• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.609-614
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• 2006

Quality changes in mustard leaf kimchi were investigated during storage for 60 days at $5^{\circ}C$. As the storage period changed from 0 to 60 days, the pH and reducing sugar content of mustard leaf kimchi decreased, while the total acidity and hunter's color increased. The vitamin C content in mustard leaf kimchi decreased gradually from 10 to 30 days and then markedly increased after 40 days. The total dietary fiber content and antioxidative activity were significantly higher in fresh mustard leaf kimchi than in fermented kimchi. The major volatile components of mustard leaf and mustard leaf kimchi were determined to be allyl isothiocyanate, 3-butenyl isothiocyanate and phenylethyl isothiocyanate. The contents of allyl isothiocyanate and phenylethyl isothiocyanate, the two major functional components, in mustard leaf kimchi were determined to be 43.72 and $36.17\;{\mu}g/g$ dry weight basis, respectively.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.299-307
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• 2007

Changes in nitrite content, TBARS content and color of meat products during storage were examined as part of studies addressing the reduction of residual nitrite and to ensure the safety of meat products. All 4 kinds of domestic meat product tested, Vienna sausage, bacon, smoked-ham and Dduggalbi, manufactured by C and L domestic companies had very low contents of residual nitrite, for below the legal tolerance limit of 70 ppm, and the residual nitrite decreased with storage. The reduction in nitrite content differed with each product, showing the greatest reduction in Vienna sausage and the least reduction in bacon when stored at $4^{\circ}C$. On the other hand, when stored at $-20^{\circ}C$, the nitrite content of bacon decreased more rapidly than the other meat products. The results of this study show that the nitrite content of meat products decreases during storage, and that the rate of decrease is quite dependent on the storage temperature. In addition, the nitrite contents of most domestic meat products are very low compared to the legal limits, thus the health risks of nitrite in meat products might not be of great concern. More research on the reduction of residual nitrite and on the development of alternatives to nitrite is necessary.

• Journal of Mushroom
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• v.19 no.1
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• pp.14-22
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• 2021

This study investigated the changes in the antioxidant activity, nitrite scavenging activity, and ��-glucan content of processed raw materials (Pleurotus eryngii, Pleurotus ostreatus, Lentinula edodes, and Flammulina velutipes) brought about by storage at room temperature (20-25℃) and low temperature (4℃). The results indicated that DPPH free radical scavenging activity was the lowest in air-dried and roasted samples that were stored at room temperature, k with the exception of the air-dried samples of P. eryngii and L. edodes. For total polyphenol contents, all roasted samples of the edible mushrooms stored at room and low temperature decreased compared with the samples pre-storage, except for the air-dried samples of P. eryngii, P. ostreatus, and L. edodes. Furthermore, the ferric reducing antioxidant power and reducing power of the air-dried and roasted samples stored at room temperature and low temperature tended to increase compared to that before storage. Moreover, the ��-glucan content in the air-dried and roasted samples stored at room temperature was significantly lower compared to that before storage, as well as to that in the samples stored at low temperature (p<0.05). The results of this study may help predict the degree to which biological activities in processed edible mushrooms change when stored at room temperature and/or low temperature conditions.

• Food Science and Preservation
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• v.22 no.3
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• pp.303-313
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• 2015

This study investigates the physicochemical, microbiological and sensory characteristics of seasonal salted-Kimchi cabbages to provide basic data on its uniform quality. Generally, seasonal salted-Kimchi samples had different pH values at initial storage periods, but there was no difference in pH between the seasonal samples when stored for longer periods. The samples from the fall and winter seasons were relatively low in acid and high in solid soluble content compared to samples from other seasons. Salted-Kimchi cabbages in the summer showed the highest microbiological number compared to samples from other seasons. In the sensory evaluation, there were differences in the appearance, aroma, and taste, depending on seasonal samples at different storage periods. The correlation coefficient between the quality characteristics in the seasonal samples showed a positive or negative correlation between the quality characteristics at 1% significant level. In the principal component analysis, F1 and F2 were shown the 51.81% and 14.23% of the total variance (66.21%), respectively. In the PCA pattern of seasonal salted-Kimchi cabbages during storage periods, winter samples were distributed on the top of F2, spring samples were in the middle of F2, while the rest of the samples were distributed on the bottom of F2. According to increasing storage periods, initial storage samples were distributed at the left of F1, while other samples were located at the right of F2.

