This book resulted from many years of teaching engineering aspects of food tech nology at the Agricultural University ofWageningen, The Netherlands. In the course of those years the subject matter of teaching has been written down and placed at the student's disposal. The Dutch text has been reconsidered and revised several times. Eventually the question arose whether it would be advisable to transform and translate the text in order to transfer available knowledge and experience to others interested in the relatively new branch of food science that food process engineering is. This question has been answered in the affirmative. Up to now only a few books deal with food process engineering; some are rather superficial and evidently meant as introductory, other ones have in our opinion too much emphasis on chemical engineering and too little on food process engineering. We believe - and this will be elucidated at some length in the Introduction - that food process engineering is in many respects a very specific branch of engineering, allied to but certainly different from chemical engineering. We have always endeav oured to show similarities between various branches, stressing at the same time how ever the differences and explaining the why and wherefore of them. The present book illustrates this approach. It considers engineering, process en gineering and food process engineering as ranking in this order of rising importance.