• Title/Summary/Keyword: SCFA production rate

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Effect of Loading Rate on Acidogenic Fermentation of Domestic Waste Sludge (산발효에 있어서 하수슬러지의 유입부하율의 영향)

  • Eom, Tae-Kyu;Han, Dong-Yueb
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.1
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    • pp.15-21
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    • 2004
  • The purpose of this research was to investigate loading rate of influent for acidogenic fermentation. Laboratory batch experiments were conducted, at $35^{\circ}C$, HRT 18hr, pH 6 and used 3.5L reactor. Loading rate of influent was varied 2.0 to 4.0g VSS/L, TOA concentration is decreased according to increasing loading rate Over 2.5g VSS/L. When loading rate is 2.0g VSS/L, hydrolysis percentage show the maximum value of 87%. Most of SCFA is consist of HAc, HPr, I-HBu and MBu. HAc concentration is 5,233mg/L in the 2.0g VSS/L condition. So, for this study, we think that limiting loading rate is 2.5g VSS/L. SCFA species was investigated to HAc, HPr, I-HBu and n-HBu during our studying. HAc/SCFA ratio is about 89.3%, SCFA production rate is highest to $1,104mg\;COD/L/d{\cdot}gPCOD$ for 2.0g VSS/L loading rate.

Flavor Compounds of Cholesterol-Reduced Cheddar Cheese Slurries

  • Kwak, H.S.;Chung, C.S.;Ahn, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.1
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    • pp.117-123
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    • 2002
  • This study was carried out to find the difference in flavor compounds between cholesterol-reduced Cheddar cheese slurries and control sample. The cheeses were made by 3 different treatments as followings: 1) Control (no homogenization, no ${\beta}$-CD), 2) Trt A (1,000 psi milk homogenization, 1% ${\beta}$-CD) and 3) Trt B (cream separation following by 10% ${\beta}$-CD, mixed with skim milk at 1,000 psi homogenization). The cholesterol removals of the cheeses were 79.30% (Trt A) and 91.22% (Trt B). The cheese slurries made by the cheeses were aged at $32^{\circ}C$ for 3 wk. The production of short-chain fatty acids (SCFA) was significantly increased with storage time in all treatments. Total amount of SCFA was dramatically increased at 2 wk and maintained thereafter in control group. The amounts of acetone and acetaldehyde were slightly increased in control at 3 wk, however, no difference was found in others. Ethanol production was dramatically increased at 1 wk and decreased thereafter in all treatments. Based on our results, cheese slurries for Trt B showed a highest cholesterol removal rate. Although little difference was found in flavor production, lower amount of SCFA was found in Trts A and B in 2 and 3 wk. It may indicate that a certain amount of SCFA is decreased during ${\beta}$-CD treatment.

Effect of supplementation of yeast with bacteriocin and Lactobacillus culture on growth performance, cecal fermentation, microbiota composition, and blood characteristics in broiler chickens

  • Chen, C.Y.;Chen, S.W.;Wang, H.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.2
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    • pp.211-220
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    • 2017
  • Objective: The aim of the present study was to investigate the effect of yeast with bacteriocin and Lactobacillus cultures (mixture of Lactobacillus agilis BCRC 10436 and Lactobacillus reuteri BCRC 17476) supplements, alone or in combination, on broiler chicken performance. Methods: A total of 300, 1-d-old healthy broiler chickens were randomly divided into five treatment groups: i) basal diet (control), ii) basal diet+0.25% yeast (Saccharomyces cerevisiae) (YC), iii) basal diet+0.25% yeast with bacteriocin (BA), iv) basal diet+Lactobacillus cultures (LAB), and v) basal diet +0.25% yeast with bacteriocin+Lactobacillus cultures (BA+LAB). Growth performance, cecal microbiota, cecal fermentation products, and blood biochemistry parameters were determined when chickens were 21 and 35 d old. Results: The supplementation of YC, BA, and BA+LAB resulted in a significantly better feed conversion rate (FCR) than that of the control group during 1 to 21 d (p<0.05). The LAB supplementation had a significant effect on the presence of Lactobacillus in the ceca at 35 d. None of the supplements had an effect on relative numbers of L. agilis and L. reuter at 21 d, but the BA supplementation resulted in the decrease of both Lactobacillus strains at 35 d. The BA+LAB supplementation resulted in higher short chain fatty acid (SCFA) in the ceca, but LAB supplementation significantly decreased the SCFA at 35 d (p<0.05). All treatments tended to decrease ammonia concentration in the ceca at 21 d, especially in the LAB treatment group. The BA supplementation alone decreased the triacylglycerol (TG) concentration significantly at 21 d (p<0.05), but the synergistic effect of BA and LAB supplementation was required to reduce the TG concentration at 35 d. The YC supplementation tended to increase the plasma cholesterol at 21 d and 35 d. However, the BA supplementation significantly decreased the cholesterol and low density lipoprotein cholesterol level at 35 d. In conclusion, the BA+LAB supplementation was beneficial to body weight gain and FCR of broiler chickens. Conclusion: The effect of BA and LAB supplementation may be a result of the growth of lactic acid bacteria enhancement and physiological characterization of bacteriocin, and it suggests that the BA and LAB supplementation level or Lactobacillus strain selection should be integrated in future supplementation designs.