• Korean Journal of Poultry Science
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• v.38 no.4
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• pp.265-273
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• 2011

This study was carried out to determine the effect of dietary supplementation of quercetin and methoxylated quercetin extracted from onions on chicken thigh meat quality during cold storage. For 35 days, 1-day-old 320 broiler chicks (Ross) were divided into 8 groups and supplemented the diet; basal diet only (CONTROL), CONTROL with antibiotics (AB), vitamin E 20 IU (VE20), vitamin E 200 IU (VE200), quercetin 20 ppm (QC20), quercetin 200 ppm (QC200), methoxylated quercetin 20 ppm (MQ20), and methoxylated quercetin 200 ppm (MQ200). After slaughtering the broilers, thighs were separated and analyzed the quality change of the meat during storage at $4^{\circ}C$ for 7 days. The meat quality factors such as pH, color, water holding capacity, and sensory characteristics of thigh meat were determined on the experiment day 0, 3, and 7. After slaughtering, the pH of AB, VE 20, QC 20, and MQ 200 showed no significant difference compare to that of CONTROL. However, VE 200 and QC 20 showed higher pH value than CONTROL on storage day 3. $L^*$ value of chicken thigh of MQ 20 was lower than CONTROL on storage day 0, however, no significant difference was found between CONTROL and treatments on storage day 3. Redness ($a^*$) of chicken thigh in CONTROL was increased during storage. QC 20, QC 200, and MQ 200 significantly reduced the $b^*$ value of chicken thigh (p<0.05). Water holding capacity of VE 20 and MQ 200 was significantly higher than the CONTROL on the day 0. Also, QC 200 showed higher WHC compare to the CONTROL. In sensory evaluation, overall acceptability of chicken thigh in quercetin and methoxylated quercetin group showed no significant differences compare to that of CONTROL by storage day 3. These results suggested that the quercetin and methoxylated quercetin could be used as additives to enhance broiler thigh meat quality such as pH and WHC without adverse effect on color and sensory characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.896-901
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• 2007

This study was carried out to investigate the effect of the addition of olive and soybean oil on the color, water holding capacity, cooking loss, increase rate of thickness, decrease rate of diameter, pH, VBN content and TBARS value of ground pork loin during cold storage for 15 days. Ground pork loin were prepared by three types such as ground pork loin containing 20% pork fat (GP-P), ground pork loin containing 20% olive oil (GP-O) and ground pork loin containing 20% soybean oil (GP-S). The $L^{\ast}$ (lightness) and $b^{\ast}$ (yellowness) value of GP-P, GP-O and GP-S were not significantly different during storage, and the $L^{\ast}$, $a^{\ast}$ and $b^{\ast}$ value of GP-P were higher than those of GP-O and GP-S (p<0.05). The water holding capacity tended to increase along with storage period, the water holding capacity of GP-P was higher than that of GP-O and GP-S. Also, the cooking loss of GP-P was lower than that of GP-O and GP-S (p<0.05). The increase rate of thickeness by cooking increased along with storage period, but the decrease rate of diameter was tend to decreased with increase in storage period (p<0.05). The pH of all ground pork loins decreased until storage at 5 days, but increased at 15 days (p<0.05). The VBN content of all ground pork loins increased along with storage period, and the VBN content of GP-P was higher than that of GP-O and GP-S (p<0.05). The TBARS value of all ground pork loins increased along with storage period; also, the VBN content of GP-P was the highest among all ground pork loins and GP-O was the lowest among all ground pork loins (p<0.05).

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.04a
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• pp.29-40
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• 2002

