• 제목/요약/키워드: physicochemical quality

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호소 퇴적물 내부생산성 오염도 영향 평가 및 용출특성에 관한 연구 (The evaluation of pollution level and release characteristics by inner productivity in the sediment of lake)

  • 이상은;최이송;이상근;이인호;오종민
    • 환경영향평가
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    • 제21권1호
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    • pp.81-91
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    • 2012
  • In this study, it is grasped the status of nutrients through an investigation of release characteristics and physicochemical properties of sediments on reservoir. And then the effect of sediments is evaluated on the water quality in reservoir. In the results of physicochemical analysis, the pollution level of midstream is the highest, which shows the traits that the water is more deeper and takes place a deposition consistently. Then, the pollution level of upstream is higher than downstream's because inflow has influence on the upstream directly. The downstream is located near tidal gate so that the soil particles can be moved easily and are difficult to be deposited due to the distribution of seawater by control of tidal gate. Therefore, the downstream is showed the lowest pollution level than the others. Also, the concentration of SOD(Sediment Oxygen Demand) in the upstream which is influenced on the effect of inflow is highest than the others. When it analyzes under anaerobic and aerobic condition to understand the release characteristic of sediment, it shows that the release rate is low or negative under the aerobic condition. Whereas the release rate is usually positive under the unaerobic condition relatively. According to these results, it is necessary to maintain the proper environmental factors of water body for decreasing the release rate of sediment. Because the release rate is changeable under the different condition of water body. Therefore, proper strategies are required for increasing the self-purification of water as well as keeping the aerobic condition of sediment and managing a sediment layer directly to control the inner-pollution by the sediment of reservoir.

단체급식 및 외식업체에서 이용되는 양상추의 식초수 소독의 적용을 위한 연구;이화학적 특성 및 관능적 특성 분석을 중심으로 (Applying Vinegar as a Disinfectant for Lettuce in Foodservice Operations;A Focused Evaluation of Its Physiological and Sensory Characteristics Effects)

  • 김혜영;김현정
    • 한국식품조리과학회지
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    • 제24권2호
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    • pp.228-235
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    • 2008
  • In this study, vinegar disinfection was evaluated as a novel method for the preparation of raw food ingredients used in foodservice operations. The test materials were washed and disinfected using three different methods, and were then stored at temperatures of $3^{\circ}C\;and\;10^{\circ}$ for 7 days; Following storage, physicochemical and sensory characteristic comparisons were performed. Temperature for all test materials ranged between 15.2-20. $9^{\circ}C$, water activity was maintained near 0.96, and the pH levels of the samples were 6.44, 6.29, and 6.35, respectively. Residual chlorine levels were generally low, ranging between 0.01 and 0.02. The physicochemical qualities of the samples were evaluated according to the storage method and temperature. Brightness(L value), redness(a value), and yellowness(b value) tended to increase with increasing storage time. The evaluated sensory characteristics included appearance, color, smell, taste, texture, and overall acceptance. With regard to storage temperature the vinegar-treated samples were evaluated as superior, receiving a score of 7.00, and the ingredients stored at $3^{\circ}C$ were evaluated as significantly (p< 0.001) superior to those stored at $10^{\circ}C$. Overall, vinegar is an effective disinfectant to apply in the preparation of raw vegetables that are typically served without heating, and which can cause serious food safety issues when contaminated.

팽화밀을 이용한 고추장 및 된장의 숙성중 이화학적 특성 (Changes in Physicochemical Properties of Kochujang and Doenjang Prepared with Extrudated Wheat Flour during Fermentation)

