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1.
J Sci Food Agric ; 99(12): 5303-5318, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31032957

RESUMO

BACKGROUND: In several Environmental Product Declarations, the business-to-business carbon footprint (CFCDC ) of durum wheat semolina dried pasta ranged from 0.57 to 1.72 kg carbon dioxide equivalent (CO2e ) kg-1 . In this work, the business-to-consumer carbon footprint (CFCG ) of 1 kg of dry decorticated organic durum wheat semolina pasta, as packed in 0.5 kg polypropylene bags by a South Italian medium-sized pasta factory in the years 2016 and 2017, was assessed in compliance with the Publicly Available Specification 2050 standard method. RESULTS: Whereas CFCDC was mostly conditioned by the greenhouse gases emitted throughout durum wheat cultivation (0.67 vs 1.12 kg CO2e kg-1 ), CFCG was mainly dependent on the use and post-consume phases (0.68 vs 1.81 kg CO2e kg-1 ). CFCG was more or less affected by the pasta types and packing formats used, since it varied from +0.3 to +14.8% with respect to the minimum score estimated (1.74 kg CO2e kg-1 ), which corresponded to long goods packed in 3 kg bags for catering service. Once the main hotspots had been identified, CFCG was stepwise reduced by resorting to a series of mitigation actions. CONCLUSION: Use of more eco-sustainable cooking practices, organic durum wheat kernels resulting from less impacting cultivation techniques, and renewable resources to generate the thermal and electric energy needs reduced CFCG by about 58% with respect to the above reference case. Finally, by shifting from road to rail freight transport and shortening the supply logistics of dry pasta and grains, a further 5% reduction in CFCG was achieved. © 2019 Society of Chemical Industry.


Assuntos
Pegada de Carbono/economia , Manipulação de Alimentos/economia , Alimentos Orgânicos/economia , Triticum/química , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Alimentos Orgânicos/análise , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
2.
J Food Sci ; 83(1): 129-137, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29178150

RESUMO

In this work, the main constraint (that is, beer chilling and chill haze removing) of the current beer conditioning techniques using Kieselguhr filtration and Polyvinylpolypyrrolidone (PVPP) treatment was overcome by developing a novel higher-throughput conditioning process, operating at room temperatures with no use of filter aids. The effect of filtration temperature (TF ) in the range of 0 to 40 °C on the hydraulic permeability of ceramic hollow-fiber (HF) membranes with nominal pore size of 0.2 to 1.4 µm, as well as on their limiting permeation flux (J* ) when feeding precentrifuged rough beer, was preliminarily assessed. When using the 1.4-µm HF membrane operating at TF ≥ 20 °C, it was possible to enhance the average permeation flux at values (676 to 1844 L/m2 /h), noticeably higher than those (250 to 500 L/m2 /h) characteristics of conventional powder filtration. Despite its acceptable permanent haze, the resulting beer permeate still exhibited colloidal instability. By resorting to the commercial enzyme preparation Brewers Clarex® before beer clarification, it was possible to significantly improve its colloidal stability as measured using a number of European Brewing Convention forcing tests, especially with respect to that of precentrifuged rough beer by itself. By combining the above enzymatic treatment with membrane clarification at 30 °C across the ceramic 1.4-µm HF membrane module, it was possible to limit the haze development due to chilling, sensitive proteins, and alcohol addition to as low as 0.78, 4.1, and 4.0 EBC-U, respectively, the enzymatic treatment being by far more effective than that using PVPP. PRACTICAL APPLICATION: A novel Kieselguhr- and PVPP-free rough beer conditioning process at room temperatures was set up. By submitting precentrifuged rough beer to commercial preparation Brewers Clarex ® and then to membrane clarification at 30 °C across a ceramic 1.4-µm hollow-fiber membrane module, it was possible to obtain a clear and stable beer with a throughput (1306 ± 72 L/m2 /h) by far higher than that (250 to 500 L/m2 /h) characterizing the current powder filters. The haze development due to chilling, sensitive proteins, and alcohol adding was by far lower than that observed when microfiltering PVPP-pretreated rough beer.


