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101.
Inês Portugal Susana C. Ribeiro Ana M.R.B. Xavier Filipe Centeno Pierre Strehaiano 《International Journal of Food Science & Technology》2011,46(2):284-289
Maloalcoholic fermentation (MAF) of grape must by Schizosaccharomyces pombe immobilised in calcium‐alginate double‐layer beads (ProMalic®) was studied in Erlenmeyer flasks and in a total recycle fixed‐bed reactor operating in batch mode. The reaction is pseudo‐first order with respect to l ‐malic acid and under similar conditions deacidification is faster in the recycle reactor. This was attributed to mass transfer limitations which were confirmed in the recycle reactor by studying the influence of yeast load on the rate of MAF. Mass transfer limitations are also responsible for the lower activation energy of fermentation with the immobilised yeast (67 ± 9 kJ mol?1) in comparison with the free cells (126 ± 19 kJ mol?1). Alcoholic fermentation and MAF were performed simultaneously, both in the recycle reactor and in the industrial trials, confirming the efficacy of immobilised S. pombe to reduce grape must acidity without interfering with the main fermentation. Altogether, the present results are useful for the scale‐up of a recycle reactor to process large volumes of grape must. 相似文献
102.
建立了流动注射(FI)在线编结反应器(KR)预富集与火焰原子吸收光谱(FAAS)联用测定水样中痕量镍的吸力洗脱方法。洗脱过程依靠蠕动泵的吸力而不是推力实现洗脱剂的输送,明显降低了被分析物在洗脱过程中的分散,提高了原子吸收信号峰值(A)和浓集系数(EF)。增加了样品溶液排空步骤,保证了每次实验的准确性和重复性。进样流速6.0 mL/min,进样时间60 s,测定水样中的镍,EF由传统洗脱法的4.9提高到9.8,检出限为3.1μg/L,测样频率为41 h-1,相对标准偏差(RSD,n=11)为2.2%,以体积分数0.01%的三乙醇胺(TEA)为掩蔽剂,在水样中的回收率为95.5%~97.8%。 相似文献
103.
Ana‐Paola Echavarría Albert Ibarz Josep Conde Carles Torras Jordi Pagán 《International Journal of Food Science & Technology》2012,47(1):47-52
The aim of this paper, in which clogging occurs on the filter at a constant vacuum pressure and constant pectin weight, is to find the optimal values of the variables, temperature and time, to know the best conditions to reduce this clogging by enzymatic hydrolysis. Moreover, different properties of the compression of the cake in the filter were determined such as the filtering medium total resistance (RfT), bed porosity (ε) and the cake‐specific resistance (α) at different times and temperatures. The filter area was 0.142 m2, and the value of the mass fraction of solids in the filtered suspension (S) was 0.12. Scanning electron microsopy (SEM) analyses were performed. The results showed that the compressive stress corresponding to the cake improves the flow rate in the filtration flux at the optimal temperature and time for the process, where the enzyme reaches its highest activity. The test results of this study can be applied in different system of filters during cross‐flow filtration. 相似文献
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Tomáš Brányik António A. Vicente Pavel Dostálek José A. Teixeira 《Journal of the Institute of Brewing》2008,114(1):3-13
The attractive prospect of a continuous beer fermentation system consists mostly of the accelerated transformation of wort into beer. Although continuous beer fermentation has been studied as a promising technology for several decades, the number of industrial applications is still limited. The major obstacle hindering the extensive industrial exploitation of this technology is the difficulty in achieving the correct balance of sensory compounds in the short time typical for continuous systems. This paper offers an integral view on the particularities of continuous systems, which may impart beer a sensorial character distinct from conventionally fermented counterparts. The main groups of flavour active compounds are discussed from the perspective of possible control strategies by means of process parameters and strain selection. 相似文献
107.
IC反应器处理马铃薯淀粉生产废水的试验研究 总被引:4,自引:3,他引:4
试验采用超滤-IC反应器-MBR工艺处理马铃薯淀粉生产废水,重点研究了IC反应器处理马铃薯淀粉废水的工艺参数。结果表明,在常温下,当进水COD的质量浓度为6000~9000mg/L、HRT为5h、容积负荷为23.62kg[COD]/(m3·d)时,IC反应器对COD的去除率为91.43%。采用该工艺处理马铃薯淀粉生产废水完全可以达到废水回用的目的。 相似文献
108.
厌氧序批式反应器是第三代新型高速厌氧反应器,其快速启动运行规律的研究相对较少。总结了目前国内外关于ASBR快速启动的研究进展情况,并结合试验成果,论述了ASBR快速启动的影响因素,包括运行方式、搅拌、种泥类型、投加物、反应器构型等方面,以及当前研究中存在的问题。 相似文献
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