Organic Acids and Food Preservation .The first reported ofwkcids as antimicob nod for centuries for ve was su whic n wa Nowadays the use of sulfite as a preser- vative has been largely curtailed because of reports of adverse effects on human health,especially in steroid-dependent asthmatics,and conse- quently in preservation protocols the sulfites have been predominantly replaced by weak organic acids(Piper,1999). A contributing factor to the organic acids being of considerable value as food preservatives is that they are also food ingredients.often naturally produced by microorganisms and widely distributed in nature as normal constituents of plants or animal tissues(Gauthier.2005).Conse nes it has beco me comm lace to include iaicomta mination in and fo eds (Ricke et al,20 applied another preservative that wa oy ancie seasoning or preservati agent (Tesfaye et al,2002).The present-day definition of vinegar as a food constituent clearly hints at its being a pivotal component due to its pres ervation ability:"A liquid fit for human consumption,produced from a suitable raw material of agricultural origin,containing starch,sugars,or starch and sugars by the process of double fermentation,alcoholic and acetous,and contains a specified amount of acetic acid"(FAO/WHO,1987; Tesfaye et al.,2002). Benzoic acid is the oldest and most commonly used preservative (Barbosa-Canovas et al.,2003).In 1970 it was reported that sorbic acid had ad for e,but its safety-in-use had stablished be tensive use ng dded g list of dditives nd Ignat'ev 1970 )A st the use o a preservative reporte juice(Ferguson and Powrie,1957).Worldwide,approximately 40%of food grown for human consumption is lost to pests and microorganisms(Saint Xavier University 2000).The preservation process itself was of little public interest until a decade ago.Today it is one of the key issues addressed by every food pro- cessor(Marz,2000). 1.1.2 Toward preservative-free food Preservation of food requires the control of microorganisms throughout the food chain and p monitoring to ensure the safety and stability of shelf life (Pra etal.2005).It is said that except for tives,and n in one's own garden all food products every manu e ac s to the proce ing (Foo World 2008 there s an increa ing demand for foods without chemical preservatives(Begin and Va Calsteren,1999).Therefore,in attempting to satisfy consumer demands
2 Organic Acids and Food Preservation of weak acids as antimicrobials also has a long history. The first reported chemical preservative was sulfite which was employed for centuries for the sterilization of wine vessels. Nowadays the use of sulfite as a preservative has been largely curtailed because of reports of adverse effects on human health, especially in steroid-dependent asthmatics, and consequently in preservation protocols the sulfites have been predominantly replaced by weak organic acids (Piper, 1999). A contributing factor to the organic acids being of considerable value as food preservatives is that they are also food ingredients, often naturally produced by microorganisms and widely distributed in nature as normal constituents of plants or animal tissues (Gauthier, 2005). Consequently, in more recent times it has become commonplace to include organic acids in chemical additives to control microbial contamination in foods and feeds (Ricke et al., 2005). Vinegar is another preservative that was applied by ancient civilizations and used as a seasoning or preservative agent (Tesfaye et al., 2002). The present-day definition of vinegar as a food constituent clearly hints at its being a pivotal component due to its preservation ability: “A liquid fit for human consumption, produced from a suitable raw material of agricultural origin, containing starch, sugars, or starch and sugars by the process of double fermentation, alcoholic and acetous, and contains a specified amount of acetic acid” (FAO/WHO, 1987; Tesfaye et al., 2002). Benzoic acid is the oldest and most commonly used preservative (Barbosa-Cánovas et al., 2003). In 1970 it was reported that sorbic acid had been proposed for extensive use as a preservative, but its safety-in-use had to be established before being added to the existing list of permitted food additives (Shtenberg and Ignat’ev, 1970). A study done in 1956 reported on the use of sorbic acid as a preservative in fresh apple juice (Ferguson and Powrie, 1957). Worldwide, approximately 40% of food grown for human consumption is lost to pests and microorganisms (Saint Xavier University, 2000). The preservation process itself was of little public interest until a decade ago. Today it is one of the key issues addressed by every food processor (Marz, 2000). 1.1.2 Toward preservative-free food Preservation of food requires the control of microorganisms throughout the food chain, and proper monitoring to ensure the safety and stability of the product during its shelf life (Prange et al., 2005). It is said that except for the food grown in one’s own garden, all food products contain preservatives, and that every manufacturer adds preservatives to the food during processing (Food Additives World, 2008). However, there is an increasing demand for foods without chemical preservatives (Bégin and Van Calsteren, 1999). Therefore, in attempting to satisfy consumer demands
