• 한국식품과학회지
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• 제20권1호
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• pp.112-118
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• 1988

배합사료의 단백질원으로 사용되는 13종의 동물성 및 식물성 원료의 미생물 오염 정도와 방사선 조사에 의한 살균 효과 및 이화학적 특성 변화를 조사한 결과는 다음과 같다. 13종의 사료 원료의 호기성 전세균의 오염은 $10^2-10^7/g$ 범위였으며, 5-7kGy 조사로서 3-4 log cycles정도 감소되었고, 어분에서는 10 kGy 조사로서도 $10^1-10^2/g$ 정도 생존하였다. 대장균군은 13종 중 7종에서 $10^4-10^6/g$정도, 장내 병원성 세균은 어분과 가금부산물에서 $10^2-10^3/g$정도 검출 되었고 3-5kGy조사로서 완전 사멸되었다. 곰팡이의 오염은 $10^1-10^4/g$정도로서 오염 곰팡이의 대부분이 내삼투압성 곰팡이였으며 3-7kGy조사로서 검출 한계 이하로 사멸되었다. 또한 이들에서 분리된 곰팡이는 Aspergillus속과 Penicillium속이 대분이였으며 Cladosporium, Aureobasidium과 Rhizopus 등 검출되었으며, 분리된 11종의 곰팡이중 Aspergillus flavus를 포함한 5 여종이 잠재적 독소를 생성하는 균이었다. 총 아미노산 함량, TBA가 및 과산화물가, 색도 등 이화학적 특성 변화에서는 고선량 방사선 조사와 가열처리는 다같이 대조구에 비해 다소의 영향을 미쳤으나 가열처리구는 더욱 현저하였다. 따라서 5-7kGy 정도의 방사선 조사는 사료의 원료의 품질에 영향을 미치지 않고 전세균의 격감과 곰팡이 및 장내 세균를 완전 사멸시킬 수 있어 간접식품으로서 사료의 위생적인 생산을 가져올 수 있을 것으로 생각된다.

• 한국식품저장유통학회지
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• 제24권1호
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• pp.27-35
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• 2017

본 연구는 면역저하 환자용 신선편의 채소류의 위생화를 위해 당근, 오이고추, 방울토마토, 파프리카를 모델식품으로 선정하여 다양한 흡수선량으로 엑스선 조사처리한 후 미생물학적, 이화학적, 관능적 품질 평가를 수행하였다. 당근과 오이고추의 경우 0.4 kGy, 방울토마토와 파프리카의 경우 0.2 kGy 이상의 흡수선량으로 엑스선 조사처리 시 멸균이 확인되었으며, 총 호기성세균 및 대장균군을 제외한 병원균들은 1 log 수준의 검출한계 이하로 나타났다. 모델식품에 접종된 E. coli. L. monocytogenes, S. Typhimyrium에 대한 엑스선의 D10값은 0.11-0.32 kGy로 나타나, 0.4 kGy의 흡수선량을 신선편의 채소류의 멸균을 위한 잠정적인 최소 흡수선량으로 설정하였다. 최대 0.6 kGy의 흡수선량으로 엑스선 조사처리된 신선편의 채소류에 대한 전체 선호도의 경우 7점 척도에서 모두 5.0 점 이상으로 나타나 이들의 관능적 품질이 수용 가능한 수준인 것으로 판단하였다. 또한, 암환자를 대상으로 엑스선 멸균처리(0.4 kGy)된 신선편의 채소류에 대한 선호도 설문조사에서 오이고추와 방울토마토, 파프리카의 경우 모든 항목에 대한 평균 선호도 점수는 5점 척도에서 모두 4.0점 이상으로 나타났다. 따라서 엑스선으로 멸균처리된 오이고추, 방울토마토, 파프리카는 면역력이 저하된 환자들을 위한 위생학적으로 안전한 신선편의 채소로 제공이 가능할 것으로 판단된다.

• 한국축산식품학회지
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• 제39권2호
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• pp.266-275
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• 2019

Although the production of dry-aged beef has been increasing, most purveyors are unaware of the changes in quality that ensue after completion of the aging period and do not adhere to specific guidelines for its packaging and storage. The objective of this study was to investigate the storage stability of vacuum-packaged dry-aged beef based on changes in microbial, physicochemical, and sensory properties during refrigeration at $4^{\circ}C$ for 21 d. The total aerobic bacterial count exceeded 6 Log CFU/g at approximately day 11 and significantly increased after day 14. Freshness indicators such as pH and volatile basic nitrogen content were acceptable until day 14 and 21, respectively. Based on the evaluation of overall sensory acceptability, the dry-aged beef was acceptable until 14 d without any sensory deterioration. Therefore, vacuum-packaged dry-aged beef could be stored for 11 d at $4^{\circ}C$ without any adverse effect on its microbial and sensory quality.

