Romain Jeantet

Simulating Industrial Spray-Drying Operations Using a Reaction Engineering Approach and a Modified Desorption Method

A predictive tool using a thermodynamic approach has recently been developed to determine several important gas-feed parameters for industrial spray-drying processes. In this approach, a desorption behavior of materials was evaluated and the behavior was linked with overall heat and mass balances over the dryer. Using the desorption behavior of materials and the overall heat and mass balances, a spray-drying software SD2P® was designed at the Institut National de la Recherche Agronomique (INRA) in France. The SD2P® software allows the prediction of optimal inlet drying air temperatures with acceptable accuracy (95–99% accuracy) for spray drying of dairy products. In order to predict detailed quality parameters and stickiness behavior of a product during processing, the reaction engineering approach (REA) was combined with a modified desorption method. A traditional experimental setup is replaced with a new setup, which is described in this article. Drying kinetics parameters were predicted using this new setup. Important gas-feed parameters were predicted using the 1D simulation-based software and compared with SD2P® predictions and are reported here.

Handbook of Food Science and Technology 2: Food Process Engineering and Packaging

This book is a source of basic and advanced knowledge in food science for students or professionals in the food science sector, but it is also accessible for people interested in the different aspects concerning raw material stabilisation and transformation in food products. It is an updated and translated version of the book Science des aliments published in 2006 by Lavoisier. “Science des aliments” is a general and introductory food science and technology handbook, based on the authors’ Masters and PhD courses and research experiences. The book is concise, pedagogical and informative and contains numerous illustrations (approximately 500 original figures and tables). In three volumes), it summarizes the main knowledge required for working in food industries as scientists, technical managers or qualified operators. It will also be helpful for the formation of students in food science and biotechnologies (bachelor’s and master’s degree).

Dimensional Analysis: Principles and Methodology

This chapter examines the principles and methodology involved in dimensional analysis, which should be regarded in this context as a tool for establishing the dimensionless numbers linking the causes of the phenomena studied to its effects, using the homogeneity of dimensions.

Objectives and Value of Dimensional Analysis

The phenomena involved in matter transformation can be described by fundamental momentum, mass and energy transport equations, coupled with equations of chemical or biological kinetics and the constitutive and rheological equations. Boundary conditions of the flow domain and initial conditions are associated with this system of equations. Unfortunately, it is usually impossible to resolve this system of equations because: 1) the form of the differential equations is too complex to be integrated over the entire flow domain, especially given the complex geometry of the industrial equipment;

Handbook of Food Science and Technology 3: Food Biochemistry and Technology

This third volume in the Handbook of Food Science and Technology Set explains the processing of raw materials into traditional food (bread, wine, cheese, etc.). The agri-food industry has evolved in order to meet new market expectations of its products; with the use of separation and assembly technologies, food technologists and engineers now increasingly understand and control the preparation of a large diversity of ingredients using additional properties to move from the raw materials into new food products.nnTaking into account the fundamental basis and technological specificities of the main food sectors, throughout the three parts of this book, the authors investigate the biological and biochemical conversions and physicochemical treatment of food from animal sources, plant sources and food ingredients.

Handbook of Food Science and Technology 1: Food Alteration and Food Quality

This book serves as a general introduction to food science and technology, based on the academic courses presented by the authors as well as their personal research experiences.nnThe authors’ main focus is on the biological and physical-chemical stabilization of food, and the quality assessment control methods and normative aspects of the subsequent processes.nnPresented across three parts, the authors offer a detailed account of the scientific basis and technological knowledge needed to understand agro-food transformation. From biological analyses and process engineering, through to the development of food products and biochemical and microbiological changes, the different parts cover all aspects of the control of food quality.

6 – Case Studies

This chapter provides a collection of examples taken from our research in order to illustrate the application of dimensional analysis discussed in the previous chapters. These examples examine the study of momentum, mass and/or heat transfer and their consequences on a target variable of the process. They involve liquids, solids and gases in different types of isothermal and non-isothermal reactors. The dimensional analyses presented: n– nare first “traditional” in their implementation (sections 6.1–6.3), with a series of examples on the rehydration of powders, the continuous foaming by whipping and the fouling of a plate heat exchanger; n n– nthen, in the case of powder mixing (section 6.4), involve an intermediate variable as defined in Chapter 3, with a view to reduce the configuration of the system without restricting the range of validity of the process relationship; n n– nand finally, focus on processes involving fluids with variable physical properties (sections 6.5 and 6.6). These examples deal with the gas–liquid mass transfer in a mechanically stirred tank containing shear-thinning fluids and the ohmic heating of fluids; the variable property of the fluid is the apparent viscosity which depends on the shear rate and the electrical conductivity varying with temperature, respectively.

Dimensional Analysis: A Tool for Addressing Process Scale-up Issues

This chapter aims to illustrate the advantages of dimensional analysis to address issues of process scale-up or scale-down.

Practical Tools for Undertaking the Dimensional Analysis Process

This chapter addresses certain points raised in Chapter 2, where the principles and methods for carrying out a dimensional analysis were discussed. It aims to highlight the difficulties which users may encounter while undertaking the dimensional analysis process themselves. This involves: – facilitating the process of establishing the list of relevant physical quantities which influence the target variable and helping to evaluate the consequences of an omission/error in the compilation of this list (section 3.),

Dimensional Analysis of Processes Influenced by the Variability of Physical Properties

Food processes involve matter (fluid, emulsion, suspension, etc.), which is placed in equipment in order to be transformed. In numerous cases, one (or several) physical properties of the matters change between the inlet and the outlet of the equipment. There is also very often a spatial and/or temporal distribution of these physical properties within the equipment insofar as they are dependent on various potential fields (composition, temperature, etc.). This dependence has a significant effect on the process and must be taken into account. For instance: – the variation of viscosity with temperature which can be observed within an exchanger during thermal processing. This variation in viscosity with temperature modifies the heat transfer performance of the process when compared to a fluid whose thermo-dependence is negligible;