• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1226-1232
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• 2003

Bamboo trees have been used for a long time as folk remedies for treatment of hypertension and stroke symptoms in Oriental regions. These pharmaceutical effects of bamboos look like to be related to its antioxidant capacity and phytochemicals in bamboos. To evaluate the antioxidative effects of bamboo trees, five kinds of bamboo varieties dominant in Korean peninsular were chosen and determined its total antioxidaive activities, free radical scavenging activities and nitrite scavenging activities by TEAC (Trolox Equivalent Antioxidant Capacity) assay, DPPH and Griess reagent assay using in vitro system, respectively. To evaluate the correlation between antioxidative activities and Maillard reaction during hot water extraction, contents of reducing sugar and total nitrogen and brown color intensity at 420 nm were determined. When total antioxidative activities, free radical scavenging activities and nitrite scavenging activities of five kinds of bamboo trees were compared, wang-dae (Phyllostachys bambusoides S. et Z.) showed the strongest effect among samples, although all kinds of extracts showed relatively strong effects against oxidation. The bamboo culms extract showed stronger antioxidative effects than that of bamboo leaves. In each fraction obtained from 70% ethanol extract, antioxidative effect were increased in order of dichloromethane>ethyl acetate>butanol>water>hexane fraction. In reducing sugar analysis of extracts, reducing sugar contents of water extracts were higher than that of 70% ethanol extracts and wang-dae water extract showed the highest level which was 708.92 mg/g. Total nitrogen contents of the extracts were $1.785{\sim}2.605\;mg%$ and contents in water extracts were lower than that in 70% ethanol extracts. Brown color intensity at 420 nm showed similar tendency with results in reducing sugar contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.614-619
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• 1997

To examine effects of drying methods on the formation of N-nitrosamine(NA) in squid during its drying. Three different types of dried products, which were made by sun, hot-air and traditional drying of squid after removal of intestines, were utilized. NA was analyzed by a gas chromatography-thermal energy analyzer. The contents of nitrate and nitrite nitrogen in dried products were in the range of 0 to 5.2mg/kg and 0 to 2.7mg/kg, respectively. The contents of TMAO and betain nitrogen in squid during its drying decreased, while those of TMA and DMA nitrogen increased. The contents in dried products were 27.8~29.2mg% and 10.4~12.3mg/kg, respectively. N-Nitrosodimethylamine (NDMA) was only detected in squid during its drying, recovery from raw sample and its dried pro- ducts spiked with 10$\mu\textrm{g}$/kg for NDPA was 81.0~ 100.0%. NDMA in raw samples was found to be below 0.05$\mu\textrm{g}$/kg. The levels of NDMA in squid increased remarkably during its drying and those in dried products were ranged from 2.7 to 42.7$\mu\textrm{g}$/kg. The effects of drying methods in squid were found to be quite different. the levels of NDMA in traditionally dried products were 11~16 and 3~4 times higher than those in sun dried and hot-air dried products, respectively It is believed that high levels of NDMA were detected in traditionally dried products because NDMA was formed from reaction between various amines and nitrogen oxide produced by combustion of briquet during drying of squid.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.183-187
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• 1991

The effects of microwave heat treatment and addition of enzyme, kimchi liquid, buffer solution and several salts on the changes in pH of kimchi liquid were investigated during fermentation at $25{\sim}35^{\circ}C$. It was found that microwave heat treatment on brined chinese cabbage and enzyme addition of cellulase and amylase showed a little improvement effect, while combination of both methods significantly increased the fermentation rate. The addition of kimchi liquid having pH 4.6 was found to be very desirable for both shortening the fermentation time and flavor acceptance. Among the inorganic salts and buffer solution studied, phosphate buffer(pH 4.6), sodium nitrite and $Na_2HPO_4$ were significantly effective for reduction of kimchi fermentation rate by two to three folds.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.311-314
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• 2001

In order to develop a new Korean traditional liquor using acasia, the condition of alcohol fermentation was investigated by addition of 5%, 10%, 15% nuruk and 10% acasia into mash, The maximum amounts of ethanol was produced when 10% acasia flower and 15% nuruk was added in cooked rice and fermented by S, cerevisiae at $25^{\circ}C$ for 20 days, The acceptability and physiological functionalities of acasia liquors with different concentrations(5%, 10%, 15%, 30%. 50%) of acasia flower were compared. The A -15 liquor which was brewed by addition of 15% acasia flower into mash showed the best acceptability, and its electron-donating ability and nitrite-scavenging activity were also high.

