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Shrimp residues were dried (65 °C), grounded, and posteriorly used as an ingredient to the production of ‘spiced shrimp flour’ and ‘shrimp flavoured biscuits’. Both products were packed in modified atmosphere (100% N2) and stored for 180 days (25 °C) for shelf life evaluation. The centesimal composition, physicochemical, microbiological and sensory analyses were carried out in triplicate. The microbiological analysis (residue and shrimp flour) was within the limits of the legislation, confirming the hygienic–sanitary care during processing. The protein content was the most outstanding (40.13% for the spiced shrimp flour and 20.52% for the shrimp flavoured biscuits). The microbiological evaluation for the ‘spiced shrimp flour’ and ‘shrimp flavoured biscuits’ was below the legal limit, and both products were accepted by sensory analysis. The shelf life evaluation demonstrated stability for 6 months. Thus, we concluded that the Litopenaeus vannamei shrimp residue is a promising ingredient in the food industry.  相似文献   
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A set of seven extraction experiments was performed to investigate the influence of pressure cycles on the kinetics of solute removal from leaves of mate dispersed in water. The mass ratio of liquid to dry solid (40), the temperature (32°C), and time of extraction (3600?s) were not varied. Five extraction runs were under cyclic pressurization (1?cycle?=?300?s at 91.4?kPa?+?300?s at 182.8?kPa) and stirring speeds (S) of 0, 150, 500, 1500, and 2000?rpm, while the two other ones were at constant pressure (182.8?kPa) and S close to 1500 and 2000?rpm. Based on seven pairs of parameters of a reliable second-order kinetic model (R2?≥?0.967), cyclic pressurization had no effect on equilibrium and kinetics of extraction (p?>?0.05) when the role of convection on solute transfer was negligible (S?≥?500?rpm). In the stirring speed range from 500 to 2000?rpm, the operation was controlled by diffusion (Bi >?1.7?×?103), so a transient two-dimensional diffusion model was able to describe correctly the changes of solute concentration with time. Below 500?rpm, solute transfer was governed by a combination of diffusion and convection with the external resistance to mass transfer as a function of S (16?≤?Bi?≤?28).  相似文献   
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Increasing efficiency of electrical equipment is essential to national energy rationality, enabling energy consumption reduction and postponing inversion in distribution, transmission and generation, as well as mitigating environmental impacts associated with such activities. Considering such purposes, two actions have been promoted in Brazil: (a) minimum energy performance standards (MEPS) have been required for some appliances and (b) consumers have been informed about the most efficient products by ??endorsement labeling.?? The purpose of this study is to assess window and split air-conditioners with Brazilian MEPS. To evaluate the impact of efficient air-conditioners in this market, a model was developed based on estimates for quantity of equipment in operation and unitary consumption, as determined by local temperature records. From this model, it was deduced that using only efficient conditioners (class A for Brazilian Labeling Program/INMETRO, with PROCEL Label) an annual saving of 322?GWh and a reduction in demand of 109?MW could be obtained in 2007. Furthermore, it was observed that the current MEPS established by Brazilian legislation for air-conditioners may be considered relatively low. Considering that MEPS are similar to those observed in China (the main exporter of air-conditioners to the Brazil), an energy saving of roughly 222?GWh could be achieved in the same year. Impacts on emission of greenhouse gases are also estimated.  相似文献   
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Polymer Bulletin - In this work, electrospun fibers of poly(butylene adipate-co-terephthalate) (PBAT) and poly(N-isopropylacrylamide) (PNIPAAm) blends, PBAT/PNIPAAm, with different mass ratios,...  相似文献   
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Food traceability is essential to preserve the identity of unique quality traits against frauds or commercial disputes. Therefore, there is a growing demand of new traceability systems for the collection of information related to units/batches of food ingredients and products.  相似文献   
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