  • 금준석;한억
    • 한국식품영양과학회지
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    • 제26권4호
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    • pp.601-605
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    • 1997
  • 팽화밀을 이용한 고추장 및 된장의 숙성기간 중 품질 특성을 검토한 결과 수분 함량 및 조단백질의 변화는 숙성 기간 및 전분질 원료에 따라 큰 변화는 없었다. 염도 및 pH는 숙성기간 중 각 원료 공히 감소하는 경향을 나타내었고(호화밀쌀의 경우 pH는 고추장에서 5.1 에서 4.7, 된장에서는 5.4에서 5.0로 감소) 산도는 증가 하였다(호화밀쌀의 경우 고추장에서 8.7에서 9.1, 된장에서는 11.0에서 11.3로 증가). 숙성도(아미노태 질소) 및 색도는 감소하는 경향을 나타내었고 호화밀쌀의 경우 a값에서 고추장 및 된장 숙성 후(30일) 각각 5.9 및 5.3으로 가장 높았다. 팽화밀을 이용한 고추장 및 된장의 제조 후 품질 특성은 다른 원료와 큰 차이를 보이지 않아 앞으로 팽화밀의 이용 가능성을 보여 주었다.

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당 저감화 녹차 쿠키의 이화학적 감각적 품질특성 (Physicochemical and Sensory Characteristics of Sugar-Reduced Green Tea Cookies)

  • 최예진;김혜영
    • 한국식생활문화학회지
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    • 제36권2호
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    • pp.218-225
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    • 2021
  • The quality characteristics of sugar-reduced green tea cookies were tested, and there was no significant differences in density, spreadability, loss rate, and pH in all experimental groups (p<0.05). The sugar content of the sample with 100% sugar replaced was 0.96°Brix, which was significantly higher than the 0.80 °Brix of the control (p<0.05). The sample with 75% sugar substituted was 0.76°Brix, which was similar to that of the control (p>0.05). The calories per 100 g of cookies were reduced from 482 to 433 kcal in the sample groups, where the sugar content was reduced from 0 to 100%. Carbohydrates also decreased with decreasing sugar content. The protein was 5g in the sugar sample group reduced by 0-25%, and 6 g in the sugar sample group reduced by more than 50%. Dietary fiber was three times higher in the sugar sample group reduced by 75% than the control, and four times higher in the sugar sample group reduced by 100% than the control. No significant differences in the sweet sensory intensities were observed between the control and the 75% reduced sugar sample group (p>0.05). The brightness, savory, sweet, and aftertastes were similar in all experimental groups (p>0.05). Overall, high value-added green tea cookies with a more than 75% reduction in sugar were successfully developed with added functions of immunity, anti-cancer, antioxidant functions, preventing constipation and obesity, without deteriorating the sensory and physicochemical qualities tested.

오미자 열매 추출액을 첨가한 식혜의 품질특성 (Quality of Sikhe Incorporated with Hot Water Extract of Omija (Schisandra chinensis Baillon) Fruit)

  • 이준호
    • 산업식품공학
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    • 제15권1호
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    • pp.80-84
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    • 2011
  • 오미자 열매 추출물의 첨가량을 0-50%로 달리하여 식혜를 제조한 후 물리화학적 및 관능적 품질특성을 측정하고 각 특성사이의 상관관계를 살펴보았다. 추출물의 첨가량이 증가함에 따라 식혜의 pH는 유의적으로 감소한 반면 가용성 고형분 함량 및 적색도 ($a^*$값)는 증가하였다(p<0.05). 한편, 밝기를 나타내는 $L^*$값과 황색도를 나타내는 $b^*$값은 추출물의 첨가량과 직접적인 관계를 나타나지 않았다. 관능적 품질특성 중 색, 신맛, 단맛은 추출물의 첨가량과 유의적인 관계를 나타내었다(p<0.05). 상관분석 결과 추출물의 첨가량은 $L^*$값과 $a^*$값을 제외한 모든 물리적 및 관능품질 특성과 유의적인 관계를 나타내었다. 소비자 기호도검사에 의하면 10% 오미자 열매 추출물을 첨가한 식혜의 전체적인 기호도가 다른 시료군에 비해 유의적으로 높음을 알 수 있었다(p<0.05).