• KSBB Journal
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• v.28 no.3
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• pp.177-184
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• 2013

This research was to investigate the inhibitory effects of tyrosinase, elastase and collagenase using rapeseed meal extract for the functional cosmetics. Gamma-tocopherol and alpha-tocopherol contents were 304.9 and 212.2 mg/kg, respectively. In the case of delta-tocopherol and plastochromanol-8, they were 12.1 and 35.7 mg/kg, respectively. The total phenol content of methanol extract was the highest (49.6 mg/g) which was about 4.96 fold higher than that of water extract. The maximum nitrite scavenging activities of methanol and acetone extract at pH 1.2 were 85.2 and 80.1%, respectively, at 8.0 mg/mL. When the extract concentration of rapeseed meal increased upto 2.0 mg/mL, cell viabilities did not appear to have any significant cytotoxic effect, irrespective of extracts. Tyrosinase and elastase inhibition activities increased from 25.2 to 42.5% and 25.3 to 48.0%, respectively, as methanol extract concentration increased from 0.5 to 1.0 mg/mL. The collagenase inhibition activities of methanol and acetone extracts at 1.0 mg/mL were 67.2 and 68.0%, respectively. These results showed that the methanol and acetone extract of rapeseed meal can be used as a new source of functional cosmetic agent.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.98-104
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• 2017

The objective of this study was to determine the effects of short-term presalting on pink color and pigment characteristics in ground chicken breasts after cooking. Four salt levels (0%, 1%, 2%, and 3%) were presalted and stored for 0 and 3 d prior to cooking. Cooking yield was increased as salt level was increased. However, no significant differences in pH values or oxidation reduction potential (ORP) of cooked chicken breasts were observed. Cooked products with more than 2% of salt level had less redder (lower CIE $a^*$ value) on day 3 than on those on day 0. As salt level was increased to 2%, myoglobin was denatured greatly. Myoglobin denaturation was leveled off when samples had 3% of salt. With increasing salt levels, residual nitrite contents were increased while nitrosyl hemochrome contents were decreased. These results demonstrate that salt addition to a level of more than 2% to ground meat may reduce the redness of cooked products and that presalting storage longer than 3 d should be employed to develop a natural pink color of ground chicken products when less than 1% salt is added to ground chicken meat.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.435-442
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• 2010

The study analyzed the effects of salt concentration [high salt (HS) and low salt (LS)] and sodium nitrite ($NaNO_2$), which are typically utilized in Korean processing facilities, on fatty acid composition, free amino acids, microbial counts and sensory characteristics of processed dry-cured ham. Four different treatments were considered: three hams (11.30 kg) salted with 92 g/kg salt (w/w) (HS), three hams (10.65 kg) treated with HS and 100 ppm $NaNO_2$ (HS+$NaNO_2$), three hams (11.42 kg) salted with 62 g/kg salt (w/w) (LS), and three hams (10.62 kg) treated with LS and 100 ppm $NaNO_2$ (LS+$NaNO_2$). Fatty acid composition analysis revealed significantly (p<0.05) higher saturated fatty acid and lower (p<0.05) unsaturated fatty acid in the HS+$NaNO_2$ group compared with the other groups. Glutamate, alanine and lysine free amino acids were higher than the other free amino acids. The processing conditions did not significantly affect the free amino acids of biceps femoris muscles, except for the proline content (p>0.05). In sensory evaluation, the fermentation aroma of the LS group was higher than that of the HS group. The aerobic counts consistently ranged from from $2.3{\times}10^2$ to $1.11{\times}10^4$ CFU/g. Escherichia coli including strain O157:H7, Staphylococcus aureus, and Salmonella spp. were not detected.

