• Food Science and Preservation
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• v.15 no.2
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• pp.225-230
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• 2008

We investigated the effect of modified atmosphere packaging (MAP) on the removal of astringency and overall quality of astringent persimmons (Diospyros kaki T. cv. Miryangbansi). Persimmons were packaged in 0.08, 0.10, or 0.12 mm low-density polyethylene film and then stored at $0^{\circ}C$ for up to 100 days. Concentrations of $O_2$ and $CO_2$ in the packaging maintained lower and higher as the film thickness increased Weight loss was strongly retarded by all three MAP films. Soluble tannin content decreased as the film thickness increased. The astringency of persimmons disappeared after 60-70 days in 0.12 mm film, after 80 days in 0.10 mm film, but did not disappear after 100 days in 0.08 mm film Loss of flesh firmness and decline in external appearance were slower in persimmons in 0.08 and 0.10 mm films than in those in 0.12 mm film. Our results show that 0.10 mm LDPE films can be effective for maintaining the quality and removal of the astringency of astringent persimmons.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1369-1374
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• 2008

This study investigated proximate compositions and quality characteristics of wet noodles with the addition of freeze dried garlic powders prepared at 0.5, 1.0, 2.0, and 4.0% based on flour source, respectively. The moisture, crude protein, crude fat, nitrogen free extract, crude fiber, and crude ash of the freeze dried garlic powder were $4.72{\pm}0.14%,\;19.46{\pm}0.28%,\;1.21{\pm}0.10%,\;68.45{\pm}2.06%,\;2.38{\pm}0.05%,\;and\;3.78{\pm}0.06%$, respectively. The cooked weight, volume, water absorption of cooked noodles were decreased, but the turbidity of soup was increased with the addition of garlic powder. Increased of L (lightness), a (redness) and b (yellowness) values were caused as the amount of garlic powder increased in dough. Decrease of L value and increase of a and b value were shown with the increase of garlic powder in cooked noodle. The cooked noodles with garlic powder were significantly lower in hardness, adhesiveness, springiness chewiness, gumminess and cohesiveness than those of 100% wheat noodle. Sensory evaluation indicated that cooked noodles with 0.5% garlic powder was not significantly different from the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.779-784
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• 2007

This study investigated quality characteristics of wet noodles with addition of paprika powder prepared by different cultivars, freeze dried Special paprika powder (FDSP) and freeze dried Fiesta paprika powder (FDFP) at 0.5, 1.0 and 2.0% based on flour source, respectively. The wet noodles containing paprika powder exhibited higher values for cooked weight, volume, water absorption, and turbidity. When the amount of FDSP increased, the Hunter L (lightness) value of cooked noodles decreased but a (redness) value and b (yellowness) value increased. When the amount of FDFP increased, the Hunter L (lightness) and a (redness) value of cooked noodles decreased but b (yellowness) value increased. From textural properties measured by a texture analyzer, the noodles with paprika powder were significantly lower in hardness, cohesiveness, springiness, gumminess and chewiness than those of 100% wheat noodle. The results of sensory evaluation of cooked noodles containing paprika powder indicated that the cooked noodles with 1.0% paprika powder showed the highest value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1072-1078
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• 2015

To maintain high quality and microbiological safety of paprika during storage for export, paprika samples after harvest were treated with 75 ppmv chlorine dioxide ($ClO_2$) gas and stored at $8^{\circ}C$, which is the optimal storage temperature, for 30 days. $ClO_2$ gas treatment reduced initial populations of total aerobic bacteria in samples by 1.62 log CFU/g as well as yeast and molds by 1.45 log CFU/g compared to those of the control. During storage, weight loss of all samples increased, and samples treated with $ClO_2$ gas showed lower weight loss than the control. In addition, total soluble solid and total phenolic contents were not significantly different between the samples during storage, whereas vitamin C content and hardness of all samples decreased. Hunter L, a, and b values of paprika samples were not significantly different between the treatments. These results suggest that $ClO_2$ gas treatment can be effective for improving microbiological safety and maintaining high quality of paprika during storage.

