storage days. Reducing sugar contents was increased gradually, and value of irradiated samples was high compared with non-irradiated sample. Organic acid contents of 2 kGy irradiated samples was not significantly changed during storage. In pH, total sugar, hydrogen donating activity and vitamin C contents, there were no significant differences between treatments. The electron beam treatment on apricots at 1 and 2 kGy did not affect pH, total sugar, hydrogen donating activity and vitamin C contents but improved microbial safety.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.108-114
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• 2016

The effects of $SO_2$ treated pads ($SO_2$ 0, 0.5, 1, and 2 g/kg) on the quality of dried persimmons slices were investigated. The $SO_2$ treated pads for storage did not affect to weight, moisture loss rate, and soluble solid contents of dried persimmons slices. The color change after storage for 12 weeks was the highest (value = 3.5) in control ($SO_2$ 0 g/kg), whereas that was the lowest (value = 2.0) under $SO_2$ 2 g/kg condition. When we measured the browning degree after 12 weeks, they showed O.D. 0.24, 0.22, 0.20, and 1.7 in serial dilution treated pads with $SO_2$ 0, 0.5, 1, and 2 g/kg, respectively. The decaying rate was the highest (7.0%) in control after 12 weeks storage, whereas it did not show any spoilage in $SO_2$ 1 g/kg and 2 g/kg treated condition for whole storage period. The concentration of residual $SO_2$ in dried persimmons slices was detected within a safe range of 20.3~40.3 ppm. Therefore, the shelf-life of dried persimmons slices was lengthened in $SO_2$ treated pads (especially in $SO_2$ 2 g/kg) for inhibiting of browning and decaying.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.148-152
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• 2013

An ultraviolet (UV) sterilization system was developed to decrease the number of microorganisms in filtered Acer mono sap (FAS). The Acer mono sap (AS) was passed through 18 strips of PTA fluoroplastic tubing with 30 UV lamps (total 1,170 W). During passage, the AS was effectively exposed to the UV rays. The total bacteria, coliform group and fungi were sterilized at a flow rate ranging from 852 to 1,358 mL/min and a UV power higher than 156 W. Although the sensory score of the UV-sterilized AS was significantly lower than that of the untreated AS, the sensory score was better under the condition of 390 W and 852~1,358 mL/min than under the other conditions examined. ANOVA did not reveal a significant difference in pH, total acidity, sugar content and color characteristic under all conditions tested (p<0.05). Considering the overall attributes of the AS quality, the optimum sterilization condition was determined to be 390 W and 852~1,358 mL/min.

• Journal of Dairy Science and Biotechnology
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• v.14 no.1
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• pp.85-95
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• 1996

This study was conducted to obtain basic data about the effect of Lactobacillus delbruckii on the quality and preservability of the bread during bread making. The parameters measured to investigate the bread quality were water content, water activity, pH, hardness, shelf life and sensory evaluation. The results obtained were as follows : 1. During the storage period, moisture evaporated faster in normal bread than the sourdough bread(10, 30, 50%). 2. Normal bread showed 0.94 and sourdough bread resulted from 0.94 to 0.96 in water activity, 3. The concentration rate of sourdough and different dough method resulted in significantly difference value of pH in bread. As the sourdough concentration rate increased the pH changed from 5.5 to 4.5 in sponge dough method. However, the sourdough concentration rate increased, the pH dropped from 5.4 to 4.8 in the bread which made by straight dough method. 4. The normal bread showed tough texture than the sourdough bread as the storage period is extended. 5. As the ratio of sourdough increased, the pH became lower and the production of the off fiavor, the growth of mold delayed for one or two days when stored at 30$^{\circ}$C. 6. The bread with sourdough resulted in higher score than the normal bread by sensory evaluation. 7, The bread with 30% sourdough by straight dough method showed the highest score and the bread with 10% sour dough by sponge dough method resulted in the highest score by sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.98-104
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• 2011

The storage quality of fresh buckwheat sprouts, as influenced by pretreatment and packaging within processing steps, was investigated to establish appropriate postharvest handling treatment for the commodity. After harvest, the sprouts were dipped in chlorine water (100 ppm), rinsed twice with clean water, pre-cooled with iced water, de-watered, and packed in plastic trays. Sprout samples taken from each processing step were stored at $5^{\circ}C$ for 6 days to measure quality attributes. Viable cell counts of mesophilic aerobes and coliform bacteria were lower by about 1 log scale in the postharvest treated samples compared to an untreated control, although the initial microbial reduction due to the postharvest treatments was offset by cell growth during storage. All sprout samples showed a decrease of fresh weight by approximately 4% after 6 days of storage. However, moisture and soluble solid contents were maintained at the initial levels of the sprouts. No significant difference in surface color was observed among sample treatments. For sensory properties including discoloration, wilting, decay, and visual quality, there were no significant differences among sample treatments. The present results suggest that proper postharvest processing treatments can exert positive effects on extending the shelf-life of fresh buckwheat sprout.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.770-775
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• 1994

