Preface to the Second Edition The first edition of PRACTICAL DEHYDRATION, published in 1971, was written primarily for the practical dehydrator, rather than for the chemist or theorist, whose interest in the industry might be more abstract or purely scientific. The text tended to concentrate on a range of products likely to be grown and processed in locations where, in the main, moderate equable climates prevailed - predominately Western Europe. Also, the scale of operation hypothesised that a plant, arguably of ’medium’ size, might be viable with an input of 70-80 tonnes of raw produce per 24hr day, or 20,000 tonnes per annum, assuming a 250 day season. Such figures were based on the author’s practical experience in the technical management of three UK plants of this size, all owned by one of the first companies in Great Britain to engage in vegetable dehydration. These operations started in Wisbech in 1934, with six further factories developing during the 1939-1945 war years, prodccing dehydrates for the Armed Services. The company’s products are still on the domestic and export market today, after more than half a century‘s growth in what was initially a war- time industry. Production today is centraliscd in one factory. However, radical changes have occurred in marketing dehydrates in the last two decades, and there has been almost a complete change in the end usage of dehydrated products, and a decline in the number of factories engaged in vegetable drying in the United Kingdom. I This has arisen because of an escalation in operating costs in Western Europe generally, principally in wages, overheads and grossly inflated fuel costs, since the Middle East oil crisis. A change in marketing patterns has evolved, in that dehydrated vegetables have lost some popularity as ‘sui generis’ products in the domestic and catering markets but have found increasing importance as constituents in value-added products of almost infinite variety, such as snack foods, ’impulse foods’, instant soups, garnishes, ethnic specialities, sauces and health foods. Dehydrated or evaporated fruits feature very prominently in health foods and as an addition to breakfast cereals. Manifestly, this new wide range of usage, sometimes of the more exotic foods in dehydrated form, has opened up the possibilities of processing in the developing countries of the world, both tropical and subtropical, and in this context, the chapters on fruit and vegetable processes have been expanded, covering a wider range than was covered in the first edition. These processing procedures, which are described in some detail, have been established following the author’s travels, as a consultant, to many new sources of origin of dehydrates, either in a potential context or in actual operation. This new appraisal of the industry has been arrived at by visits to South America, the Caribbean, Africa, India, Egypt, the Middle East, Western and Eastern Europe. In these areas the function has been to prepare feasibility studies for new enterprises, or to monitor existing production techniques and to guide management in their efforts to improve production methods, and to extricate some factories from difficulties arising from faulty plant design, poor lay-out, hygiene or engineering faults. It is hoped, therefore, that some reference in the ensuing text may be instructive to those who have such difficulties, and may warn others how to avoid the pitfalls which have arisen in some locations. If criticism is implied, an attempt has been made to be absolutely objective, where such problems have occurred. The revitalised market in Western Europe for value-added products has brought new opportunities for the dehydration industry in several interesting new areas, so long as the entrepreneurs accept that this growing market is largely controlled by internationally-based companies with a reputation for quality food products, and anyone seeking to supply the constituents of these products will have to give absolute priority to their own quality control methods, and to comply rigidly with the Specification Schedules which these major buyers impose on their suppliers. It is only those who recognise this concept who have a chance of succeeding in the new era of food dehydration. 2