• 한국축산식품학회지
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• 제35권2호
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• pp.205-210
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• 2015

The objective of this study was to develop yogurt-cheese using cow’s milk, ultrafiltrated cow’s milk, and soy milk. The addition of soy milk and ultrafiltrated milk increased the amount of protein in the yogurt-cheese. Yogurt-cheeses were made using cheese base using 10% and 20% soy milk with raw and ultrafiltrated cow’s milk, and stored at 4°C during 2 wk. The yield of yogurt-cheeses made with added soy milk was decreased and the cutting point was delayed compared to yogurt-cheese made without soy milk. Yogurt-cheese made using ultrafiltrated cow’s milk showed the highest yield. However, yogurt-cheese made with added soy milk had higher protein content and titratable acidity than yogurt-cheese made using raw and ultrafiltrated cow’s milk. Fat and lactose contents in the yogurt-cheese made with added soy milk were lower. Yogurt-cheeses made with added soy milk contained several soy protein bands corresponding to the sizes of α₂-, β-, and κ-casein band. Yogurt-cheese made with added soy milk had similar elasticity to yogurt-cheese made without soy milk but had lower cohesiveness. There was no significant difference in the number of lactic acid bacteria in the different cheeses, as all had over 8.0 Log CFU/g. Considering these data and the fact that proteins and fats of vegetable origin with high biological value were observed as well as unsaturated fats, yogurt-cheese made with added soy milk can be considered to be a functional food.

• 한국축산식품학회지
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• 제41권6호
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• pp.950-966
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• 2021

This study investigated the effects of lemon extract powder and vinegar powder on the physicochemical and microbiological characteristics of pork sausages naturally cured using white kimchi powder during storage for 30 days. Six batches were included: control (0.01% sodium nitrite and 0.05% sodium ascorbate); treatment 1 (0.3% white kimchi powder and 0.5% lemon extract powder); treatment 2 (0.3% white kimchi powder and 1.0% lemon extract powder); treatment 3 (0.3% white kimchi powder and 0.5% vinegar powder); treatment 4 (0.3% white kimchi powder and 1.0% vinegar powder); and treatment 5 (0.3% white kimchi powder, 0.5% lemon extract powder, and 0.5% vinegar powder). Treatment 2 had significantly lower pH values and higher cooking loss than the other batches (p<0.05). Treatments 1, 2, and 5 had similar (p>0.05) CIE a^* as the control, while treatments 3 and 4 showed significantly lower values (p<0.05). The residual nitrite content in naturally cured products was lower than the control (p<0.05), while treatments 1 and 2 showed significantly higher nitrosyl hemochrome content and curing efficiency (p<0.05). TBARS values were similar for all treatments and the control (p>0.05). Treatments 1 and 2 showed significantly reduced aerobic plate counts (APC; p<0.05) than the control and other treatments. However, across all batches, TBARS values and APC significantly increased during storage (p<0.05). Our results suggest that lemon extract powder, rather than vinegar powder, may offer a promising alternative for supplementing the functions of nitrite in naturally cured sausages.

• 한국식생활문화학회지
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• 제37권1호
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• pp.61-72
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• 2022

This study investigated the minimum salt concentration required for achieving the optimal quality characteristics of sauerkrauts made by adding 0.5, 1.0, 1.5, 2.0, and 2.5% (w/w) of sea salt to cabbage according to the fermentation period. For evaluating the quality characteristics, we measured the microorganisms (lactic acid bacteria, yeast, and coliform group), pH, total acidity, salinity, chromaticity, and hardness every 24 hours. The lactic acid bacteria were identified and analyzed, and acceptance test was carried out on the 4^th day of fermentation. The results showed that the salinity of 0.5, 1.0, 1.5, and 2.0% sauerkrauts on the 4^th day of fermentation was lower than the average salinity of Baechu-Kimchi. The 0.5, 1.0, 1.5, and 2.0% sauerkrauts had significantly higher lactic acid bacteria than the 2.5% sample, and the coliform group was not detected after the 5^th day of fermentation. Among the microbes identified, Weissella cibaria JCM 12495 was found only in domestic sauerkraut, in addition to Lactococcus lactis NCDO 604, Leuconostoc citreum JCM 9698, and Lactobacillus sakei DSM 20017. The results of the acceptance test show that 1.0 and 1.5% sea salt sauerkraut had significantly higher overall acceptance compared to the other samples. In conclusion, sauerkraut with a salt concentration of 1.0 and 1.5% (w/w) had abundant lactic acid bacteria and excellent sensory properties, suggesting that the production of low-salted sauerkraut can be adopted to reduce consumer salt intake in the future.

• 한국수산과학회지
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• 제51권3호
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• pp.213-220
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• 2018

This study was conducted to investigate changes in the quality of Gochujang following the addition of sea tangle Saccharina japonica powder fermented by lactic acid bacteria (FSP). Gochujang was prepared with or without FSP and fermented at $16^{\circ}C$ for 24 weeks, as detailed in a previous study. No significant physicochemical changes in moisture, crude protein content, pH, salinity and amino nitrogen content were observed among the varieties of Gochujangs evaluated (Commercial Gochujang, Gallic-Gochujang and FSP-Gochujang). In addition, we detected no significant differences in microbiological profiles. However, following addition of FSP to Gochujang, the color was affected and antioxidant properties were enhanced. The DPPH radical scavenging activity of FSP-Gochujang increased by 58.8% and 24.8% compared with Commercial Gochujang and Gallic-Gochujang, respectively. Furthermore, analysis of the free amino acid content revealed higher levels of ${\gamma}$-Aminobutyric acid (100.9 mg/100 g), a biofunctional ingredient, in FSP-Gochujang. Thus, these results suggest the potential for development of a traditional Korean fermented food with enhanced antioxidant activity and ${\gamma}$-Aminobutyric acid content using FSP.