• Food Science and Preservation
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• v.22 no.1
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• pp.56-62
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• 2015

In this study, the quality characteristics of different drying methods of Aronia melanocarpa, which contains large amounts of bioactive substances, were investigated for the improvement of their practical use. During the drying period, the weight reduction was the highest with vacuum freeze drying (81.6%). The water content was reduced to the maximum level when vacuum freeze-drying was used. With regard to the color value measurement results, there were no significant differences in the $L^*$ value. Values of $a^*$ and $b^*$ were increased in vacuum freeze drying and cold air drying, but decreased in hot air drying. The hardness was increased dramatically after 36 hours of hot air drying, while with cold air drying, it increased slowly until 132 hr and increased rapidly after 132 hr. The dried yield was the highest with cold air drying (24.2%). As for the general component analysis results of Aronia melanocarpa, the moisture content was the lowest, and the crude protein and crude fat contents were the highest with vacuum freeze drying. No difference in pH value was shown among the dried Aronia melanocarpa obtained from the different drying methods, but the sugar content was the highest with vacuum freeze drying. The mineral content was the highest with cold air drying, and K, Ca, Mg, and Na were the major minerals. The free sugar content of dried Aronia melanocarpa was found to be 5.92~20.59 g/100 g, and the highest free sugar content was found with vaccum freeze drying.

• Food Science and Preservation
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• v.23 no.7
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• pp.913-922
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• 2016

The aim of this study was to develop a new salting condition that included added maltodextrin (MD) and grape seed extract (GSE) to ensure the microbiological safety and quality of salted shredded Korean cabbage. Response surface methodology (RSM) was used to analyze the effects of four independent variables (NaCl concentration, salting duration, MD concentration, and GSE concentration). The following response variables were evaluated: reduction in total aerobic bacteria, yeast, and mold counts; weight loss and salt content; and taste, texture, and overall acceptability of salted shredded Korean cabbage. The optimal salting conditions include a combination of 10.09~10.32% NaCl, 9.45~10.00% MD, and 234~300 ppm GSE in a ternary salting solution and a salting duration of 5.68~5.94 hr. This optimal combination reduced total aerobic bacterial and yeast/molds counts by 3.33 and 1.45 log CFU/g, respectively, while maintaining high sensory scores for taste, texture, and overall acceptability of the salted shredded Korean cabbage. In addition, the optimal conditions yielded more acceptable weight loss and salt content characteristics. The results suggest that use of the optimized combination of salting conditions can improve the microbiological safety and quality of salted shredded Korean cabbage used for commercial kimchi production.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.397-408
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• 1993

Gas exchange rates and concentrations of ascorbate and glutathlone were measured in needles of eastern white pine(Pinus strohltr) trees differing in foliar sensitivity to ambient oxidant pollution during a ten month period beginning in mid-June, 1988. Current-year needle dry mass and length was 60 to 75% and 45 to 60% less, respectively, in sens~tive trees than in a tolerant tree. Net photosynthesis ($P_n$) and needle conductance ($g_n$) were greatest in the tolerant individual through late September when the rates begin to decline In trees. Needle transpiration rates showed a trend similar to $P_n$ and $g_n$. Ascorbate and total glutathione concentrations in current-year needles increased through the summer and fall, reached a maximum in mid-winter, and then decreased in the spring. Consistently throughout the year, ascorbate concentration was highest in the tolerant tree until the initial springtime decline began in April. The difference In needle ascorbate between the tolerant and sensitive individuals was greater in the summer months (25 to 30%) than in the winter months (8 to 19%). Glutathione content was similar, as was the ratio or oxidized /reduced glutathione, in both tolerant and sensitive trees.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.79-84
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• 1985

