• 한국축산식품학회지
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• 제43권6호
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• pp.1170-1182
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• 2023

The aim of this study was to determine the effect of chitosan (CH)-based nanocomposite coating applications [chitosan+TiO₂ (CHT) and chitosan+TiO₂+rosmarinic acid (CHTRA)] on changes in quality attributes of rainbow trout fillets during cold storage (4℃). Fish fillets were randomly divided into four groups and subjected to treatments (CH, CHT, CHTRA, and control). After treatments, the groups were packaged under a modified atmosphere (40% CO₂+30% O₂+30% N₂) and stored at 4℃ for 18 days. During cold storage, the samples were subjected to physico-chemical and microbiological analyses. During storage, CH, CHT, and CHTRA treatments showed lower aerobic mesophilic and psychrotrophic bacteria counts than the control. However, the differences between coating treatments were not significant. The highest mean pH value was determined in the control group. As the storage time increased, the thiobarbituric acid reactive substances value increased. At the end of the storage period, no significant differences were observed between the treatments, including in the control group. The total volatile basic nitrogen (TVB-N) level in the control group was above 25 mg/100 g on day 15 of storage. However, the TVB-N level in the treatment groups was below 20 mg/100 g on day 18. It was also determined that coating application×storage period interaction had a significant effect on all color parameters (p<0.01). At the end of storage, the highest CIE L* was observed in CHTRA treatment. However, the value of this treatment did not differ from that of the CH treatment.

• 한국초지조사료학회지
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• 제40권3호
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• pp.182-189
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• 2020

This study was conducted to evaluate the effect of lactic acid bacteria (LAB) inoculation to domestically-cultivated Italian ryegrass (IRG) on silage fermentation and in vitro ruminal fermentation. There were six treatments based on the LAB inoculants: 1) no addition of LAB (negative control: NC), additions of 2) commercially-available LAB (positive control: PC), 3) Lactobacillus plantarum (LPL), 4) L. paracasei (LPA), 5) L. acidophilus (LA), and 6) L. pentosus (LPT). All treatments were inoculated at a concentration of 10⁶ CFU/g and ensiled for 3, 7, 21, and 42 days in triplicate and analyzed for nutritive values when ensiling was terminated. Day 42 silage from all treatments were also examined for in vitro ruminal fermentation. After 42 days, LAB-inoculated silages had higher (P<0.05) lactic acid concentration compared to the NC. In terms of nutritive values, the silages treated with LPA, LA, and LPT showed higher (P<0.05) crude protein and lower (P<0.05) neutral detergent fiber and acid detergent fiber content compared to the rest of the treatment. In vitro ruminal dry matter degradability was not affected by LAB addition. However, LAB-treated IRG had shown higher (P<0.05) ammonia-N compared with that of the NC. LPA had shown the highest (P<0.05) volatile fatty acid concentration among the LAB examined. In conclusion, the addition of a single strain of LAB appeared to produce a quality IRG silage compared with the NC and the PC. Among the strains examined, LPA seemed to be superior to the others.

• 한국초지조사료학회지
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• 제31권2호
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• pp.177-190
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• 2011

본 연구는 허브 부식토를 이용하여 첨가 수준별 in vitro 반추위 발효특성 평가와 젖소를 이용하여 급여시 유생산성에 미치는 영향을 조사하기 위하여 본 연구를 수행하였다. 시험 1에서는 티머시 건초를 기질로 하여 허브부식토(herbaceous peat)를 0,1 및 5%를 3반복으로 각각 첨가하여 in vitro 반추위내 pH, 가스발생량, VFA (volatile fatty acid), ammonia-N 및 건물분해율을 조사하여 반추위내 발효성상의 변화를 평가하였다. pH 변화는 0, 3, 12 및 24시간 배양에 있어서 모든 처리구에서 유의한 차이를 보이지 않았지만 6시간. 대조구에서 1 및 5% 첨가구와 비교하여 유의하게 낮은 pH를 나타냈다(p<0.05).가스 발생량은 배양 12시간까지 처리구에서 대조구와 비교하여 유의하게 증가 하였으며(p<0.05), 반추위액내 암모니아 농도는 모든 처리구에서 24시간까지 증가하는 경향을 나타냈으며, 처리간 유의한 차이는 없었다. 건물분해율은 모든 시간에서 5%구가 대조구 및 1%구와 비교하여 건물분해율이 높았다(p< 0.05) 따라서 허브부식토를 0, 1 및 5% 수준으로 각각 첨가하여 반추위내 in vitro 배양시간 별 반추위 발효특성은 대부분 조사항목에서 처리구가 대조구에 비해 개선효과를 나타냈으며, 시험 2에서는 젖소를 이용하여 사양시험을 통해 유생산성을 평가하였으며, 우유생산량 변화와 유성분 및 체세포 수 변화를 조사하기 위해 홀스타인 착유우 16두를 공시하여 4주간 사양 시험을 실시하였다. 산유량은 T3구가 25.0 kg으로 대조구(23.2 kg), 부식토 처리구(23.1 kg), 비타민 C 처리구(23.4 kg)와 비슷하여 수치적으로 증가하였다. 대조구와 처리구별 시험 시작 전 유성분(유지방, 유단백, 유당, MUN 및 SNF) 및 체세포 수의 변화는 일부 유의성이 인정되었다(p<0.05). 4주간의 시험 기간 중 전반기(1~2주)와 후반기(3~4주)의 유성분 변화를 보면 부식토 첨가구에 있어서 유단백질과 SNF가 유의적으로 증가하는 경향을 나타내었다. 대조구와 처리구의 시험 시작 전 의 혈액내 영양성분 (총단백질, 콜레스테롤, NEFA, BUN), 간기능 성분(AST, GGT) 및 무기물(Ca, P, Mg)에서 뚜렷한 변화를 나타내지 않았다. 이상의 결과를 종합해 볼 때 착유우에 부식토를 급여하는 것이 유성분, 체세포 수 및 생리적으로 긍정적인 영향을 줄 것으로 판단된다.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.427-431
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• 2002