Physicochemical attributes, oxidative stability, and microbial profile of boneless sirloin and bone-in T-bone steaks from Hanwoo steer with reference to dry-aging

  • Ali, Mahabbat;Nam, Ki-Chang
    • Journal of Animal Science and Technology
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    • 제63권5호
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    • pp.1169-1181
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    • 2021
  • We investigated the comparative physicochemical attributes, oxidative stability, and microbial characteristics of 28 days dry-aged meat in between boneless sirloin (gluteus medius) and bone-in T-bone steaks (infraspinatus) muscles from Korean Native Hanwoo Steer (KNHS). Results reveal that regardless of the muscles, dry-aging increased protein content and water-holding capacity (WHC) (p < 0.05). Meat from infraspinatus-aged muscle led to darker meat with higher pH values than un-aged meat (p < 0.05). However, fat content, CIE a*, and CIE b* remained unchanged in both muscles at aging. At aged meat, thiobarbituric acid reactive substances (TBARS) values from bone-in infraspinatus muscle was 2.5-fold higher than boneless gluteus medius muscle (p < 0.05). Dry-aging led to an increase in the contents of total unsaturated fatty acids (UFAs), monounsaturated fatty acids (MUFAs), and UFA/saturated fatty acids (SFA) in both muscles (p < 0.05). Furthermore, gluteus medius aged muscle concentrated with olic acid (C18:1) compared to infraspinatus aged muscle. Irrespective of the muscles, dry-aging enhanced the total free amino acids (FAAs) as well as tasty, and bitter amino acid contents whereas decreased the tasty/bitter amino acids (p < 0.05). Aromatic amino acid, tryptophan that converted to serotonin was 2-fold higher in boneless gluteus medius muscle than bone-in infraspinatus muscle at pre and post aging processes (p < 0.05). Aged Infraspinatus muscle increased total bacteria (p < 0.05) while no salmonella spp. was detected in both muscles. Taken together, our study confirms that 28 days dry-aging profiling the quality characteristics of boneless sirloin (gluteus medius) and bone-in T-bone steaks (infraspinatus) distinctly while gluteus medius aged steak performs better owing to oxidative stability and functional compounds than infraspinatus aged steak.

Responses of Soil Rare and Abundant Sub-Communities and Physicochemical Properties after Application of Different Chinese Herb Residue Soil Amendments

  • Chang, Fan;Jia, Fengan;Guan, Min;Jia, Qingan;Sun, Yan;Li, Zhi
    • Journal of Microbiology and Biotechnology
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    • 제32권5호
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    • pp.564-574
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    • 2022
  • Microbial diversity in the soil is responsive to changes in soil composition. However, the impact of soil amendments on the diversity and structure of rare and abundant sub-communities in agricultural systems is poorly understood. We investigated the effects of different Chinese herb residue (CHR) soil amendments and cropping systems on bacterial rare and abundant sub-communities. Our results showed that the bacterial diversity and structure of these sub-communities in soil had a specific distribution under the application of different soil amendments. The CHR soil amendments with high nitrogen and organic matter additives significantly increased the relative abundance and stability of rare taxa, which increased the structural and functional redundancy of soil bacterial communities. Rare and abundant sub-communities also showed different preferences in terms of bacterial community composition, as the former was enriched with Bacteroidetes while the latter had more Alphaproteobacteria and Betaproteobacteria. All applications of soil amendments significantly improved soil quality of newly created farmlands in whole maize cropping system. Rare sub-communitiy genera Niastella and Ohtaekwangia were enriched during the maize cropping process, and Nitrososphaera was enriched under the application of simple amendment group soil. Thus, Chinese medicine residue soil amendments with appropriate additives could affect soil rare and abundant sub-communities and enhance physicochemical properties. These findings suggest that applying soil composite amendments based on CHR in the field could improve soil microbial diversity, microbial redundancy, and soil fertility for sustainable agriculture on the Loess Plateau.

