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Modeling physicochemical properties plays an important role in the function of animal and plant preparations which are widely used in the food processing. The study presents some functional characteristics of 21 randomly selected protein preparations subjected to the examination under the same analytical conditions. All examined preparations were highly variable in their composition, solubility, emulsifying and foaming properties. It has been confimed that the evaluation of protein preparation hydrophobicity is possible using different empirical or computational methods. The surface hydrophobicity value may be used to extend complex laboratory characterization of protein preparations.
Fruit and vegetables are a valuable and essential component of a human diet. Unfortunately, the widespread and increasingly popular use of pesticides has largely magnified quantities of pesticide residues in these plant products. Among the best methods for removal of these contaminants from food of plant origin are food processing technologies, which affect the levels of pesticide residues to various degrees. The aim of this study was to compare the effects of different water and thermal processing treatments on pesticide residue concentrations in selected fruit and vegetables obtained from controlled field and tunnel trials. Black currants, broccoli, strawberries and tomatoes sprayed with plant protection products were analyzed. Washing by immersion in chlorine and in ozonated water as well as boiling were used to assess the removal of eleven pesticides in blackcurrants, broccoli, strawberries and tomatoes. Processing factors, which were determined for each combination of a pesticide, commodity and processing method, ranged between 0.03 and 1.66. Washing in ozonated water was more effective than washing in chlorinated water. However, high temperature at boiling caused a significant decrease in the concentration of most compounds (up to 97%), although there were some exceptions. The thermal treatment proved to be the most effective technological process removing pesticide residues from different commodities. The water and thermal processing technologgies tested in this experiment are promising methods for fast and simple removal of pesticide residues from broccoli, black currants, strawberries, tomatoes and possibly other commodities.
The effect of physicochemical factors: temperature (20°C, 60°C, 100°C, 121.1°C), pH (2-9), inorganic and organic components, i.e. sodium chloride (5%, 10%, 15%, 20%), carbohydrates: glucose and starch (10%, 20%, 40%), proteins: casein (2.5%, 5%, 10%) and their combinations (e.g. prolonged incubation time at low pH) on in vitro detection of specific fragment of L. monocytogenes iap gene (453 bp) carried out using polymerase chain reaction (PCR) were examined. The possibility of detection of the iap gene during apple and tomato processing as well as in their processed products was also tested. Results showed that two factors hindering detection of the iap gene were casein at all concentrations and processing applied to apples (initial pH 2.5-3.0) and tomatoes (initial pH 4.0-4.5) as well as prolonged incubation in low pH at 60°C.
Ultrasonic is a rapidly growing field of research, which is finding increasing use in the food industry for both the analysis and modification of food products. The sound ranges employed can be divided into high frequency, low energy diagnostic ultra- sound and low frequency, high energy power ultrasound. The former is usually used as a non-destructive analytical technique for quality assurance and process control with particular reference to physicochemical properties such as composition, structure and physical state of foods. Nowadays, power ultrasound is considered to be an emerging and promising technology for industrial food processing. The use of ultrasound in processing creates novel and interesting methodologies which are often complementary to classical techniques. Various areas have been identified with great potential for future development: crystallisation, degassing, drying, extraction, filtration, freezing, homogenisation, meat tenderization, sterilization, etc. There is a wide scope for further research into the use of ultrasound in food processing both from an industrial and academic viewpoint.
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Dust emission rates from food processing

86%
A field study was performed to develop emission rates for dust exposure at a food processing facility. Eight 2-hour periods were monitored over 2 days. Area total suspended particulate samples were collected on 37 mm polyvinyl chloride filters with 5 µm pore size according to NIOSH Method 0500. Filters were analyzed gravimetrically. Ventilation and production activity data were collected during air sampling. Two mass balance models were used to calculate emission rates. The first was an experimental mass balance model, with the mass of contaminant generated determined by air flow and concentration measurements at room exit and entry points. The second treated the work environment as a completely mixed space, utilizing ventilation and area concentration measurements. Emission rates generated from mass balance models ranged from 2.09-542 mg/min for the various processing operations and food products. Process emission rates with production activity data allow estimation of dust exposure in similar facilities, and help direct development of exposure control strategies.
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Thermal conductivity of food products

72%
The presented work is focused on the food thermal characteristics calculation methods (heat conductivity coefficient  and thermal diffusivity coefficient a). Thermal characteristics of food are important in food industry and define the intensiveness of technological processes of food refrigeration and thermal treatment, energy consumption for their realization and technological equipment production rate. They are also needed for the building and validation of mathematical models of heat transfer in food products which are useful in the design and optimisation of freezing, heating, cooking and cooling processes and equipment. It is not easy to define the food thermal characteristics. Difficulties arise from their heterogeneity, high labour consumption and complexity of experimental sets. Methods for experimental determination of heat conductivity coefficient  and thermal diffusivity coefficient a based on the regular method mode require the α → ∞ condition, which is the case of high speed of the environment which flows around the test sample, as in the case of boiling or condensing. Using the method presented in this article it is possible to determine the heat conductivity  and thermal diffusivity coefficient a even in the absence of the condition α → ∞.
Abstract. This paper highlights the evolution of nanoscience and nanotechnologies from the global perspective and their potential application in food Systems including meat Processing. Nanotechnology has its roots in a talk delivered in 1959 by physicist Richard Feynman to the American Physical Society. Nanoscience refers to components properties at nanoscale and nanotechnology refers to process or processes used in the manufacture and/or biofabrication of new materials measured at nanoscale. Nanotechnology offers a wide range of opportunities for the development of innovative products and applications in food system. Functional foods, nutraceuticals, bioactives, farmafoods, etc. are very recent example of it. Nanotechnology and nanomaterials are a natural part of food Processing and conventional foods, because the characteristic properties of many foods rely on nanometer sized components. Some of the areas where nanotechnologies are set to make a difference in meat processing in near future relate to intelligent packaging of meat and meat products, meat derived bioactive peptides, proand pre-biotics inclusion in processed meat products, fat based nanoemulsions for antioxidant delivery, nanosensors and nanotracers for meat biosecurity tracing and nanostructured meat products with defined functions. New horizons for nanotechnology in meat science may be achieved by further research on nanoscale structures and methods to control interactions between single molecules. However, it shall be mentioned that nanotechnologies and nanomaterials are calling for their regulations and safety assessment as some of the materials are new and their safety never tested before.
Residues of plant protection products can be nowadays found in almost all samples of fruits as even if their application was carried out with respect to standards of Good Agricultural Practice. The intake of these compounds with food of plant origin may result in various disorders and diseases. Since the use of plant protection agents seems unavoidable, it is necessary to treat contaminated food material to eliminate or reduce residues content within food products. Ozone is utilized for elimination of biological and chemical contaminants in various environmental matrixes. Since its utilization in food industry has been permitted many experiments were conducted in order to determine its efficiency and side effects on food quality. The goal of this paper is to contribute to a discussion on the ozonization as a process leading to reduction of pesticide residues on plant surface.
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