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1.
Foods ; 9(6)2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32575681

RESUMO

The properties of food products are the result of changes produced in raw materials as a result of process treatments. In the olive oil extraction process, these changes can be observed as differences in quality, nutritional characteristics, taste, and flavor, and are especially due to the time and temperature of the malaxation phase. These parameters are closely related to the mechanical design of malaxer machines. In this study, a new reel model for malaxer machines was designed. The new model was incorporated into an industrial malaxer machine and experimental tests were carried out to study the effects of two different reel designs (modified and unmodified profile) on the rheological characteristics of olive paste, the energy consumption of the plant, and the temperature profile inside the machine. The main commercial parameters of the produced olive oil were studied, as well as the extraction yield and the extraction efficiency of the plant. The malaxer machine equipped with the modified reel showed better homogenization of the paste, which led to improved heat exchange and rheological properties. The results of this study showed that a specific modification of the rotating reel can improve the performance of the malaxer in terms of improving the viscosity of the paste, 127,157.67 (mPa sn) for the malaxer with the modified reel at the beginning of malaxation, reaching a final value of 64,626.00 (mPa sn) at the end. The unmodified malaxer showed an initial viscosity coefficient of 133,754.00 (mPa sn) and a final value of 111,990.67 (mPa sn). This led to a reduction in malaxing times, an increase in the work capacity of the plant, and a reduction in total energy consumption and slowed down the oxidative phenomena responsible for the decrease in the quality of olive oil.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 237: 118373, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32335498

RESUMO

Extra virgin olive oil is a high-quality product with profound health benefits but is susceptible to degradation due to oxidation. Environmental conditions such as temperature, oxygen, and light, promote the oxidation process. From this perspective thermal oxidation stability is of primary concern in terms of food quality and safety. The ability to resist oxidation ensures continued nutritional and economic value. In this study, the thermal oxidation stability of four mono-cultivars of extra virgin olive oil from four different regions of Italy was studied. The samples underwent thermal treatment at 120 °C with measurements taken at regular time intervals over 180 min. To develop a simplified imaging system, the fluorescence characteristics of the samples during thermal exposure were measured using front-face fluorescence and transmittance spectroscopy in order to assess the changes that occur due to thermal exposure. Standard quality indices including; Peroxide value, acidity, K232, and K270, were also measured following IOC (International Olive Council) procedures. Image processing of both color and fluorescence images was done to ascertain cultivar responses to the thermal treatment. Fluorescence peaks associated with polyphenols, oxidation products, and chlorophyll were identified and monitored, and a comparison made between the different cultivars. Fluorescence peaks were observed at emission wavelengths 435, 465, and 570 nm, which are suspected to be products of oxidation and hydrolysis, respectively. The cultivars with a higher concentration of polyphenols showed greater resistance to the formation of oxidation products; an indication that they have a higher thermal stability. The B channel of the RGB color space was identified as being sensitive to changes in UltraViolet (UV) induced fluorescence images due to thermal exposure, and to enable the monitoring of the thermal stability of the different cultivars of extra virgin olive oil.


Assuntos
Azeite de Oliva/química , Imagem Óptica/métodos , Clorofila/química , Fluorescência , Qualidade dos Alimentos , Hidrólise , Itália , Imagem Óptica/instrumentação , Oxirredução , Peróxidos/análise , Feofitinas/química , Polifenóis/química , Temperatura , Tocoferóis/química , Raios Ultravioleta
3.
Vet Ital ; 53(3): 197-205, 2017 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29152702

RESUMO

This paper focuses on a research concerning the operational management of the pig-handling phase, during the period of breeding and before slaughtering. Given the behaviour of these animals during transfers, a particular tool has been designed to manage them in this phase. A total number of 48 animals, divided in 4 groups, were moved without use of the tool (control groups) and by using the tool described in this article. The time required by the control groups to leave the pen ranges from 21 to 125 seconds; while, when the proposed tool was used, the time for the movement of the animals ranged between 10 and 17 seconds. In particular, in the groups where the tool was deployed the 'waiting phase' (before the first animal goes out) lasted less than half of the time of the 'waiting phase' of the control group, thus showing a minimization of the effects of the 'panic phenomenon' among the animals. Thus, the studied device can be considered as valid guide technique, both for the quick exit of the first animal and for those that follow. Once the row has been formed, the animals continue neatly to leave the box. This study also shows that this solution can also be considered appropriate for reducing the identified critical issues in the traditional handling. The need of only 1 worker to move the group of pigs is important to achieve economic saving. The deployment of this tool, thus, make possible to consider the movement of animals no longer a 'critical stage', but as a routine step of the production cycle of pork's meat.


Assuntos
Matadouros/normas , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Bem-Estar do Animal/normas , Cruzamento/métodos , Cruzamento/normas , Suínos , Animais
4.
Vet Ital ; 51(2): 85-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26129658

RESUMO

The environment in the broiler house is a combination of physical and biological factors generating a complex dynamic system of interactions between birds, husbandry system, light, temperature, and the aerial environment. Ventilation plays a key role in this scenario. It is pivotal to remove carbon dioxide and water vapor from the air of the hen house. Adequate ventilation rates provide the most effective method of controlling temperature within the hen house. They allow for controlling the relative humidity and can play a key role in alleviating the negative effects of high stocking density and of wet litter. In the present study the results of experimental tests performed in a breeding broiler farm are shown. In particular the efficiency of a semi transversal ventilation system was studied against the use of a pure transversal one. In order to verify the efficiency of the systems, fluid dynamic simulations were carried out using the software Comsol multiphysics. The results of this study show that a correct architectural and structural design of the building must be supported by a design of the ventilation system able to maintain the environmental parameters within the limits of the thermo­neutral and welfare conditions and to achieve the highest levels of productivity.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas , Microclima , Ventilação , Animais
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