• 한국축산식품학회지
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• 제42권4호
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• pp.580-592
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• 2022

The aim of the present study was to evaluate the effectiveness of Lycium barbarum polysaccharide (LBP) on lipid oxidation and protein degradation in Tan sheep meatballs during the frozen period. The meatballs were treated with LBP at 0.01%, 0.02%, and 0.03% and stored at -18±1℃ for 0, 3, 6, 9, and 12 weeks. The effects of LBP treatment were investigated using the contents of total volatile basic nitrogen (TVB-N), texture profile (TP), thiobarbituric acid reactive substances (TBARS), colour, and pH values, compared with 0.02% butylated hydroxytoluene treatment and the blank control. The results showed that LBP treatment significantly decreased TBARS content compared with the control, which confirmed LBP to be a highly effective component in preventing lipid oxidation of Tan sheep meatballs during frozen storage, and protein degradation in Tan sheep meatballs had a significant inhibition effect because of TVB-N value reduction. In addition, the colour, TP and pH values of meatballs treated with LBP were improved dramatically. To further determine the quality changes of the blank control and all treated groups during storage, the comprehensive score evaluation equation based on principal component analysis was obtained: Y=0.51632Y₁+0.29589Y₂ (cumulative contribution rate=81.221%), and the 0.02% LBP-treated group had a higher comprehensive score than the other groups, and the quality of LBP-treated meatballs was better as well. In summary, LBP may reduce or inhibit lipid oxidation and protein degradation, and enhance overall quality and shelf-life in prepared meat products.

• 한국축산식품학회지
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• 제42권6호
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• pp.953-967
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• 2022

The objective of this study was to determine effects of aging methods (wet-aged, dry-aged, and packaged dry-aged) during 60 d on quality traits and microbial characteristics of beef. Wet-aged beef was packed by vacuum packaging and stored in a 4℃ refrigerator. Dry-aged beef was used without packaging. Packaged dry-aged beef was packaged in commercial bags. Dry-aged and packaged dry-aged samples were stored in a meat ager at 2℃-4℃ with 85%-90% relative humidity. Meat color, crust thickness, aging loss, cooking loss, Warner-Bratzler shear force (WBSF), texture profile analysis, Torrymeter, meat pH, water activity, volatile basic nitrogen (VBN), thiobarbituric acid reactant substances (TBARS), and microbial analysis were measured or performed every 15 d until 60 d of aging time. Meat color changed significantly with increasing aging time. Differences in meat color among aging methods were observed. Aging losses of dry-aged and packaged dry-aged samples were higher than those of wet-aged samples. Wet-aged beef showed higher cooking loss, but lower WBSF than dry-aged and packaged dry-aged beef. VBN and TBARS showed an increasing tendency with increasing aging time. Differences of VBN and TBARS among aging methods were found. Regarding microbial analysis, counts of yeasts and molds were different among aging methods at the initial aging time. Packaged dry-aged and dry-aged beef showed similar values or tendency. Significant changes occurred during aging in all aging methods. Packaged dry aging and dry aging could result in similar quality traits and microbial characteristics of beef.

• 한국축산식품학회지
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• 제43권5호
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• pp.840-858
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• 2023

This study was designed to compare the quality changes in mackerel fillets stored under different conditions by using hyperspectral imaging (HSI) techniques. Fillets packaged in vacuum were stored for six days under five different conditions: refrigerated at 4℃ (R group); iced at 5±3℃ (I group); kept at an ambient of 17±2℃ (A group); frozen at -18℃ for 24 h and thawed in a refrigerator at 4℃ for 5 h on the sampling day (FTR group); FTR thawed in tap water instead of thawing in a refrigerator (FTW group). The FTR group had the lowest total bacterial count, drip loss, 2-thiobarbituric acid reactive substances, volatile basic nitrogen, and texture profile analysis values among groups during the entire storage period (p<0.05). Scanning electron microscopy revealed that the FTR group had less damage, while the other groups had shrunken muscle tissues. HIS integrated with the partial least squares model yielded reliable and efficient results, with high R²_cv values, for several quality parameters of the mackerel fillets. Overall, the FTR group, involving freezing and thawing in a refrigerator, appears to be the most favorable option for maintaining the quality of mackerel fillets, which could be practically implemented in the industry. HSI is a suitable and effective technique for determining the quality of mackerel fillets stored under different conditions.

• Animal Bioscience
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• 제35권9호
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• pp.1367-1378
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• 2022

Objective: The present study was conducted to examine the gas production, fermentation characteristics, nutrient degradation, and methanogenic community composition of a rumen fluid culture with Broussonetia papyrifera (B. papyrifera) subjected to ensiling or steam explosion (SE) pretreatment. Methods: Fresh B. papyrifera was collected and pretreated by ensiling or SE, which was then fermented with ruminal fluids as ensiled B. papyrifera group, steam-exploded B. papyrifera group, and untreated B. papyrifera group. The gas and methane production, fermentation characteristics, nutrient degradation, and methanogenic community were determined during the fermentation. Results: Cumulative methane production was significantly improved with SE pretreatment compared with ensiled or untreated biomass accompanied with more volatile fatty acids production. After 72 h incubation, SE and ensiling pretreatments decreased the acid detergent fiber contents by 39.4% and 22.9%, and neutral detergent fiber contents by 10.6% and 47.2%, respectively. Changes of methanogenic diversity and abundance of methanogenic archaea corresponded to the variations in fermentation pattern and methane production. Conclusion: Compared with ensiling pretreatment, SE can be a promising technique for the efficient utilization of B. papyrifera, which would contribute to sustainable livestock production systems.