Assuntos
Cerveja/análise , Terra de Diatomáceas/análise , Povidona/análogos & derivados , Cerâmica/química , Filtração , Manipulação de Alimentos , Permeabilidade , Polifenóis/química , Povidona/análise , Pós , Proteínas/química , Reprodutibilidade dos Testes , Temperatura , Trichoderma/enzimologia
3.
J Food Sci ; 81(7): C1603-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27239804

RESUMO

The ethyl carbamate (EC) content of a wine after a given temperature-time storage was theoretically predicted from the potential concentration of ethyl carbamate (PEC), as determined via an accelerated EC formation test. Such information was used to decide whether an enzymatic treatment was needed to reduce the wine urea level before bottling/aging. To this end, 6 white, red, and rosé wines, manufactured in Italy as such or enriched with urea, were tested for their PEC content either before or after enzymatic treatment using a purified acid urease preparation derived from Lactobacillus fermentum. The treatment was severely affected by the total phenolic content (TP) of the wine, the estimated pseudo-first-order kinetic rate constant for NH3 formation reducing by a factor of approximately 2000 as the TP increased from 0 to 1.64 g L(-1) . Such a sensitivity to TP was by far greater than that pertaining to a killed cell-based enzyme preparation used previously. Urea hydrolysis was successful at reducing EC concentration in wines with low levels of TP and other EC precursors.


Assuntos
Manipulação de Alimentos/métodos , Limosilactobacillus fermentum/enzimologia , Fenóis/metabolismo , Ureia/metabolismo , Urease/metabolismo , Uretana/metabolismo , Vinho/análise , Carcinógenos/metabolismo , Humanos , Itália , Cinética , Temperatura
4.
J Agric Food Chem ; 55(7): 2590-6, 2007 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-17328559

RESUMO

UNLABELLED: The specific activity of a whole cell acid urease preparation was tested in five wines manufactured in the Apulia region of Italy in the 2003 vintage at both short and long treatment times, thus confirming the validity of the pseudo-first-order kinetic model to describe urea removal in real wines. The ratio between the experimental pseudo-first-order kinetic rate constant (kIe) for any real wine tested and that (kI) referred to a model wine solution having the same composition and pH reduced from about 0.21 to 0.02 as the overall content of phenolic compounds (P) increased from 109 to 853 g m-3 of gallic acid equivalent (GAE). The specific inhibitory effect of such compounds was explained by accounting for the equilibrium constant (KP) of the reaction of polyphenols with acid urease, which was found to be about 21 g of GAE m-3 for the real wines tested, whereas it ranged from about 16 to 45 g of GAE m-3 when the model wine solution was enriched with tannins extracted from grape seeds or skins, respectively. A sequential experimental procedure consisting of accelerated acid urease tests at high doses of enzyme followed by accelerated ethyl carbamate tests on the resulting acid urease treated wine was recommended to assess preliminarily the technoeconomic feasibility of the acid urease hydrolytic process for the wine of concern. KEYWORDS: Acid urease; real and model wines; phenolics; pseudo-first-order kinetic rate constant; inhibitory effect; urea degradation kinetics.


Assuntos
Ureia/metabolismo , Urease/metabolismo , Vinho/análise , Etanol/análise , Itália , Cinética , Limosilactobacillus fermentum/enzimologia , Modelos Biológicos , Fenóis/farmacologia , Ureia/análise
5.
Biotechnol Appl Biochem ; 40(Pt 2): 123-31, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15003107

RESUMO

The recovery of sodium lactate from model solutions by ED (electrodialysis) was studied using a sequential experimental procedure so as to assess the main engineering parameters (i.e. ion transport numbers in solution and electro-membranes, effective solute and water transport numbers, effective membrane surface area, surface resistances and limiting current intensity) affecting ED stack design and/or optimization. Of the major factors that determine the performance of this ED process, Omega (the current efficiency) was about 88% in the constant-current region, while epsilon (the specific energy consumption) increased from 0.14 to 0.31 kWh x kg(-1) for a solute recovery yield of 95% and j (current density) increasing from 112 to 337 A x m(-2). The specific-resistance values of the anion- or cation-exchange membranes were found to be five or two times greater respectively than those extracted from literature and measured in aqueous NaCl solutions.


Assuntos
Adenosina Trifosfatases/química , Adenosina Trifosfatases/isolamento & purificação , Proteínas de Transporte/química , Proteínas de Transporte/isolamento & purificação , Diálise/métodos , Eletroquímica/métodos , Proteínas de Membrana/química , Proteínas de Membrana/isolamento & purificação , Modelos Químicos , Lactato de Sódio/química , Lactato de Sódio/isolamento & purificação , Simulação por Computador , ATPases Mitocondriais Próton-Translocadoras
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