Chapter one:Introduction 3 for foods that are ready toeat,yet fresh-tasting,richin mins,and also minimally processe and preservec worldwide,is increasingly faced with numerous challenges(Leguerinel and Mafart,2001)and forced to respond by prioritizing the development of minimally processed food products that are at the same time nutritious and with high organoleptic quality.This places even greater strain on the general market in commercialization as minimally rocessed products &k y short shelf life,which may often be less than et al.2000) It has also omeevident that microorga s are c ntinu usly ing to survive in the presence of previously effective control methods(Ricc et al,2008).In response to safety concerns from these dilemmas,research intensified to address new techniques demanded in all steps of the pro duction and distribution chain for maintaining required food quality that will at the same time inhibit undesired microbial growth(Rico et al.,2008 Samelis et al 2002).Research has also shifted the focus to the potential tech ecology of food product s (S elis 82L2002 or as 1.2 Unrivaled advantages Organic acids have a long history of being utilized as food additives and preservatives in preventing food deterioration and extending the shelf life of perishable food ingredients,and have been demonstrated to be effective under a wide variety of food processing conditions.They have been appliedand postharvest food production and processingand cids ar ved or listed in FDA ,1 app ns fo ses in addi 10 o pres Ricke ,2003). hes on of organic acids as ac ants,flavo ing agents,pH adjusters,and even nutrients(Smulders and Greer,1998) Traditionally organic acids have,therefore,been extensively used in the food and pharmaceutical industries as preservatives,chemical intermedi- ates,and also buffer media(Bailly,2002).Much research has been devoted to the application of organic acids as preservatives because of their bac- tericidal activity and their"generally recognized as safe"(GRAS)status (Tamblyn and Conner,1997). 1.3 Economic implications:"Safer food,better business" Sustainable requres safe sustainable industrial production (Kamm and Kamm,2004).How ever,microbia contamination of foods plays a major role in economic losses to food
Chapter one: Introduction 3 for foods that are ready to eat, yet fresh-tasting, rich in nutrients and vitamins, and also minimally processed and preserved, the food industry, worldwide, is increasingly faced with numerous challenges (Leguerinel and Mafart, 2001) and forced to respond by prioritizing the development of minimally processed food products that are at the same time nutritious and with high organoleptic quality. This places even greater strain on the general market in commercialization as minimally processed products generally present a very short shelf life, which may often be less than a week (Valero et al., 2000). It has also become evident that microorganisms are continuously adapting to survive in the presence of previously effective control methods (Rico et al., 2008). In response to safety concerns from these dilemmas, research intensified to address new techniques demanded in all steps of the production and distribution chain for maintaining required food quality that will at the same time inhibit undesired microbial growth (Rico et al., 2008; Samelis et al., 2002). Research has also shifted the focus to the potential implications of new decontamination techniques on pathogen behavior as well as on the microbial ecology of food products (Samelis et al., 2002). 1.2 Unrivaled advantages Organic acids have a long history of being utilized as food additives and preservatives in preventing food deterioration and extending the shelf life of perishable food ingredients, and have been demonstrated to be effective under a wide variety of food processing conditions. They have been applied in pre- and postharvest food production and processing and various organic acids are approved or listed in FDA regulations for various technical purposes, in addition to preservation (Ricke, 2003). These include the application of organic acids as acidulants, antioxidants, flavoring agents, pH adjusters, and even nutrients (Smulders and Greer, 1998). Traditionally organic acids have, therefore, been extensively used in the food and pharmaceutical industries as preservatives, chemical intermediates, and also buffer media (Bailly, 2002). Much research has been devoted to the application of organic acids as preservatives because of their bactericidal activity, and their “generally recognized as safe” (GRAS) status (Tamblyn and Conner, 1997). 1.3 Economic implications: “Safer food, better business” Sustainable economic growth requires safe sustainable resources for industrial production (Kamm and Kamm, 2004). However, microbial contamination of foods plays a major role in economic losses to food
