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《Food Control》2016
The objective of this study was to determine the relationship between Salmonella levels (presence and numbers) in chicken spleens and in mechanically separated chicken (MSC) at a commercial processing plant. Composite spleen and MSC samples were collected from 18 flocks at a commercial poultry processing plant. A total of 180 samples of each type were collected and tested for Salmonella using the most probable number (MPN) and enrichment methods. Overall, Salmonella was detected in 15.6% and 27.8% of spleen and MSC samples, respectively. The mean log MPN was 0.95 and 0.85 for the spleen and MSC samples, respectively. There was a significant relationship between Salmonella presence in spleen and MSC samples. However, the log MPN numbers in MSC samples were not significantly related to those in spleen samples. Salmonella presence in composite spleen samples (an indication of systemic infection in chickens) may predict MSC contamination with this pathogen, at the flock level. 相似文献
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Effect of ammonia inhibition on microbial community dynamic and process functional resilience in mesophilic methane fermentation of chicken manure 下载免费PDF全文
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David Makarapong Supawan Tantayanon Chupun Gowanit Chaidate Inchaisri 《International Journal of Dairy Technology》2020,73(1):301-305
This study was conducted to investigate the effect of UV‐C irradiation on the reduction of microorganisms in raw milk. The experiments were carried out by varying the flow rates of 2, 4 and 7 L/min with 39W and 48W UV‐C. The number of microorganisms was reduced by 4.70 (39W) and 4.60 log10 CFU/mL (48W) at 120 min. With the residence time of 4.95 s and the UV‐C doses of 98 and 109.9 mJ/cm2 at 253.74 nm, the reduction of microorganism was clearly observed with no significant influence of different UV‐C power settings on the oxidation of milk fat. 相似文献
97.
S. Chantasiriwan 《Chemical Engineering Communications》2017,204(12):1466-1473
The evaporation process in raw sugar manufacturing consists of juice heater, multiple-effect evaporator, and crystallizer. Two performance parameters of the evaporation process are the rate of processed sugar juice and the steam economy, defined as the ratio between water content of sugar juice entering the process to the amount of steam required to run the process. If the total surface area of the multiple-effect evaporator is fixed, the performance parameters are affected by the distribution of the surface area among the effects of the evaporator. Although the optimization of evaporator surface area distribution has been investigated in previous studies, they have considered only the multiple-effect evaporator, and overlooked interactions between the three components of the evaporation process. The current investigation proposes a model of the evaporation process that takes into account interactions between the three components of the process through mass and energy balances. The model is used to find the optimum surface area distribution that maximizes the rate of sugar juice processed by the system and the optimum surface area distribution that maximizes the steam economy are different. 相似文献
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K. Mchiouer S. Bennani M. Meziane 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(24):3572-3577
In this study, a Lactobacillus strain was isolated from raw cow milk. It was tentatively identified at the species level according to its carbohydrate fermentation profile and phenotype characteristics as Lactobacillus paracasei KSNM. The susceptibility of the identified Lactobacillus to 23 antibiotics was performed using the disc diffusion testing method. Inhibition zone diameters were measured and expressed in terms of sensitive, intermediate or resistant. KSNM strain was sensitive toward; amoxicillin, ampicillin, amoxyclav (amoxicillin + clavulanic acid), tetracycline, macrolides, sulfamides/trimethoprim, and rifampicin. But, it expressed intermediate sensitivity toward; cefamandole, cefaclor, and cephalothin. However, it was resistant to penicillin G, aminoglycosides, quinolones, ciprofloxacin, lincomycin, nitroxolin, and a large number of cephalosporins, which included cefoxitin, cefotaxime, and ceftriaxone. 相似文献
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某水泥厂建厂时,在原料上料系统流程上采用了传统的机旁手动操作方式。几年来,手动操作控制逐渐显露出很多弊端,于是将手动按钮启停控制更换为机旁优先的自动控制方式。详细介绍了自动控制方式的实施方案和控制原理,系统改造后,画面友好、操作简单、控制灵活,改造效果良好。 相似文献