미선나무 잎 추출물을 이용한 음료 개발 및 이화학적 특성 (Beverage Development using Abeliophyllum distichum Leaf Extract and Its Physicochemical Properties)

  • 이호진;권순영;정필문;김은아;이경행
    • 한국식품영양학회지
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    • 제36권2호
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    • pp.122-128
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    • 2023
  • A beverage was developed using the Abeliophyllum distichum leaf (AL). The beverage was prepared by adding it to apple juice by concentration, and physicochemical quality, antioxidant activities, and sensory evaluation were measured. Soluble solid and reducing sugar content of the control were 12.57 °Brix and 11.40%, respectively, and there was no difference from the group with addition of the AL extract. However, pH was slightly increased upon addition of AL extract. Lightness and yellowness increased when AL extract was added. Verbascoside content was not detected in the control, but it increased as the concentration of AL extract increased. The contents of ascorbic acid and flavonoids were 5.38 and 20.42 mg%, respectively, and there was no significant difference between the groups. However, the content of polyphenols increased as the concentration of the AL extract increased. DPPH radical and metal ion scavenging activity were increased by addition of the AL extract, but there was no difference in the ABTS radical scavenging activity. As a result of the sensory evaluation, there was no difference from the control even wihen the AL extract was added; thus, it was considered that there was no problem with the degree of acceptability when added within about 300 ppm.

Evaluation of the physicochemical, metabolomic, and sensory characteristics of Chikso and Hanwoo beef during wet aging

  • Dongheon Lee;Hye-Jin Kim;Azfar Ismail;Sung-Su Kim;Dong-Gyun Yim;Cheorun Jo
    • Animal Bioscience
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    • 제36권7호
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    • pp.1101-1119
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    • 2023
  • Objective: This study aimed to evaluate the physicochemical, metabolomic, and sensory qualities of Chikso and Hanwoo beef during 28 days of wet aging. Methods: Rump and loins from Hanwoo and Chikso were obtained and wet-aged for 28 days at 4℃. The samples were collected at 7-day interval (n = 3 for each period). Physicochemical qualities including pH, meat color, shear force value, and myofibrillar fragmentation index, metabolomic profiles, and sensory attributes (volatile organic compounds and relative taste intensities) were measured. Results: Chikso showed a significantly higher shear force value than Hanwoo on day 0; however, no differences between breeds were found after day 14, regardless of the cuts. Overall, Chikso had more abundant metabolites than Hanwoo, especially L-carnitine and tyrosine. Among the volatiles, the ketone ratio was higher in the Chikso rump than the Hanwoo rump; however, Chikso had fewer alcohols and aldehydes than Hanwoo. Chikso rump showed higher taste intensities than the Hanwoo rump on day 0, and sourness decreased in Chikso, but increased in the Hanwoo rump on day 14. Wet aging for 14 days intensified the taste of Chikso loin but reduced the umami intensity of Hanwoo loin. Conclusion: Chikso had different metabolomic and sensory characteristics compared to Hanwoo cattle, and 14 days of wet aging could improve its tenderness and flavor traits.

쇠고기죽 제조 시 쌀입자 크기가 죽의 품질에 미치는 영향 (Effect of Grain Size on the Physicochemical & Nutritional Properties of Beef Porridge)

  • 김혜란;김민지;양윤형;이근종;김미리
    • 한국식생활문화학회지
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    • 제25권1호
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    • pp.70-75
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    • 2010
  • The object of this study was to investigate the effects of rice particle size on the physicochemical properties of beef-rice porridge. The pH of beef-rice porridge was decreased as compared to that of the control, while the redness of beef porridge increased according to rice particle size. The viscosity of flour in the beef-rice porridge was the highest among three porridges, at $40^{\circ}C$. The protein content of beef-rice porridge was increased 3-fold over that of rice porridges. The total amino acid content of the beef-rice porridge was 3071.2 mg/100 g, and that of rice porridge was 1147.5 mg/100 g. As compared to rice porridge, the maximum amounts of the amino acids Lys and Thr were increased beef-rice porridge. Sensory evaluation results showed that the beef-rice porridge with a particle size half that of rice had the highest scores in color, taste, texture, and overall preference. Based on these results, it is suggested that beef-rice porridge with a particle size half (0.7-2.5 mm) that of rice has optimal quality in terms of both physicochemical and sensory properties.