Organic Acids and Food Preservation pro om worldwide and hesonfo enced de nd mode e food pre control meas ety, may be affected,experiencing significant losses as a result of food spoilage as well as food poisoning (Brul et al.,2002a).Contamination of foods with pathogenic organisms may even have devastating effects on the foreign trade of a country.This was evident in the early 1990s in Peru during the initial stages of a cholera epidemic.Such economic losses may be devastat- ing even when the hazard is recognized before any consumers have been affected(Molins,Motarjemi,and Kaferstein,2001).To make matters even worse,public health officials have predicted that a number of underlying forces may make foodborne illnes ses even more of a problem in years to come.Factors such as emerging pathogens,imp orag pra ctice sum employ asing gl food ndpply and a tra ncreas se or ill have to aging and capacity to fig ses conten with in t ag Several studies have demonstrated the high cost to society of food borne illness in different countries,including the United States (1996) and Canada(1990),and there is a growing literature on the importance of reducing foodborne illness in developing countries(Motarjemi et al., 1996;Moy,Hazzard,and Kaferstein,1997;Unnevehr and Jensen,1999). From these studies the immense benefits in improving food safety are leu ka pazteuiajur Allng uaaq iou sney sigauag asau ox quaredde mpanies involved(Unnevehr and Jense 1999)Food n the control of mic ic out the food chain a and in this rega need to dict the beha mi ms and thus o get an insi ight to their cellu neral under relevan food manufacturing conditions (Bru l et al,2002a) Producer or retailer may,however,not be able to ascertain or certify the safety of foods,as a result of the wide spectrum of potential microbial contaminating agents and the hazards posed by them when encountered in food or food envi ronments(Unnevehr and Jensen,1999).It is essential that thorough risk assessment be the very first step taken by all leading food industries in optimizing the quality and safety of food products (Brul et al.,2002b). Although markets may undergo changes simultaneously with changes in the marketing environr mont ac vell as olitical frameworks direct c ac with the ind rides reliable pr ntitative inforn mation with foo s and fo y T 2002 s worth ing in particular th ge of foods and bever ages characterized by high sugar contents,lo water activ ties (by yeasts as posing a maior economic problem (Hazan,Levine
4 Organic Acids and Food Preservation processing companies worldwide and these problems are being experienced despite intensified control measures, extensive research on food safety, and modern food preservation regimes. Entire industries may be affected, experiencing significant losses as a result of food spoilage as well as food poisoning (Brul et al., 2002a). Contamination of foods with pathogenic organisms may even have devastating effects on the foreign trade of a country. This was evident in the early 1990s in Peru during the initial stages of a cholera epidemic. Such economic losses may be devastating even when the hazard is recognized before any consumers have been affected (Molins, Motarjemi, and Käferstein, 2001). To make matters even worse, public health officials have predicted that a number of underlying forces may make foodborne illnesses even more of a problem in years to come. Factors such as emerging pathogens, improper food preparation and storage practices among consumers, insufficient training of retail employees, increasing global food supply, and an increase in the number of people at risk because of aging and compromised capacity to fight foodborne illnesses will have to be contended with in the combat against the effects of microbial contamination on food safety (Medeiros et al., 2001). Several studies have demonstrated the high cost to society of foodborne illness in different countries, including the United States (1996) and Canada (1990), and there is a growing literature on the importance of reducing foodborne illness in developing countries (Motarjemi et al., 1996; Moy, Hazzard, and Käferstein, 1997; Unnevehr and Jensen, 1999). From these studies the immense benefits in improving food safety are apparent, yet these benefits have not been fully internalized by market mechanisms to reward the companies involved (Unnevehr and Jensen, 1999). Food preservation requires the control of microorganisms throughout the food chain and in this regard there is a need to predict the behavior of undesirable microorganisms and thus to get an insight to their cellular functioning under conditions generally encountered under relevant food manufacturing conditions (Brul et al., 2002a). Producers or retailers may, however, not be able to ascertain or certify the safety of foods, as a result of the wide spectrum of potential microbial contaminating agents and the hazards posed by them when encountered in food or food environments (Unnevehr and Jensen, 1999). It is essential that thorough risk assessment be the very first step taken by all leading food industries in optimizing the quality and safety of food products (Brul et al., 2002b). Although markets may undergo changes simultaneously with changes in the marketing environment as well as political frameworks, direct contact with the industry provides reliable and precise quantitative information with regard to food additives and food safety (Marz, 2002). It is worth mentioning in particular the spoilage of foods and beverages characterized by high sugar contents, low pH, and low water activities (aw) by yeasts as posing a major economic problem (Hazan, Levine