• 한국축산식품학회지
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• 제44권1호
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• pp.189-203
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• 2024

This study investigated the antioxidant activity of radish seed oil (RSO) and its effects on the quality and storage characteristics of pork patties. To assess the antioxidant capacity of RSO, this study analyzed fatty acid composition, peroxide value (PV), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. Pork patties were manufactured with the addition of RSO-0.4%, 0.8%, 1.6%, and 2.4%-and measured in terms of proximate composition, pH, water holding capacity (WHC), cooking loss (CL), color, texture profile analysis, and a sensory evaluation. Total microbial count (TMC), volatile basic nitrogen (VBN), thiobarbituric acid reactive substances (TBARS), and PV were measured at 1, 3, and 7 days of refrigerated storage. The DPPH radical scavenging activity of RSO was found to be 75.46%. In the cases of WHC and CL, there was no significant differences observed between RSO0.4%, RSO0.8%, and positive control (PC; p>0.05). Meanwhile, RSO2.4% showed significantly lower hardness, springiness, gumminess, and chewiness than PC (p<0.05), and these values tended to decrease with the addition of increasing RSO. In terms of storage characteristics, with an increase in the amount of RSO added, TMC, VBN, TBARS, and PV all decreased; among the treatment groups, RSO2.4% showed the lowest values. In conclusion, RSO exhibits antioxidant activity, but when added in large amounts, it negatively affects the quality characteristics of patties while positively impacting their storage properties, thus necessitating a balanced consideration of both outcomes. Therefore, adding 1.6% RSO is considered to be the most appropriate level for formulations to be used in practice.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.654-662
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• 2024

To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation. Strains belonging to Mucoromycota, including Lichtheimia, Mucor, Rhizomucor, and Rhizopus, produced smaller amounts of total amino acids and umami-producing amino acids, such as glutamic acid and aspartic acid, than strains belonging to Aspergillus subgenus circumdati. The genera Penicillium and Scopulariopsis produced large amounts of total amino acids and glutamic acid, suggesting that these genera play an essential role in producing umami and kokumi tastes in fermented soybean products. Strains belonging to Aspergillus subgenus circumdati, including A. oryzae, showed the highest amino acid content, including glutamic acid, suggesting the potential benefits of A. oryzae as a starter for soybean fermentation. This study showed the potential of traditional meju strains as starters for soybean fermentation. However, further analysis of processes such as the production of G-peptide for kokumi taste and volatile compounds for flavor and safety is needed.

• 한국식품영양과학회지
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• 제34권8호
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• pp.1239-1245
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• 2005

노지 및 시설에서 재배된 한라봉의 과피에서 냉압착법에 의해 추출한 정유의 향기성분을 동정하였다. 노지에서 재배된 한라봉 정유에서 44개의 향기성분(99.7$\%$)이, 시설 한라봉 정유에서 45개의 성분(99.4$\%$)이 동정되었으며, (E)-lim-onene-1,2-epoxide와 neral은 노지 한라봉 정유에서만 동정되었고, $\beta$-cubebene, $\beta$-elemene, decyl acetate의 세 성분은 시설 한라봉 정유에서만 동정되었다. 노지 및 시설 한라봉 정유에서 동정된 향기성분 중 limonene이 86$\%$이상의 가장 높은 비율로 함유된 성분으로 확인되었으며, 그 다음으로 myrcene과 sabinene이 2$\%$이상으로 높게 함유된 것으로 확인되었다. 노지 및 시설 한라봉 정유의 향기성분 특성을 나타내는 가장 큰 차이는 linalool의 함유량으로 노지 한라봉 정유의 함유량(1.2$\%$)이 시설정유의 함유량(0.5$\%$)의 2배 이상으로 높았다. 향기 성분의 기기분석과 함께 신선한 한라봉 과육 및 과피의 관능평가를 실시하였다. 신선한 한라봉의 향기특성에 대한 관능평가 결과는 한라봉 과육 및 과피 모두에서 노지에서 재배된 한라봉이 시설에서 재배된 것에 비해 상대적으로 강한 향기특성을 지니는 것으로 평가되었다. 노지 한라봉 과육은 단맛이, 시설 한라봉 과육은 신맛이 유의적으로 높게 평가되었다. 또한, 향과 맛을 고려한 전체적 선호도에서도 노지에서 재배된 한라봉이 높게 평가되었다. (p<0.01).이러한 결과는 노지 한라봉 정유에서 유의적으로 높은 linalool의 함유율 및 재배방법의 영향을 받은 향기성분의 구성비율이 관능평가에 의한 과피 및 과육의 향기특성 결과에 영향을 주는 것으로 판단되었다.