• Journal of Mushroom
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• v.18 no.1
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• pp.53-62
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• 2020

The aims of this study were to investigate the biological activities and amino acid contents of fermentation ethanol and sodium extracts from five edible mushrooms (Pleurotus eryngii, Pleurotus ostreatus, Flammulina velutipes, Lentinula edodes, and Agaricus bisporus). DPPH radical scavenging activities in 30% fermentation ethanol extracts of P. eryngii and P. ostreatus were significantly higher than those in sodium extracts (p<0.05). Nitrite scavenging activities were also higher in the 30% fermentation ethanol extracts of P. eryngii and P. ostreatus. The total polyphenol contents of P. eryngii, P. ostreatus, and F. velutipes were high in 70% fermentation ethanol extracts. The analysis of amino acids revealed that the 70% fermentation ethanol extract of P. eryngii had the highest content of total amino acids, with higher phenylalanine, leucine, isoleucine, valine, and tyrosine contents higher than the other extracts. In all the extracts of P. ostreatus, glutamic acid was the most abundant amino acid. The 5% NaCl and 30% fermentation ethanol extracts of F. velutipes contained abundant glutamic acid, alanine, and proline. Glutamic acid was the most abundant amino acid in the 70% and 30% fermentation ethanol extracts of L. edodes. In the 5% NaCl extracts of A. bisporus, glutamic acid and alanine were abundant. Thus, maximum biological and nutritional ingredients can be extracted using the optimal solvents for each type of mushroom.

• Food Science and Preservation
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• v.13 no.2
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• pp.161-167
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• 2006

This study was investigated to develope health promoting and high quality of mugwort noodle. Mugwort powder was extracted with water and 70% ethanol and the extracts were tested it electron donating ability (EDA), nitrite scavenging ability (NSA) and inhibitory effects on MDA cell and A549 cell. EDA at 100-1,000 ppm of water extract was ranged f개m 73% to 81% and that of ethanol extract was ranged from 74% to 92% NSA of water extract was 40% and ethanol extract was 41% at 1,000 ppm, which were the highest at pH 1.2. NSA was increased with increasing conncentration of mugwort extracts and decreasing pH. Inhibition ratio of water and ethanol extracts on MDA cell growth was 30 and 27% while that on A549 cell was 22% and 23% at 1,000 ppm, respectively. Quality characteristics of mugwort none were evaluated by their color, shelf life na sensory characteristics. Lightness (L) and redness(a) of dried noodle and cooked noodle were decreased with increasing mugwort concentration(p<0.05). The number of total viable cells and fungi in mugwort noodle was $0.5{\sim}0.7log$ cycles lower than that of contro. In sensory evaluation of dried noodles and cooked noodles, noodles with 2% mugwort powder had significant high scores in overall acceptability.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.332-336
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• 1998

The effect of ripening temperature, pH and salinity on the formation of Nnitrosamine (NA) during Kimchi fermentation and in vitro was studied, respectively. During Kimchi fermentation for six weeks at cold storage temperature ($4^{\circ}C$) and room temperature ($16{\pm}2^{\circ}C$), the contents of nitrite and dimethylamine (DMA) showed variation at room temperature but no variation at cold storage temperature. The maximum generation of nitrosodimethylamine (NDMA) resulted low content ($2.69\;\mu\textrm{g}/kg$) at cold storage temperature but started to increase after one week fermentation and reached to the 18-fold higher generation ($49.6\;\mu\textrm{g}/kg$) at room temperature. During Kimchi fermentation, no correlation was observed between the variation of nitrite and DMA content and the generation of NDMA. However, pH showed effective relation to NDMA generation such as the highest NDMA generation was obtained at lowest pH 4. During in vitro test, higher temperature and lower pH resulted more NDMA generation and generation amount was affected more by pH. Also, the salinity of Kimchi provided inhibitory effects on the formation of NDMA. NDMA was produced $5.86\;\mu\textrm{g}/kg$ at normal salinity (2.5%) but $90.9\;\mu\textrm{g}/kg$ at lower salinity (15%) after three week. The higher salinity showed lower formation of NDMA in vitro test, too.