감잎으로부터 통풍치료, 미백효과, 고혈압 억제효과의 개발목적으로 9종의 flavan-3-ol 화합물을 분리하였고 기기분석에 의해 화학구조를 자혔다. 각 화합물은 (+)-catechin (+)-gallocatechin procyanidinB-l, pyrocyanidin C-1, prodelphinidin B-3, gallocatechin-(4$\alpha$$\longrightarrow$8)-catechin과 감나무 잎에서 새로운물질인pocyanidin B-7-3-0-gallate, procyanidin C-1-3'-3" -3.'S _0-trigallate, (-)-epigallocatechin-(4 $\beta$ -18)-epigallocatechin-(4$\beta$-'8)-catechin 3종류를 발견하였다. 감잎으로부터 순수 분리한 polyphenol류의ACE 저해활성측정을 실험한 결과 pocyanidin B-7-3-0-gallate는 100rM농도에서 94%의 저해효과를 나타내었으며 epigallocatechin-(4$\beta$$\longrightarrow$8)-epigallo-catechin-(4$\beta$$\longrightarrow$8)-catechia procyanidin C-1-3'-3" -3f'.-0-trigallate는 각각 90.69, 80.90% 저해를 하였다. Xanthine oxidase 저해활성측정을 조사한 결과pocyanidin B-7-3-0-galtate와 pocyanidin C-1-3'-3" -3/'S _0-trigallate 즉, gallate가 붙은 호합물에서100rM의 농도에서 66%와 63%의 강한 저해효과를 나타났다. Tyrosinase 저해활성을 측정한 결과는pocyanidin C-1-3'-3" -3.'S _0-trigallate는 100rM에서 70%의 강한 저해효과를 나타냈으며,epigallocatechin-(4$\beta$$\longrightarrow$8)-epigallo-catechin-(4$\beta$$\longrightarrow$8)-catechin는 51%의 저해효과를 나타내었다. 산업적응용을 위해 분획한 폴리페놀군은 미백효과 검증실험인 tyrosinase 저해율 측정평가에서 폴리페놀 함량이 가장 높은 Fraction 111의 경우 Sooppm에서 74.2%의 높은 저해율을 나타내었다. 항산화력 실험에서는500pw1이상에서 강한 활성능을 보인 SOD 유사활성능을 제외한 나머지 DPPH와 xanthine oxidase 저해효과에서는 Fraction II와III 모두가50ppm이상에서 80% 이상의 높은 유리라디칼 소거능력을 나타내었다. 그리고 각 Fraction별 항균력 측정 결과 Fraction 르와 111이 우수하게 나타났고 항균활성은 그람음성균보다 그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.

• Food Science and Preservation
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• v.5 no.3
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• pp.256-261
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• 1998

To investigate the function and effectiveness of natural antimicrobial agent(NAA), as freshness preserving material, extracted from medicinal herbs, their antimicrobial activities were tested against Bacillus cereus, Corynebacterium xerosis, Peudomonas syringae and Enterobacter aerogenes causing the postharvest decay of greenhouse produce. The ethanol extracts of Polygonum cuspidatum Sieb. et Zucc and Syzyrium aromaticum (L.) Merr. et Perry showed remarkable inhibitory effect on the growth of above-mentioned reference microorganisms when treated with mon than 500ppm. The antimicrobial activities of NAA were very stable in the wide spectrum of temperature (40$^{\circ}C$-180$^{\circ}C$) and pH(4-10).

• Food Science and Preservation
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• v.22 no.4
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• pp.577-584
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• 2015

The objective of this study was to investigate the antioxidant activity of imported tropical and subtropical fruits including dragon fruits, green kiwi, papaya, pineapple, pomegranate, and yellow mango. A seventy percent of ethanol extracts were prepared. Total phenolic content, DPPH (1,1-diphenyl-2-picryl hydrazyl)-, ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)), superoxide anion radical scavenging activity, FRAP (ferric reducing antioxidant power), tyrosinase inhibitory activity, and reducing power were investigated for the comparisons of antioxidant activities. The phenolic content expressed as gallic acid equivalents (GAE) was found to be highest in pomegranate (12.22 mg GAE/g), followed by pineapple (3.77 mg GAE/g). Pomegranate and pineapple exhibited higher antioxidant activity than those of other fruits except for FRAP. DPPH and ABTS radical scavenging activity from pomegranate were 93.00%, and 98.98%, respectively, at a concentration of 5 mg/mL, which were equal to those of ascorbic acid used for a positive control.

• Food Science and Preservation
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• v.9 no.4
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• pp.369-374
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• 2002

This study was performed to investigate the effects of tyrosinase inhibition, xanthine oxidase inhibition and nitrite-scavenging effects of gamma-irradiated Schizandrae Fructus extracts from different solvents. Schizandrae Fructus was extracted by hot water, ethanol, acetone and methanol, and the extracts were irradiated 10, 20 and 30 kGy with gamma rays. All extracts from Schizandrae Fructus showed inhibition effect against tyrosinase. Tyrosinase inhibition effect of Schizandrae Fructus were higher in solvent extracts than hot water extracts by irradiation. The Schizandrae Fructus extracts had a higher inhibitory effect against xanthine oxidase, and the effect was not changed by irradiation. Nitrite scavenging activity, which was measured at various pH conditions (1.2, 3.0, 6.0), was the highest in Schizandrae Fructus extracts at pH 1.2 and 3.0. Hot water extracts provided higher nitrite scavenging effect than those of the methanol, ethanol and acetone extracts. Gamma-Irradiation may not influence on biological activites of the extracts when irradiated up to 30 kGy.