• 미생물학회지
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• 제51권3호
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• pp.300-307
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• 2015

좋은 청국장을 발효하는 균주를 선발하기 위하여 청국장 시료로부터 8개의 균주를 선발하였다. 이들 중 7균주는 Bacillus subtilis subsp. subtilis와 99.9% 이상의 가장 높은 16S rRNA 유사도를 보였고, 한 균주는 B. licheniformis와 높은 유사도를 보였다. 선발 균주의 효소 생성을 분석한 결과 모든 균주에서 amylase, cellulase, protease 그리고 lipase 활성을 보였고, 6균주에서 혈전용해능을 보였다. 또한 전통방법으로 제조한 청국장에서 분리한 균주들의 안전성을 확보하고자 분리균주와 계통학적으로 가까운 Bacillus cereus의 독소유전자 7종의 유무를 확인한 결과 모든 선발균주에서 독소유전자 7종을 가지고 있지 않았다. 선발 균주 중 8균주에서 histamine과 tyramine의 생성이 없거나 최소한의 생성을 보였고, HPLC를 이용한 바이오제닉 아민 분해능 분석 결과 대부분의 균주가 tyramine 분해능을 보였다. 선발된 균주로 발효한 청국장의 발효능, 관능, 휘발성염기질소 생성을 확인 하여 7균주가 좋은 품질의 청국장을 만드는 것으로 확인되었고, 이들 선발된 균주로 만든 청국장의 metabolic profile을 분석하였다.

• Applied Biological Chemistry
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• 제36권5호
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• pp.346-351
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• 1993

영양학적 특성이 우수하면서도 선도유지가 어려워 사료로 다량 이용되고 있는 정어리를 우리나라사람들의 기호에 맞게 항산화제가 함유된 조미식초용액에 절임을 하여 저장 중 품질안정성에 대하여 실험하였다. 저장 중 정어리 초절임제품의 수분함량은 전제품이 거의 변화가 없었고, pH, 휘발성염기질소함량 및 아미노태질소함량은 모두 증가하는 경향을 나타내었으며, 증가폭은 항산화제를 처리하여 저온에 저장한 제품이 가장 적었다. 생균수 및 histamine함량은 항산화제의 처리유무와 관계없이, 저온저장함으로서 저장 중 변화를 억제할 수 있었다. TBA값, 과산화물값 및 혼합지방산조성의 결과로 미루어 볼 때 항산화제를 첨가한 조미식초액에서 초절임을 하여 저온저장함으로써 저장 중 지질산화를 효과적으로 억제가 가능하였다. 텍스튜어의 경우 저장 중 경도 및 질김성이 감소하였고, 그 정도는 항산화제의 처리유무에 관계없이 저온저장한 제품이 가장 적었으며, 탄성 및 응집성은 제품의 종류에 관계없이 거의 변화가 없었다.

• 한국식품영양과학회지
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• 제33권8호
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• pp.1337-1342
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• 2004

현재 대부분의 굴비는 마른간법을 이용한 방법이 사용되고 있다. 마른간법은 제조 과정인 섞기에 있어서 조기의 상처가 발생할 뿐만 아니라 품질이 균일하지 못한 단점이 있다. 물간법을 이용하여 굴비를 가공할 때 상승효과를 위해서 10% 양파즙, 10% 마늘즙, 또는 양파즙과 마늘즙을 동량혼합한 것을 10% 첨가하고 12일간 상온에서 저장하면서 TVB-N, TBARS, TMA, 총균수변화를 관찰하였다. 분석 결과 마늘과 양파 혼합즙액으로 처리한 제품에서의 TVB-N 값은 88.2 mg/100 g, TMA와 TBARS는 각각 14.13 mg/100 g과 3.1$\mu$mol/kg으로 여러 처리구 중 가장 낮은 값을 보여주었다. 굴비의 지방산 조성은 30일간 저 장하면서 생조기, 염장조기, 마늘과 양파 혼합즙액을 처리한 염장조기에 대하여 지방산의 변화를 살펴본 결과 생조기와 굴비 모두 포화지방산의 비율은 32∼35%로 나타났으며, 포화지방산 중 가장 많은 비율을 차지하는 것은 palmitic acid로 21∼23%였다. 불포화지방산 중 이중결합이 1개인 monoenes의 비율은 39∼45%범위로 oleic acid가 가장 많은 비율을 차지하였다. 다가 불포화지방산의 비율은 생조기는 14%였으나 5일 건조한 것은 15∼19%로 나타났다. 저장 30일째 $\omega$-3계 지방산인 docosahexaenoic acid, eicosapentaenoic acid에 있어서 염장 않은 굴비는 7.37%와 3.71%를 보여 주었으나, 물간법에 의한 굴비는 9.46%와4.08%, 마늘 양파 혼합즙액이 함유된 물간법으로 제조된 굴비에서는 9.91%와 4.25%로 높게 나타났다.