Alkali treatment following acidic hydrolysis (ATAH) is a commonly used practice for reducing the levels of monochloropropanediol in commercial Korean soy sauce. This study investigated the chemical compounds produced in commercial Korean soy sauce made by ATAB. The levels of amino-N, total acidity, pH, salinity and Brix of the soy sauce were 6.66%, 2.52%, 19.81%, 4.57 and 35.01, respectively. The major fatty acids were C18:2n-6, C16:0, Cl8:ln-9 and C18:3n-6. The concentration of polyunsaturated fatty acids were especially high, with of C18:2n-6 (49.8%) being the highest followed by C18:3n-6 (3.8%) and C18:3n-3 (2.4%) in that order. Among the non-volatile organic acids, the concentration of levulinic acid (1,206.28 mg/100 g) was the highest, while the taste value of citric acid was the highest. Among the ATP related compounds, IMP concentration (31.19 mg/100 g) was highest followed by AMP, hypoxanthine and GMP in that order. The concentrations of free and total amino acids in soy sauce were 6,136.94 mg/100 g and 8,702.76 mg/100 g, respectively. On the other hand, the taste value of glutamic acid, a major amino acid flavor determinant in soy sauce, was highest of all the amino acids, which is desirable since most free amino acids such as methionine, histidine and phenylalanine have a bitter taste that detracts from the flavor of soy sauce.

• 한국가금학회지
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• 제33권1호
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• pp.1-6
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• 2006

본 연구는 육계에 오메가 3계열을 다량 함유한 정어리유 1%와 쑥의 급여수준(0, 1, 2, 4%)에 따라 4처리구로(T1, T2, T3, T4)구분하여 5주간 급여 후 도계하여 대퇴 부위 근육을 냉장온도$(4{\pm}1^{\circ}C)$에서 10일간 저장하면서 pH, VBN, TBARS 및 육색의 변화를 조사하였다. 증체량은 T3구에서 가장 낮았으며, pH는 대조구에 비하여 처리구에서 높았고, 저장 기간이 경과하면서 유의성 있게 상승하였다(P<0.05). VBN과 TBARS는 처리구에서 저장기간이 지남에 따라 증가하였을지라도 대조구는 처리구에 비하여 높은 경향을 나타내었다. 육색은 처리구에서 $L^*$과 $b^*$값이 대조구보다 높은 경향이었다. 이상의 실험 결과로 미루어 육계사료에서 정어리유를 1%급여시에 2%까지 첨가하면 계육의 품질 및 저장성 개선 효과가 있는 것으로 사료된다.

• 한국축산식품학회지
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• 제31권3호
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• pp.428-435
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• 2011

This study was conducted to investigate the effect of immersion treatment using lactic acid (LA) and sodium benzoate (SB) on the physicochemical quality and freshness of spent hen breast meats. A total of 135 spent hen breast meats were subjected to 9 different treatments using various concentrations of LA and/or SB in sterile DW. The 9 treatment groups were as follows: Control, sterile DW without LA or SB; T1, 1% LA; T2, 2% LA; T3, 4% LA; T4, 1% LA and 0.1% SB; T5, 2% LA and 0.1% SB; T6 2% LA and 0.2% SB; T7, 2% LA and 0.4% SB; T8, 4% LA and 0.2% SB, respectively. All groups were kept at 4oC for 15 d. The microbial counts in the control group gradually increased during storage, but those for the treated groups were significantly lower than the control or were not detected. The pH values of the control were significantly higher than those of the treated groups (p<0.05). In the color measurements, the lightness ($L^*$) and yellowness ($b^*$) values increased during storage and the redness ($a^*$) values decreased (p<0.05). The K-value and volatile basic nitrogen of the treated groups were significantly lower than those of the control group (p<0.05). Overall, the combined results of this study indicate that LA and SB could be used as favorable preservatives for spent hen breast meats to extend their shelf-life during refrigerated storage.