Chapter one:Introduction 5 and Abeliovich,2004).In the summer months fungal spoilage of bakery products with relatively high pH (Juneja and Thippareddi,2004)may be ineffective,as they do not have any impact on their shelf life(Marin et al., 2003).Although many of these products are carrying useless preserva- tives that could just as well be excluded from their recipes,reduction in ervatives to subinhibitory levels has be een sh or to alate myco oxin pro (Marin et and Nielsen,2004).However,it is possible that these products have to rely on a suitably low a for preservation(Marin et al.,2003). In addition to economic losses as a result of spoilage by fungal growth on bread products,production of mycotoxins and the health hazards asso- ciated with these are also a serious concern(Arroyo,Aldred,and Magan, 2005).A mycotoxin commonly associated with bread products is ochra- toxin A,the nufac pre of wh come r the r us Ochratoxin A d in wheat or in flour during the making of bread and lteinformationisava le on the effect of preservatives in bread products on ochratoxin A produc- tion by spoilage molds,especially in moderate climatic conditions(Arroyo, Aldred,and Magan,2005). The evidence is clear that measures should be taken in the food safety arena in addressing all the factors implicated in such serious economic proble aused as a re sult of mi ation of food.The ady tages of a ing of the physic ological a f preservativ systems to the food mant is envisaged among others,to improve food quality and wholesomeness through lower thermal treatment,provide possibilities for new products(mildly preserved, organic foods),save energy through better controlled processes,use less waste and cooling water,reduce the use of cleaning and disinfecting agents, and produce less waste thre ough bette is ho tha weve ·f and in control of lity is well within rea oning a particular full h,spec rom a c ns tent decline in the United States,among others,in the incidence of food transmitted salmonellosis,as a result of new developments such as the introduction of pathogen reduction steps in food processing that have been implemented in the United States by regulation(Olsen,2001;Struijk, Mossel,and Moreno Garcia,2003).Similarly improved protection of the consumer population is envisaged to be achievable in all areas of food- transmitted infections.How infection pr on the food envi ment(from raw food in particula from anim origin will require the nentation of decontamination step which shou ld be intre in production and distribution at a very specific point.This should be in
Chapter one: Introduction 5 and Abeliovich, 2004). In the summer months fungal spoilage of bakery products before their expiration date is an important concern for manufacturers. Adding to the problem is that preservatives added to bakery products with relatively high pH (Juneja and Thippareddi, 2004) may be ineffective, as they do not have any impact on their shelf life (Marín et al., 2003). Although many of these products are carrying useless preservatives that could just as well be excluded from their recipes, reduction in preservatives to subinhibitory levels has been shown to stimulate growth of fungi or to stimulate mycotoxin production (Marín et al., 2003; Suhr and Nielsen, 2004). However, it is possible that these products have to rely on a suitably low aw for preservation (Marín et al., 2003). In addition to economic losses as a result of spoilage by fungal growth on bread products, production of mycotoxins and the health hazards associated with these are also a serious concern (Arroyo, Aldred, and Magan, 2005). A mycotoxin commonly associated with bread products is ochratoxin A, the presence of which mainly comes from the wheat flour used for manufacturing. Ochratoxin A is only partly destroyed in wheat grain or in flour during the making of bread and little information is available on the effect of preservatives in bread products on ochratoxin A production by spoilage molds, especially in moderate climatic conditions (Arroyo, Aldred, and Magan, 2005). The evidence is clear that measures should be taken in the food safety arena in addressing all the factors implicated in such serious economic problems caused as a result of microbial contamination of food. The advantages of a better understanding of the physiological actions of preservative systems to the food manufacturing industry are endless. It is envisaged, among others, to improve food quality and wholesomeness through lower thermal treatment, provide possibilities for new products (mildly preserved, organic foods), save energy through better controlled processes, use less waste and cooling water, reduce the use of cleaning and disinfecting agents, and produce less waste through better process control (Brul et al., 2002a). It is, however, believed that food poisoning and in particular full control of its morbidity is well within reach, speculated from a consistent decline in the United States, among others, in the incidence of foodtransmitted salmonellosis, as a result of new developments such as the introduction of pathogen reduction steps in food processing that have been implemented in the United States by regulation (Olsen, 2001; Struijk, Mossel, and Moreno Garcia, 2003). Similarly improved protection of the consumer population is envisaged to be achievable in all areas of foodtransmitted infections. However, infection pressure on the food environment (from raw food, in particular from animal origin) will require the implementation of a decontamination step which should be introduced in production and distribution at a very specific point. This should be in