• 한국식품영양과학회지
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• 제24권6호
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• pp.990-997
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• 1995

Effect of preparation method on Yulmoo kimchi(watery kimchi prepared with Yulmoo, leaf radish) fermentation was investigated by measuring physicochemical, microbiological and sensory properties for 20 days. Yulmoo kimchi was fermented at 4$^{\circ}C$ after keeping at room temperature(27$\pm$0.5$^{\circ}C$) for 8 hours. Four types(A, B, C, D) of Yulmoo kimchi were prepared. Sample A was made without wheat flour paste and red pepper powder and sample B was made with wheat flour paste. Sample C was made with red pepper powder, and sample D was made with wheat flour paste and red pepper powder. pH was slowly lowered and stabled after 10 days in all samples. Total acid content increased in all samples. Reducing sugar content initially increased and decreased thereafter. Especially, reducing sugar content of sample B increased in the early stage of fermentation and maintained initial reducing sugar content after 20 days. Total vitamin C content reduced during fermentation in all samples. Especially initial total vitamin C content of sample D increased more than those of other samples relatiely. Lightness and yellowness showed no difference, but on the other hand redness increased gradually in all samples. The number of lactic acid bactgeria reached maximum value in 10~13 days with the total cell numbers and gradually decreased thereafter in all samples. The number of lactic acid bacteria and total cell number of sample D was much more than those of any other samples. As a result of the sensory evaluation, Yulmoo kimchi showed significant difference in all characteristics. Sample D showed the highest scores in all characteristics before 10 days of fermentation. However, after 10 days sample B showed the highest scores.

• 농업과학연구
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• 제39권2호
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• pp.243-253
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• 2012

The objective of the study was to evaluate the quality characteristics of sun-dried Hanwoo beef jerky added with the extract of Citrus junos seib. or Prunus mume. Hanwoo beef shank muscles were sliced, marinated, and sun-dried at $25^{\circ}C$, relative humidity of 35%. The physicochemical quality and microbiological safety of the Hanwoo beef jerky aerobically packaged were analyzed during the storage of $25^{\circ}C$. The moisture content of beef jerky with Citrus junos seib. was the lowest among the treatments after 20 d. Citrus junos seib. and Prunus mume jerky after 10 d had significantly lower aw than those after 0 and 20 d (p<0.05). The pH values of jerky generally ranged from 5.76 to 5.84. The pH value of Prunus mume jerky was significantly higher than those of other jerky samples (p<0.05). Prunus mume jerky showed significantly lower TBARS value than the others after 20 d (p<0.05). Citrus junos seib. jerky showed a significantly lower lightness ($L^*$), redness ($a^*$) and yellowness ($b^*$) than the others during the storage (p<0.05). Prunus mume samples after 10 d had significantly higher $L^*$, $a^*$, and $b^*$ values than the others (p<0.05). With regard to sensory properties, Citrus junos seib. and Prunus mume jerky showed significantly higher flavor and overall acceptability scores than the control (p<0.05). The extracts of Prunus mume will be used in sun-dried Hanwoo beef jerky as a natural agent to retard lipid oxidation and to improve meat color.

• 한국식품영양과학회지
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• 제24권2호
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• pp.330-335
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• 1995

The purpose of this study was to investigate the effects of onion on the physicochemical, microbiological and sensory properties of Dongchimi. Dongchimi with levels(0, 5, 10, 20%) of onion was fermented at twodifferent temperatures : Group A was fermented at 4$^{\circ}C$ and group B was fermented at 4$^{\circ}C$ after fermentation at room temperature(27$\pm$0.5$^{\circ}C$) for 24 hours. During the fermentation up to 45 days, total acidity increased while pH decreased gradually. Total acidity of group B was relatively higher than that of group A. The content of reducing sugar was reached the maximum value in 6 days of fermentation in the group A and on 3 days in the group B. Especially, the highest content of reducing sugar was shown on the Dongchimi added with 5% onion in the group A and 20% onion in the group B. Vitamin C was reduced in the early stage of fermentation, and increased gradually after 10 days. However, vitamin C of Dongchimi without onion increased rapidly in the early stage of fermentation and remarkably decreased thereafter. After 20 days, vitamin C was maintained in Dongchimi added with 10% onion of both two groups. The number of lactic acid bacteria was reached the maximum value on 1 day in the Dongchimi without onion and on 3 days in the Dongchimi added 5, 10 and 20% onion of group A, while gropu B was reached on 1 days and then decreased thereafter. As a result of the sensory evaluation, Dongchimi added 5% onion in the group A showed the highest scores in texture and overall acceptability. Whereas, in the group B, Dongchimi added 20% onion was the most preferable one.