This research was attempted in order to develop a long-term storage method for sprouting foods such as potatoes, onions, garlic and chestnuts using Co-60 gamma irradiation combined with a natural low temperature. The sprouting of the irradiated groups, 150 Gy in potatoes, 50 Gy in onions and garlic, and 250 Gy in chestnuts was almost completely inhibited until 8 to 10 months of storage. The rotting rate of loss of weight influenced a little by irradiation with a sprout inhibiting dose, and the weight of loss of the optimum dose irradiated groups was reduced by about 6 to 24% as against that of the nonirradiated in the four stored foods. The chemical components relating to the quality of sprouting foods were better retained in the irradiated groups than in the nonirradiated until the latter period of storage. Therefore, it was shown that the long term storage of sprouting foods is possible using gamma irradiation of 50 to 150 Gy for potatoes, onions, and garlic and 250Gy for chestnuts followed by storage at a natural low temperature($10{\pm}5^{\circ}C$, R.H. 75-85%).

• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.426-435
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• 2010

The present study attempts to compare the soil chemical characteristics and biological activities (i.e. microbial biomass and soil enzyme activities), and litter decomposition rate of Arundinella hirta and Miscanthus sinensis var. purpurascens) collected from serpentine and non-serpentine sites by litter bag techniques at serpentine and non-serpentine field experiment sites over a 9-month period. The serpentine soil showed higher pH and soil alkaliphosphatase activity, and lower soil dehydrogenase and urease activities than the non-serpentine soil. Microbial biomass-N at the serpentine soil was larger than the non-serpentine soil, although the microbial biomass-C and microbial biomass-N represented no significant difference between serpentine and non-serpentine soil. These results suggest that the larger microbial biomass-N caused the lower C/N in serpentine soil. At the end of the experiment, the litter samples of A. hirta and M. sinensis collected from serpentine soil revealed a 39.8% and 38.5% mass loss, and the litter sample from non-serpentine soil also showed a 41.1% and 41.7% mass loss at the serpentine site. On the other hand, at the non-serpentine site, 42.2%, 37.4%, and 46.8%, 44.8% were respectively shown. These results demonstrate that the litter decomposition rate is more intensely affected by the heavy metal content of leaf litter than soil contamination. Moreover, the litter collected from the serpentine soil had a lower C/N, whereas the litter decomposition rate was slower than the litter from the non-serpentine soil, because the heavy metal inhibition activities on the litter decomposition process were more conspicuous than the effect of litter qualities such as C/N ratio or lignin/N. The nutrient element content in the decomposing litter was gradually leached out, but heavy metals and Mg were accumulated in the decaying litter. This phenomenon was conspicuous at the serpentine site during the process of decomposition.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.980-984
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• 2010

Research regarding respiration rate, off-flavor related material and freshness maintenance effect of active MA mini-packaging on perilla leaves has been carried in this study. Respiration rate was highly maintained at high oxygen treatments ($CO_2:O_2:N_2$=0:30:70 and 0:50:50), higher than non-treatment and low oxygen treatments (6:2:92, 0:10:90) during the storage period, and ethylene production was relatively higher. However, off-flavor related materials, acetaldehyde and ethanol production was noticeably low. Weight losses of non-treatment and low-oxygen treatment were about 1.8 and 1.4%, respectively. At the fifth day of storage there was no weight loss. Ascorbic acid content was 13.3 mg/100 g F.W. at the first day of storage. At the third day of storage non-treatment showed the lowest value of ascorbic acid, 8.8 mg/100 g F.W. Ascorbic acid content of active MA treatment gradually decreased without a striking difference as the storage day extended. Chlorophyll content was the lowest at the fifth day of storage with non-treatment, 47.5 (SPAD-502 unit) while the active MA treatment maintained high level of chlorophyll content, 53.0. Sensory evaluation (vision) showed that marketability gradually decreased but was maintained in high oxygen treatments (0:30:70 and 0:50:50), even at the fifth day of storage. Occurrence of off-flavor in non-treatment at the fifth day of storage was extremely low, 2.6; whereas high in high oxygen treatment, 3.4. Active MA packaging maintained freshness two more days at room temperature (about $27^{\circ}C$).