Preface where possible.Information available on the organic acids is expanding daily and this book should be a decidedly relevant source of information in both the food industry,which is,after all,one of the strongest indus- tries in the world,as well as several disciplines in the academic world, including microbiology food scence food technology,biochemistry,and biotechnolog ces from both the formal and the informal s es all ove om 、this bo ems are miar all over the world.Numerous probemin food preservation are encountered even in developed countries,who also claim to be leaders in the fields of food production,food processing,and food safety. Numerous books have,over the last century(the authors found one as early as 1905!)and longer,been published on food preservation,which include methods of preservation,as well as the variety of food additives. Howe rece fully a orga even though may be assumed that researchers,scienti even food technologists have recognized the need for such a single vol ume that covers most of the information (the broad and vast spectrum) available on the organic acids as natural food preservatives.Because many of these acids are naturally produced by various microorganisms, occur naturally in foods,and inhibit the growth of most mic isms,they have been of great value as p rvatives.Although org acids ha e for sed in iallv od fo as additiv espe es, r as es,have y been cept of compiling all the relevant important information on the organic acids into one descriptive book may just be the ultimate vade mecum for any scientist,researcher,food processor,or food technologist
xviii Preface where possible. Information available on the organic acids is expanding daily and this book should be a decidedly relevant source of information in both the food industry, which is, after all, one of the strongest industries in the world, as well as several disciplines in the academic world, including microbiology, food science, food technology, biochemistry, and biotechnology. Audiences from both the formal and the informal sectors from countries all over the world will be able to benefit from this book, even developing countries. Food-related problems are similar all over the world. Numerous problems in food preservation are encountered even in developed countries, who also claim to be leaders in the fields of food production, food processing, and food safety. Numerous books have, over the last century (the authors found one as early as 1905!) and longer, been published on food preservation, which include methods of preservation, as well as the variety of food additives. However, it is surprising to find that there appears to be no book, older or recently published, that fully addresses the organic acids, even though it may be assumed that researchers, scientists, industrial processors, and even food technologists have recognized the need for such a single volume that covers most of the information (the broad and vast spectrum) available on the organic acids as natural food preservatives. Because many of these acids are naturally produced by various microorganisms, occur naturally in foods, and inhibit the growth of most microorganisms, they have been of great value as preservatives. Although organic acids have for many years been used in food, especially processed food, as additives, either as flavorants or preservatives, have they really been assessed as to their continuing effectiveness and sustainability? The concept of compiling all the relevant important information on the organic acids into one descriptive book may just be the ultimate vade mecum for any scientist, researcher, food processor, or food technologist
Acknowledgments The authors wish to thank the personnel of the Library and Information Centre at the CUT,and in ing task of collecting all the data.the absolutely amaz A very special thank you also to Kaylene Maasdorp and Marelize van Rooyen for taking care of the referencing. xix
xix Acknowledgments The authors wish to thank the personnel of the Library and Information Centre at the CUT, and in particular, Anita du Toit for the absolutely amazing task of collecting all the data. A very special thank you also to Kaylene Maasdorp and Marelize van Rooyen for taking care of the referencing
Author biographies Maria Theron is a full-time researcher in the Unit for Applied Food Science and Biotechnology (UAFSB)at the Central University of Technology (CUT),Free State in Bloemfontei South Africa.She holds a PhD in med- ogy m the Uni of the nte(UFS medical sci .She wrked sity and lecturer in th Faculty of Health Sciences at the UFS from 1984-2004,her research focusing on antimicrobial resistance develop- ment in anaerobic bacteria.In 2005 she entered the food arena,but her research focus remained on antimi- crobial activity and efficacy ("differ- ent song,same tune").She is currently steering a project on "Organic Acids as Antimicrobials in Food Preservation"within the research niche reaECB funded by the National Research Foundation (NRF) outh xxi
xxi Author biographies Maria Theron is a full-time researcher in the Unit for Applied Food Science and Biotechnology (UAFSB) at the Central University of Technology (CUT), Free State in Bloemfontein, South Africa. She holds a PhD in medical microbiology from the University of the Free State (UFS). She worked as medical scientist and lecturer in the Faculty of Health Sciences at the UFS from 1984–2004, her research focusing on antimicrobial resistance development in anaerobic bacteria. In 2005, she entered the food arena, but her research focus remained on antimicrobial activity and efficacy (“different song, same tune”). She is currently steering a project on “Organic Acids as Antimicrobials in Food Preservation” within the research niche area of the UAFSB, funded by the National Research Foundation (NRF) of South Africa
