186,166 research outputs found
Dough buoyancy to monitor bread production process
No full textAn instrument able to record the buoyancy values of dough sample has been set up and used to test different recipes. Data of buoyancy versus time has been plotted and a curve with four typical sections identified. Each section gives some information about the influence of flour and microorganism on dough characteristic. The analysis of these curves allows an overview on the bread producing process with particular regards on mixing and proofing effects and could be used to compare different baking features
Variazione dei polifenoli e delle caratteristiche fisiche delle paste durante il processo di estrazione dell’olio di oliva
No full textA new method for Espresso Coffee brewing: Caffè Firenze
No full textEspresso coffee is the most popular choice for Italian coffee consumers. It has been estimated that every day, in the world, over of 50 million of Espresso cups are taken. As a consequence of this success, a large number of devices to make Espresso have been developed. In this scenario, a new device has been recently developed and patented (Eu. Patent 06 023 798.9; US 2010/0034942 A1). This brew method, named “Caffè Firenze”, uses a sealed extraction chamber, where water and gas provides pressure higher than the other extraction methods. Three main parts compose the apparatus: the gas source, the extraction chamber and the heat exchanger. The gas source provides the pressured gas required to raise the pressure of the system. The extraction chamber is made with chrome-brass and accessorized with two heating glow plugs. Many are the factors affecting Espresso quality: it is known that, coffee type, roasting conditions and degree, grinding and storage strongly affect the obtained brew. Also, several studies have been carried out on the effect of the setting parameters on quality, for example water pressure, water temperature, and brew time. Among the characteristics that determine Espresso quality, the main attribute for the visual analysis is, without doubts, the foam, also called “crema”. Indeed, height, aspect, and persistency of foam are features much appreciates by consumers. Two distinguish Espresso foam parameters are the persistency and foam index. Equipping a commercial bar machine with the new designed extraction chamber makes feasible the comparison between the traditional way to brew Espresso and the new device. The comparison was made holding the previous mentioned conditions, and differences were evaluated in terms of physical parameters and aromatic profiles. Caffè Firenze shows pronounced differences compared with traditional Espresso in term of foam-related parameters. Also, the new extraction device produces coffees with higher values of body-related parameters, such density and viscosity. The two kinds of Espressos are perceived different at visual analysis and taste by a panel test
Energetic and economic viability of olive stone recovery as a renewable energy source: A Southern Italy case study
No full textThe recovery of olive stone for biofuel purpose is becoming increasingly widespread in olive milling plants. The study looks at the economic and energetic benefits of using a de-stoner machine in a smallto- medium sized oil milling plant. The performance of the olive stone recovery system was evaluated over a full olive oil production season. The energetic viability of the de-stoner was assessed using an energy balance. The break-even point was achieved when about 76 tons of olives had been processed, which is less than the annual production of the mill under study. Similarly, in economic terms, the machine covered its costs after about the half of its technical life
Sustainability of sunflower cultivation for biodiesel production in Tuscany within the EU Renewable Energy Directive
No full textThe European Union Renewable Energy Directive 2009/28/EC (RED) has adopted climate change assessment as one of the environmental criteria used to evaluate the level of sustainability by indicating the impact values for every phase of the biofuel chain. This paper shows the results of a Life Cycle Assessment (LCA) of greenhouse gas (GHG) emissions from cultivation of sunflower for biodiesel production in Tuscany, Italy. In the five case studies, the GHG emissions of sunflower cultivation exceed the default value (18 g [CO 2eq] MJ -1) indicated by the RED. This is mainly due to diesel consumption and emissions from nitrogen fertilisers that are on average 180% and 255% higher than the reference values, respectively. GHG emissions allocation among sunflower biodiesel and co-products was made according to energy content principle. Only the biodiesel from sunflower cultivated in the two most efficient farms achieved a GHG saving with respect to conventional diesel (36%) that made it possible to fulfil the RED's requirements. From these results, it seems that the observance of such requirements on GHG emissions for sunflower biodiesel cultivation phase in Tuscany will not be easy to satisfy without a significant revision of local farm practices, aimed primarily at reducing the use of nitrogen fertilisers and diesel consumption. In fact, the GHG emissions reported in the RED for sunflower cultivation were calculated using excessively low farm inputs compared with the typical amounts for sunflower cultivation practices in Tuscan
A new espresso brewing method
No full textA new espresso brewing method has recently been developed. The main steps are: introduction and tamping of ground coffee in a sealed chamber, introduction of pressurized air into the chamber, the introduction of hot water and a pre-infusion phase. It is substantially different to the usual brewing method used in bars: the driving force for the flow is the pressure difference between the interior and the exterior of the chamber (rather than pressurized hot water provided by a motor-driven pump); the extraction process is partially static; the pressure is higher than the traditional method; and the temperature of the extraction chamber can be controlled (in addition to the water temperature control found in the traditional method). The method has been tested with three chamber temperatures and two pressures. At all settings, espressos produced using this method have particularly high and persistent foam. Furthermore, changes in pressure cause changes in some physical parameters and the amount of key odorants in the headspace above the coffee. A benchmark comparison with the capsule method gives differences in several aromatic compounds and in almost all the physical parameters. In conclusion, the beverage produced by the CF method is clearly recognizable by a thick and very persistent foam layer, while the method appears more flexible than the traditional one as the characteristics of the EC can be adjusted as a function of brewing conditions
Comparison of espresso coffee brewing techniques
No full textSeveral brewing techniques are used to make espresso coffee. Among them, the most widespread are bar machines and single-dose capsules, designed in large numbers because of their commercial popularity. As none of the current literature compares the effects of these different brewing techniques on espresso quality, this paper looks at two capsule methods and the traditional bar method. The methods were evaluated on the basis of the physico-chemical parameters and aromatic profile of nine espresso coffees prepared using the different techniques. Our results showed that with the same batch of roasted coffee, the same water and the same operative settings, the three different techniques can be distinguished by a principal component analysis. Furthermore, in terms of product reproducibility, the best results are provided by the two capsule systems. © 2013 Elsevier Ltd. All rights reserved
Comparison of grape harvesting and sorting methods on factors affecting the must quality
No full textThis study compared two harvesting techniques (manual and mechanical) and three grape sorting methods (no sorting, manual, and densimetric) in attempts to obtain high-quality must. The trials were carried out in 2009 and 2010 in Tuscany, Italy. The effectiveness of the harvest-sorting chain was assessed on two parameters. Substandard berries (SSB) is the percentage of berries, which do not meet quality standards that enter the winemaking process, and material other than grape (MOG) is a measure of the cleanliness of the berries entering the process. In the two years the trial was run the grape maturation level was widely different; in 2009 the vintage was more far mature than in 2010. With respect to SSB content and harvesting methods, in 2009 (more mature grapes) hand-picking reduced SSB content, while in 2010 there were no differences between the two harvesting methods. In both years, densimetric sorting reduced SSB content, while there were no significant differences between no sorting and manual sorting. In terms of MOG content, both harvesting and sorting results were inconsistent. In 2009, MOG was lower in mechanically harvested grapes; while in 2010 it was lower in hand-picked grapes. As for sorting methods, in 2009 there were no differences in MOG, while in 2010 mechanical sorting produced better results. Our results question whether the post-harvest sorting techniques used by many estates are effective; particularly as the question has received little attention and no previous research has compared methods. Secondly, our study contribute
Oil crop sustainability assessment: three years of Brassica napus L. cultivation in North East Italy for biodiesel production.
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