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[...]... Thus it is important to understand the chemical, structural and microbiological aspects of food in so far as they contribute P.G Smith, Introduction toFood Process Engineering, Food Science Texts Series, DOI 10.1007/978-1-4419-7662-8_1, C Springer Science+Business Media, LLC 2011 1 2 1 An Introduction toFood Process Engineering to an understanding of the process, that is, how to develop, design, operate... basis of food processing technology At the heart of processengineering is the concept of the unit operation Thus the principles which underlie drying, extraction, evaporation, mixing and sterilisation are independent of the material which is being processed Once understood, these principles can be applied to a wide range of products The overall purpose of foodprocessengineering then is to design processes... transfer process equipment depends upon being able to predict the rate at which heat is transferred to a food stream being sterilised In turn this requires knowledge of the physical behaviour of the fluid, in short an understanding of fluid flow An Introduction toFood Process Engineering 3 and rheology This allows judgements to be made about how best to exploit the flow of material, for example whether... pertinent to the aim of this book, thermodynamics is able to specify the thermal energy changes required to bring about certain physical changes in a system: an increase or decrease in temperature; a change of state from liquid to vapour or from solid to liquid Thus thermodynamics predicts the heat input required to raise the temperature of a food, to evaporate water from an aqueous food solution or to thaw... progress can be made in the application of heat transfer in food processing without a knowledge of the relevant heat transfer coefficient The overall design of the foodprocess now moves onto the specification of instrumentation and process control procedures, to detailed costing and economic calculations, to detailed mechanical design and to plant layout However, all of these latter stages are beyond... 10.6.1 Introduction 10.6.2 The Procedure to Find Total Process Time 10.6.3 Heat Transfer in Thermal Processing 10.6.4 Integrated F Value 10.7 Retorts for Thermal Processing 10.7.1 The Batch Retort 10.7.2 Design Variations 10.7.3 Continuous Retorts ... illustrate the variety of reasons for processing food materials Although foods are always liquid or solid in form, many foods are aerated (e.g ice cream), many processes utilise gases or vapours (e.g steam as a heat source) and many storage procedures require gases of a particular composition Thus it is important for the food technologist or the food engineer to understand in detail the properties and behaviour... 501 Chapter 1 An Introduction toFood Process Engineering A process may be thought of as a sequence of operations which take place in one or more pieces of equipment, giving rise to a series of physical, chemical or biological changes in the feed material and which results in a useful or desirable product More traditional definitions of the concept of process would not include the term... conditions required to achieve the necessary output of product It is a quantitative science in which accuracy and precision, measurement, mathematical reasoning, modelling and prediction are all important Foodprocessengineering is about the operation of processes in which food is manufactured, modified and packaged Two major categories of process might be considered; those which ensure food safety, that... importance of, the food industry, and the rise of the biotechnology industries, it is ever more relevant to do so Processengineering is concerned with developing an understanding of these operations and with the prediction and quantifying of the resultant changes to feed materials (such as composition and physical behaviour) This understanding leads in turn to the specification of the dimensions of process equipment . being processed. Once understood, these principles can be applied to a wide range of products. The overall purpose of food process engineering then is to design processes which result in safe food. it is important to understand the chemical, structural and microbiological aspects of food in so far as they contribute 1 P.G. Smith, Introduction to Food Process Engineering, Food Science Texts. or contain a significant proportion of, food technol- ogy or food engineering. This is a new book on food process engineering which treats the principles of processing in a scientifically rigorous