Organic Acids and Food Preservation 1.4 Legislative issues in food production In developed economies significant changes have been made to food safety regulations over the last two decades,where many countries have increased their standards for ensuring safety and quality of food intended for domestic consumption as well as for the export market.However, developing countries are reported to experience difficulties in meeting all the requirements associated with implementing high-level sanitary mea- sures involved in technical regulations and public and private standards, as well as conformity tests (Martinez and Banados,2004).Furthermore bee raging both the food and feed inc sivequality managemer in att tety, ucture a system for inspe try to consumer trust by promo ing adequ ate etal,005)Another important nformat on (Rohr actor is that continuous monitoring of proposed regulations is achievable by online government resources in updating food safety recommendations (Cabe-Sellers and Beattie,2004) Both the U.S.Food and Drug Administration(FDA)and U.S.Department of Agriculture(USDA)are involved in the provision of extensive oversight in regulating measures implemented in ensuring the safety of food.These also include compulsory and meticulous studies on safety.with regard to issues such as toxicology and pharmacokinetics,prior to the approval of spe cific i are r ulation ith ard to safe food of feed addiives autho European Uni n(E.U)legislation,o by rga nic a recom eir use is currently allowed in all lives ended as pre servatives,and th speci It is recognized that the organic acids produce no detectable abnormal res dues in meat and are,therefore,considered safe substances(Castillo et al 2004).In the United States organic acids such as lactic acid and acetic acid have GRAS status,and are approved for use.Differences in regulatory authorities are evident,particularly in the meat industry.The European Union requires strictly hygienic processing sufficient to assure product safety and does not allow any additional antimicrobial decontaminant, as it regards decontamination strategies as a means of concealing poor ary to the E.U.requireme nts,it ay be sen rally accep nitiated the the with sing proc the ohrays as a regard to meat treatment,it should be kept in mind tha even with the best and most current hygienic practices,contamination of
6 Organic Acids and Food Preservation addition to the usual hygienic practices already in place (Struijk, Mossel, and Moreno Garcia, 2003). 1.4 Legislative issues in food production In developed economies significant changes have been made to food safety regulations over the last two decades, where many countries have increased their standards for ensuring safety and quality of food intended for domestic consumption as well as for the export market. However, developing countries are reported to experience difficulties in meeting all the requirements associated with implementing high-level sanitary measures involved in technical regulations and public and private standards, as well as conformity tests (Martinez and Bañados, 2004). Furthermore, public authorities have been encouraging both the food and feed industries in developing extensive quality management systems in attempting to improve food safety, to restructure a system for inspection, and also to try to boost consumers’ trust by promoting adequate information (Rohr et al., 2005). Another important factor is that continuous monitoring of proposed regulations is achievable by online government resources in updating food safety recommendations (Cabe-Sellers and Beattie, 2004). Both the U.S. Food and Drug Administration (FDA) and U.S. Department of Agriculture (USDA) are involved in the provision of extensive oversight in regulating measures implemented in ensuring the safety of food. These also include compulsory and meticulous studies on safety, with regard to issues such as toxicology and pharmacokinetics, prior to the approval of an antimicrobial agent or preservative for use and monitoring of the food supply to ensure the agent is being used correctly (Donoghue, 2003). Of specific importance are regulations with regard to safe food production in the meat industry. In the list of feed additives authorized by European Union (E.U.) legislation, organic acids are recommended as preservatives, and their use is currently allowed in all livestock species. It is recognized that the organic acids produce no detectable abnormal residues in meat and are, therefore, considered safe substances (Castillo et al., 2004). In the United States organic acids such as lactic acid and acetic acid have GRAS status, and are approved for use. Differences in regulatory authorities are evident, particularly in the meat industry. The European Union requires strictly hygienic processing sufficient to assure product safety and does not allow any additional antimicrobial decontaminant, as it regards decontamination strategies as a means of concealing poor hygiene. Contrary to the E.U. requirements, it may be generally accepted that U.S. abattoirs initiated the incorporation of organic acid sprays as a component of the carcass dressing process. In the adaptation of E.U. regulations with regard to meat treatment, it should be kept in mind that even with the best and most current hygienic practices, contamination of