Woodhead Publishing Series in Food Science, Technology and Nutrition: Number 280 A Complete Course in Canning and Related Processes Fourteenth Edition Volume 1: Fundamental Information on Canning Revised by Susan Featherstone AMSTERDAM • BOSTON • CAMBRIDGE • HEIDELBERG LONDON • NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Woodhead Publishing is an imprint of Elsevier Introduction 1 Why this series of books? The name of this series of books, A Complete Course in Canning and Related Processes, indicates that it is intended as a source of information on canned foods. The reader will find here factual and reliable data on all the important facets of canned foods, such as product formulations, manufacturing procedures, food laws, sanitation, sterilisation, spoilage, containers, food plant characteristics, warehousing, and others. This 14th edition of these books builds on the excellent foundations laid by the authors who contributed to the original articles that were published in the early 1900s in the magazine The Trade, published in Baltimore in the United States of America (it was later called The Canning Trade and is now called Food Production Management). In 1906 the articles were published in a book entitled A Complete Course in Can- ning: Being a Thorough Exposition of the Best Practical Methods of Hermetically Sealing Canned Foods, and Preserving Fruits and Vegetables: Originally Republished from the Serial Articles Appearing in ‘The Canning Trade,’ the Canned Food Author- ity. This book was regularly updated with contributions from various authors, and between 1969 and 1987 the 9th through the 12th editions were edited by Dr Anthony Lopez. Originally there was only one book, but to live up to the name of “complete” in 1975 the 10th edition was expanded into two volumes, and in 1987 the 12th edition was further expanded into three volumes. In 1996 the 13th edition was edited by Dr Douglas L. Downing. When this work first appeared as a serial article in the pages ofThe Trade, the claim “complete” seemed boastful, if not questionable. At the beginning of the twentieth cen- tury, the canning industry was, if not in its infancy, at best in its kindergarten age and the amount of production was a fraction of what it is today. Factory equipment and layout were crude and just commencing to develop; quality and grades of products were as varied and as numerous as the producers, because food laws were then nonex- istent. Science, as applied to canning and food preservation, was just looming on the horizon. There were no set, definite formulae, except those that experience had taught through dint of heavy cost and that were accordingly carefully nursed and protected by their possessors, the “expert processors.” These “expert processors” lorded over the work and the men who employed them and refused to divulge their “secrets.” Losses from spoilage, as well as from poor quality, were accepted as normal. At the turn of the century, the industry had little or no scientific knowledge or assistance to depend upon. The fact that there were no definite formulae obtainable, in printed form or other- wise, at that time, brought the canners of that day, and the new men wishing to enter the industry in particular, to The Canning Trade, as the sole source of canning infor- mation, asking for direction on the canning of the particular product in which they were interested. Since his earliest association with the industry, in the founding of The Trade, later called The Canning Trade, in 1878, its first editor, Edward S. Judge, began xxvi Introduction the accumulation of information on processing and handling, keeping these findings in a big black book – a sort of treasure chest. From this source of information, type- written recipes/formulae were given free to inquirers. The demand was so heavy that it forced consideration of publication of the information in the weekly issues of the industry’s journal, The Canning Trade. To get more recipes, a competition was set up that offered several thousand dollars in prizes for the best, or most complete, formu- lae for the canning, preserving, or pickling of all the various products, the stipulation being that all offerings became the publisher’s property, whether or not they won prizes. Responses were prompt and plentiful, coming from all manner of “processors,” expert chefs, cooks, etc., including the most famous and most experienced. The awards were paid, and then began the compilation of the work. A Complete Course in Canning was, accordingly, the expression of the best experience existent, its formulae as dependable as possible. As in previous revisions of this book, this 14th edition has been brought up to date. The aim and desire of these revisions has been to help producers advance the safety and success of food production of this kind, to warn against the dangers and the pitfalls, to keep producers upon safe ground, and to make products safe for public consumption. A Complete Course in Canning, as the textbook of this industry, used as it is throughout the entire world, affords the opportunity to put information into the hands of the individuals who need it and can make the best use of it. It is intended to be a compendium of the industry’s researches and studies. This 14th edition has more detail on food microbiology and a new chapter on microbiological and nonmicro- biological spoilage. To keep abreast of a very important subject for today’s canners, there is a new chapter on reducing energy consumption. The series of books has been converted to primarily metric and centigrade and the focus is more on general canning legislation and guidelines and is less specifically aimed at the American canner but does use the excellent base of the U.S. FDA and USDA legislation and guidelines, which have been used as building blocks for much of the text. Mechanical equipment and construction of the factory itself have so advanced and improved that no canner should fail to check carefully with the latest and best sources of information. To that end, they should consult the builders of factory buildings, mak- ers of canning and preserving machinery, manufacturers of metal and glass containers, commercial horticulturalists, specialists in food labels, etc. Every such firm willingly furnishes detailed information, without obligation, and their recommendations can be relied upon. It is impossible to lay down a uniform factory plan, mechanical equip- ment, or label design. Every individual or firm wants to carry out personal ideas or desires, and it is well that this is so; but we urge all to call in these experts and have confidence in them, as a surety that the best possible job, under the circumstances, in quality, safety, and cost of production, is being done. Despite the fact that the greatest care has been exercised in the preparation of the recipes, formulae, times, and directions given in this book, they should, nevertheless, be taken largely as suggestive only, as a reliable working basis, to be altered or changed to fit particular conditions. The formulae given herein are practical and ready to use; they have all been tried and proven, but a change in temperature, altitude, or raw material quality or composition; difference in soil or fertiliser used; a wet or dry season; and a hundred and one other causes may necessitate a change in the process. As was said in Introduction xxvii the first edition of this book, and repeated here: “there is one reservation that goes with this: ‘Considerable Common Sense Must Be Added To All Recipes and Formulae.’ As a result, “No Large Pack of a New Product Should Ever Be Produced Until a Trial Batch Has Been Made.” To quote the last paragraph from the Introduction in the first edition of this work: “If used judiciously, in this manner, these formulae will be found satisfactory, differing possibly with different processors, as is natural, but worthy of the high approval set upon them when they were first published.” Keeping careful check upon raw materi- als received, and on factory operations as they progress, may save heavy losses from spoilage or a lowering of quality. It is too late to check after the product is in the ware- house. Similarly, all the guidance and information given should be considered and then adapted accordingly to the specific factory and processing conditions and product type. 2 A brief history of canning technology It is more than two centuries (Figure 1) since Nicholas Appert published his book in which he documented his methods for producing heat-preserved foods in hermetically sealed containers. His invention has been incredibly successful and has contributed in a significant way to the improvement of nutrition and health of consumers all over the world. Today approximately 50 billion1 (Featherstone, 2012) cans of food are manu- factured and consumed every year, globally. 3 Nicholas Appert discovers and documents a safe way of heat-preserving food The sixteenth and seventeenth centuries were a time of great scientific advancement in the areas of chemistry, mathematics, and physics. This was known as the Scientific Revolu- tion, which laid the foundation for the Age of Enlightenment in the eighteenth century, a period in which science became popular with the ordinary person, and an increasingly literate population was hungry for knowledge, for information, and to learn. Evening science lectures, with demonstrations, were very popular as a form of entertainment for the work- ing class. In addition, the Industrial Revolution was taking place in Europe in the eighteenth and nineteenth centuries. Great strides were made in the areas of textiles, steam generation, and metallurgy. Steam generation was much more efficient; fossil fuels were used for the first time, instead of wood-based fuel, resulting in a much more efficient source of energy.