• 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.

• 한국식품저장유통학회지
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• 제30권3호
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• pp.369-382
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• 2023

We examined the changes in the physicochemical quality characteristics and antioxidant activity of fresh-cut Fuji apples (Malus pumila) during processing and storage after treatment with browning inhibitors. The primary aim was to elucidate processing suitability and storability. We observed that in the processing stage of slicing fresh Fuji apples, there were no significant differences in 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging ability and ferric-reducing antioxidant power (FRAP). However, after NaClO treatment, total flavonoid and total polyphenol contents decreased. When freshcut Fuji apples were treated with browning inhibitors and stored at 4℃, the L value and hardness decreased; however, the weight loss rate increased based on the storage period of all fruit groups treated with Citrus unshiu Markovich (CuM), calcium ascorbate (CA), and ascorbic acid (AA). The pH increased after 2 days of storage in 1% CuM and after 6 days of storage in 1% CA; however, no changes in pH were observed during the storage period in 1% AA. The DPPH radical scavenging activity was generally good under storage conditions of 1% AA at 4℃ and 1% CA at 20℃. Furthermore, FRAP remained relatively constant under storage conditions of 1% CA. The quality characteristics and antioxidant activity of fresh-cut fruits during processing and storage can be used as basic data for industries. Furthermore, we can gain confidence in quality improvements by improving the production and distribution environment of fresh-cut agricultural products.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.812-824
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• 2020

Objective: The aim of this work was to assess the effect of fermented blueberry (FB; 2%, 4%, and 6%) on the oxidative stability and volatile molecule profiles of emulsion-type sausage stored at 4℃ for 28 days. Methods: The antioxidant activity of FB was determined through radical-scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. Four formulations of sausage treatments with different FB levels (0%, 2%, 4%, 6%) were prepared, then peroxide value (POVs), thiobarbituric acid-reactive substances (TBARS) values, protein carbonyls and thiol groups were measured. The aroma profiles of sausages for each treatment was also determined. Results: The half maximal inhibitory concentration indicated that FB had greater scavenging ability than ascorbic acid against DPPH and hydroxyl radicals. Sausages with FB significantly retarded increases in POVs and TBARS, as well as in the content of protein carbonyls during all storage days (p<0.05). Particularly, 4% and 6% FB-treated sausages had better oxidation inhibition effects. However, FB accelerated the reduction in thiol groups (p<0.05). Additionally, FB inhibits the excessive formation of aldehyde compounds; for example, hexanal, which may cause rancid flavors, decreased from 58.25% to 19.41%. FB also created 6 alcohols (i.e., 2-methyl-1-propanol, 3-methyl-1-butanol, and phenylethyl alcohol), 5 ester compounds (i.e., ethyl acetate, ethyl lactate, and ethyl hexanoate) and 3-hydroxy-2-butanone in the sausages that contribute to sausage flavors. The principal component analysis showed that the aroma profiles of sausages with and without FB are easily identified. Conclusion: The addition of FB could significantly reduce the lipid and protein oxidation and improve oxidative stability for storage. Also, adding FB could inhibit rancid flavors and contribute to sausage flavors.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2012년도 춘계학술논문집 1부
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• pp.452-454
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• 2012

본 논문에서는 열분해 및 촉매반응의 의한 Hydrazine의 Ammonia 전환율을 연구하였다. 원자력발전소 2차 계통은 물/증기 순환계통으로 기기 및 배관의 부식을 억제하고, 증기발생기(Steam Generator, SG)의 부식생성물 유입을 최소하기 위해 전휘발성처리법(All Volatile Treatment, AVT)을 적용하여 계통수의 pH를 약염기성으로 유지하고 있다. 또한 Hydrazine을 이용하여 계통수의 용존산소제거 및 환원성 분위기를 유지하고 있다. 현재 사용되는 AVT는 대부분 단일 아민(Ammine)으로 계통 전 영역에서 pHt를 약염기성으로 유지하기 어렵다. 따라서 복합 아민을 이용하여 단일 아민의 상호단점을 보완한 수처리법을 적용해야한다. 하지만 복합 아민을 적용할 경우 추가 아민 주입설비, 설치부지, 시설유지보수 및 관리가 요구되므로 기존 주입약품을 이용하여 아민을 공급할 수 있는 연구가 필요하다. 따라서 본 연구에서는 Hydrazine의 열분해 및 촉매반응을 이용한 Ammonia 전환율을 조사하였다.