Kimchi packed in polypropylene(PP) tray was stored at different temperatures (0, 10, $20^{\circ}C$) to investigate the relationships between fermentative gas pressure and quality changes. The quality of Kimchi during storage was evaluated in terms of pH, titratable acidity, color, and sensory properties. The fermentative gas pressure changes due to $CO_2$ evolution showed typical sigmoidal curves at each temperature. Accordingly, inflation of Kimchi packages caused by increasing gas pressure occurred in 40 hours, 5 and 30 days at 20, 10, $0^{\circ}C$ , respectively, at which gas pressure inside the packages ranged $1.2{\sim}1.4\;psig$. Following inflation, Kimchi packages stored at 20 and $10^{\circ}C$ were burst out on 3 and 8 days, but those at $0^{\circ}C$ were not. As the fermentative gas pressure increased, pH decreased (r > 0.968) and titratable acidity increased (r > 0.973) proportionally. Regarding to the color change of crushed Kimchi juice, L and b values were decreased exponentially, but a value remained constant during storage. Among sensory properties, the sourness and texture scores showed good accordance with pH changes. In conclusion, although Kimchi kept optimal tastes during storage, the inflation of package restricted shelf-life of Kimchi.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.244-249
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• 1982

In order to reduce malic acid in low-alcohol content appel wine $(6{\sim}9%)$ malate-decomposing yeast, Schzosaccharomyces japonicus var. japonicus St-3 was used. Fallen apples before the harvesting season were collected and extraction was made. The apple extract was fortified with sucrose to make final sugar concentration of 18% in case of 9% base wine. High acid content in the primarily fermented apple wine could be reduced by following with malo-alcoholic fermentation using Schizosaccharomyces japonicus var. japonicus St-3 in second half of alcoholic fermentation using Saccharomyces sp. R-11. Secondary fermentation was proceeded at low temperature $(7{\sim}8^{\circ}C)$ for 130 days using Saccharomyces sp. R-11. Prior to the secondary fermentation, two percent of sugar was added to the base wine in order to produce carbon dioxide gas. And each five percent of specially prepared malt extract and hop extract were added to the base wine in order to increase foam stability. Better shelf-life was observed by keeping high carbon dioxide pressure$(2.3{\sim}2.5kg/cm^2)$ in the bottle. It was assured that the better low-alcohol content apple wine could be brewed by the method which we used above.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.421-425
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• 1990

This study was carried out to compare lactic acid bacteria count of liquid type yogurts with various experimental conditions during shelf-life period. The conditions were media(BCP and Elliker agar), incubation conditions(aerobic and anaerobic), dilution waters(saline and phosphate buffer) and dilution methods(10 and 100 times). All of the samples were incubated at $37^{\circ}C$ for 72 hrs. In the case of counting L. acidophilus as a yogurt starter culture, there were differences on dilution waters and incubation conditions, but were no difference on media and dilution methods. In the case of counting L jugurti and mixed strain with L. acidophilus and L. casei, there were differences on media, incubation conditions and dilution waters, but was no difference on dilution methods. For L. casei in the yogurt, media and dilution methods were shown slightly different viable cell count but incubation conditions were not shown difference. In the case of counting L. bulgaricus, there were differences on media, incubation conditions and dilution methods, but was no difference on dilution waters. Therefore, the measurment of lactic acid bacteria count may be effective if preferred experimental conditions are selected for different types of strain.

• Research in Plant Disease
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• v.10 no.4
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• pp.272-278
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• 2004

The disease development of Anthracnose of sweet persimmon in relation to release of conida of Colletotrichum gloeosporioides were observed in a farmer's field located in Jinju from 1998 to 2002. The conidia started to release from early April and reached maximum in June to late July. The amount of conidia production reduced drastically from early August. The number of conidia trapped was closely related to amount of precipitation at the same period and number of new infections on the emerging branches and young fruits in orchard. The conidia released during the April was not effected to disease occurrence of persimmon tree but the spores produced from inoculum source after early May significantly important to the infection of the pathogen on emerging branch and this infection was directly related to infections on young fruits. Consequently the early infections on the branches brought severe occurrence of Anthracnose in the orchard. Most of the infected fruits were dropped in unripe state. The earlier infection caused the earlier fruit drop. The rate of fruit drop was reached up to 84.1% in August when the disease was occurred severely. Anthracnose of sweet persimmon also occurred in market shelf and storage warehouse. The anthracnose fruits are presumed to be infected while in orchard. Because the symptom formed on the fruit was too tiny to eliminate, the infected fruits were involved in storage boxes and anthracnose gradually developed in storage condition. The rate of diseased fruit observed in Jinju area were 1.2 to 1.6%.