Eight years have elapsed since the publication of the first edition. During this period significant improvements in food processing have taken place, and new food products have been developed. Practically all of this advancement was stimulated by the impact of World War II on the economy of the nation.

There have been advances, too, in design of equipment and in the basic knowledge of food technology.

In revising the book, attempts have been made to incorporate new methods and products that have been born since the first edition. Efforts have also been made to eliminate errors, both technical and typographical, of the first edition. Aid has been given in this respect by reviewers of the first edition, and by others who have been kind enough to point out such errors. The author expresses his appreciation to all of these critics. It is probably too much to hope that the present edition will be free of all errors, but every effort has been made to keep them to a minimum.

The importance of food technology is becoming increasingly recognized by colleges and universities throughout the country, as evidenced by the fact that many of these institutions now have well-organized food technology curricula. It is hoped that this book may serve a useful purpose in these courses of study.

The author wishes to express his appreciation to all who have had a part in the revision, and particularly to his wife for her help in preparing the index, and to Mr. G. G. Hawley, Editor-in-chief of the publishers, for his many helpful suggestions.