Author biographies Ryk Lues is currenty full profes. sor and hea the Programme Enviromental Heath at theCentra University of Technology (CUT),Free State,South Africa.He also heads the Unit for Applied Food Safety and Biotechnology at the CUT.Lues holds an MSc (microbiology)and a PhD (food science)from the University of the Free State and his field of spe cialization comprises organic acid biotechnolo nd social-behavioral affe nygiene.He to dat e,autho numerous arti es ISI-accredite journals and contributed to a number of books and book chapters on top. ics related to food microbiology,research methodology,and food hygiene systems auditing and management.He also supervised several masters, doctorate,and postdoctorate students and often acts as an external exam- iner,referee,and auditor
xxii Author biographies Ryk Lues is currently full professor and head of the Programme Environmental Health at the Central University of Technology (CUT), Free State, South Africa. He also heads the Unit for Applied Food Safety and Biotechnology at the CUT. Lues holds an MSc (microbiology) and a PhD (food science) from the University of the Free State and his field of specialization comprises organic acid biotechnology and social–behavioral aspects affecting food microbiology and hygiene. He has, to date, authored numerous articles in ISI-accredited journals and contributed to a number of books and book chapters on topics related to food microbiology, research methodology, and food hygiene systems auditing and management. He also supervised several masters, doctorate, and postdoctorate students and often acts as an external examiner, referee, and auditor
chapter one Introduction 1.1 The evolution of preservation with organic acids:From stone age to space age 1.1.1 More than a century of preservation with organic acids The ability to store large quantities of food has plaved a pivotal role in vation dates back to the d the first use of biological ods has b een traced back with ev der e of fer mentation process s used in producing beer,wine,vi egar,bread,cheese, butter,and yogurt(Soomro,Masud,and Anwaar,2002 Evidence also exists that points to a notable award that was offered by the Emperor Napoleon of France in 1787 for anyone who could propose a way to preserve the food intended for the soldiers in the French armies. This award was won in 1809 by Nicholas Appert for his idea to put food in bottles,stopper them,and heat the contents,killing bacteria and pre- venting further contamination.However,he was apparently not aware at the time of the existence of bacteria and that thev were the cause of the Pollage In 1819 Peter Dunrand used metal containers to apply the same ntainers w e called the origin rd can"(Saint Xav ier Iniv The of fo sity,2000) e was d in 1864 by Louis Pasteur who we dthat microor s were the ca such nation. sequently f and that sealed containers could be used to preserve food by preventing recontamination from atmospheric air. In 1940.a maior development in the distribution and storage of foods was achieved,when low-cost home refrigerators and freezers became avail- able.Other developments followed and included artificial drving.vac. uum packaging,ionizing,radiation,and chemical preservation(Soomro Masud,and Anwaar,2002).A combination of techniques in which acids have played an important role have emanated as part of consequent pres rotocols for various foodstuffs (Hsiao and Siebert.1999).On the fundamental principles of food safety has been based on the division of foods into lo acid and high- and th on of preservation trea tments (Nakai 20 applica- to the entire food preservation process that can be traced back centuries,the use 1
1 chapter one Introduction 1.1 The evolution of preservation with organic acids: From stone age to space age 1.1.1 More than a century of preservation with organic acids The ability to store large quantities of food has played a pivotal role in mankind’s development. Evidence of food preservation dates back to the postglacial era, from 15,000 to 10,000 BC, and the first use of biological methods has been traced back to 6000 to 1000 BC, with evidence of fermentation processes used in producing beer, wine, vinegar, bread, cheese, butter, and yogurt (Soomro, Masud, and Anwaar, 2002). Evidence also exists that points to a notable award that was offered by the Emperor Napoleon of France in 1787 for anyone who could propose a way to preserve the food intended for the soldiers in the French armies. This award was won in 1809 by Nicholas Appert for his idea to put food in bottles, stopper them, and heat the contents, killing bacteria and preventing further contamination. However, he was apparently not aware at the time of the existence of bacteria and that they were the cause of the spoilage. In 1819 Peter Dunrand used metal containers to apply the same principle. These containers were called cannisters, which is the origin of the word “can” (Saint Xavier University, 2000). The cause of food spoilage was affirmed in 1864 by Louis Pasteur who showed that microorganisms in foods were the cause of such contamination. He subsequently found that microbes were killed by heating and that sealed containers could be used to preserve food by preventing recontamination from atmospheric air. In 1940, a major development in the distribution and storage of foods was achieved, when low-cost home refrigerators and freezers became available. Other developments followed and included artificial drying, vacuum packaging, ionizing, radiation, and chemical preservation (Soomro, Masud, and Anwaar, 2002). A combination of techniques in which acids have played an important role have emanated as part of consequent preservation protocols for various foodstuffs (Hsiao and Siebert, 1999). One of the fundamental principles of food safety has been based on the division of foods into low-acid and high-acid categories and the according application of preservation treatments (Nakai and Siebert, 2003). Similarly to the entire food preservation process that can be traced back centuries, the use