The project on microwave processing of food is being carried out by research groups of theUniversity of Bristol.
Over the past five years, the work has particularly focused on processing and preservation systems for the safe and efficient production of foods, including microwave pasteurisation and sterilisation.
The overall aim of this project will be to establish an understanding of the relationship between microwave and food parameters during processing and maintenance of food quality and safety. This will be achieved bу the development of computer models of process in combination with experimental investigations at pilot-plant scale.
The most promising commercial applications for microwave processing in the areas of pasteurisation are:
1. Identify the most promising operational strategies required in terms of microwave power, frequency, process time and configuration of microwave cavity, to ensure foods safety and quality;
2. Determine the safe storage lives for microwave pasteurisation products;
3. Investigate pressure build-up and other factors controlling package failure during processing;
4. Provide product data on composition, temperature and configuration of the raw materials required for control systems in programmable microwave units;
5. Provide processing data on the time, power and field distribution required to temper particular raw materials to an optimum state for the next processing operation.
microwave - микроволновыйin terms of - исходя из, на основе
at pilot- в масштабе опытного заводаfailure - повреждение
promising - многообещающийto temper - делать
Machine-tools are used toshape metals and other materials. The material to be shaped is called theworkpiece, Most machine-tools are nowelectricallydriven. Machine-tools with electrical drive are faster and moreaccurate than hand tools: they were an important element in thedevelopment of mass-production processes, as they allowed individual parts to be made in large numbers so as to beinterchangeable.
All machine-tools havefacilities for holding both the workpiece and the tool, and for accurately controlling the movement of the cutting toolrelative to the workpiece. Most machining operations generate largeamounts of heat, and use coolingfluids (usually a mixture of water and oils) for cooling andlubrication.
Machine-tools usually work materials mechanically but other machining methods have been developed lately. They include chemical machining,spark erosion to machine very hard materials to any shape by means of a continuous high-voltagespark (discharge) between an electrode and a workpiece. Other machining methods includedrilling using ultrasound, and cuttingby means of a laserbeam. Numerical control of machine-tools andflexible manufacturing systems have made it possible for complete systems of machine-tools to be used flexibly for the manufacture of arange of products.