Food Preservatives

by Russell, Nicholas J.; Gould, G. W.

• ISBN13: 9780306477362
• ISBN10: 030647736X
• Edition: 2nd
• Format: Hardcover
• Copyright: 2003-08-01
• Publisher: Plenum Pub Corp

Summary

For centuries man has treated food to prolong its edible life, and nowadays both traditional and modern preservatives are used widely to ensure the satisfactory maintenance of quality and safety of foods. There continues to be increased public concern about the use of food additives, including preservatives, resulting from a perception that some of them may have deleterious effects on health. However, as eating habits have changed with an emphasis on what has been popularly termed a 'healthy diet', there is at the same time a concern that reduction in preservative usage could lead to loss of safety and protection from food poisoning. While some preservatives are coming under increasing regulatory pressure others, particularly more natural ones, are receiving increased attention and gaining in importance and acceptability. This book supports the continued safe and effective use of preservatives within these current constraints. It therefore gives detailed information on the practical use of the major antimicrobial preservatives. Uniquely, it couples this with current understanding of their modes of action, at the levels of cellular physiology and biochemistry, in such a way as to provide a sound scientific basis for their efficacy. Such an approach also encourages the future logical development and use of preservatives.

Table of Contents

Major, new, and emerging food-poisoning and food-spoilage microorganisms	1	(14)
G.W. Gould
N.J. Russell
Introduction	1	(1)
Food-poisoning microorganisms	2	(5)
Salmonella	2	(2)
Campylobacter	4	(1)
Listeria	4	(1)
Yersinia	4	(1)
Vibrio	5	(1)
Aeromonas	5	(1)
Escherichia	5	(1)
Staphylococcus	6	(1)
Clostridium botulinum	6	(1)
Clostridium perfringens	7	(1)
Bacillus cereus	7	(1)
Food-spoilage microorganisms	7	(4)
Gram-negative, catalase-positive, oxidase-positive rods	8	(1)
Gram-negative, catalase-positive, oxidase-negative rods	9	(1)
Gram-positive, catalase-positive, non-sporing rods	9	(1)
Gram-positive, catalase-positive cocci	9	(1)
Gram-positive, catalase-negative, non-sporing rods and cocci	10	(1)
Gram-positive, catalase-positive, spore-forming rods	10	(1)
Gram-positive, catalase-negative, spore-forming rods	10	(1)
Yeasts and molds	11	(1)
Conclusions	11	(3)
References	11	(3)
Major preservation technologies	14	(11)
N.J. Russell
G.W. Gould
Introduction	14	(1)
Basis of food preservation	14	(1)
Major of food preservation techniques	15	(7)
Low temperature	15	(2)
Reduction in water activity	17	(1)
Vacuum and modified-atmosphere packaging	18	(1)
Acidification	19	(1)
Use of preservatives	20	(1)
Compartmentalization	20	(1)
Heat	21	(1)
Physical preservation technologies	21	(1)
Conclusions	22	(3)
References	22	(3)
Acidulants and low pH	25	(23)
I. R. Booth
M. Stratford
Introduction	25	(1)
Direct action of pH and acids on microorganisms	25	(4)
Lowering the external pH by addition of strong inorganic acids	25	(2)
Lipophilic weak acids that lower the cytoplasmic pH	27	(1)
Potentiation of the effects of weak-acid preservatives by low pH	28	(1)
Other direct actions by weak acids	29	(1)
Acid as an indirect stress: consequences of lowering cytoplasmic pH	29	(4)
Buffering capacity of the cytoplasm	29	(1)
Proton removal mechanisms	29	(2)
Cytoplasmic pH and central metabolism	31	(1)
Low cytoplasmic pH and oxidative stress	32	(1)
Changes in cytoplasmic pH that aid survival	32	(1)
Acids in foods: the antimicrobial effectiveness of different acids	33	(2)
The relationship of pH to growth and survival	35	(1)
External pH: growth and survival	35	(1)
Cytoplasmic pH: growth and survival	36	(1)
Acid-resistant food pathogens and spoilage microorganisms	36	(3)
Escherichia coli O157	37	(1)
Salmonellae spp.	38	(1)
Weak-acid preservative-resistant yeasts	38	(1)
Adaptation to low pH	39	(3)
Conclusions	42	(6)
References	42	(6)
Organic acids and esters	48	(37)
M. Stratford
T. Eklund
Summary	48	(1)
Introduction	48	(1)
The use of organic acids and esters in foods	49	(3)
Natural food components	49	(3)
Food additives	52	(1)
Chemical properties of organic acids and esters	52	(2)
The pKa value	52	(1)
Log Poct, the partition coefficient	53	(1)
Solubility	53	(1)
Volatility	53	(1)
General mechanisms of antimicrobial action	54	(4)
Acidification of the external medium	54	(1)
Classical ``weak-acid theory,'' acidification of the cytoplasm	55	(1)
Action on membranes: lipids and proteins	56	(1)
Metal ion chelation	56	(2)
Action on metabolism	58	(1)
Organic acids as antimicrobial agents	58	(12)
Small fatty acids - formic, acetic, propionic, butyric, and benzoic acids	58	(5)
Medium-small fatty acids - valeric, hexanoic, heptanoic, and sorbic acids	63	(1)
Medium-large fatty acids - octanoic, nonanoic, decanoic, undecanoic, and lauric acids	64	(4)
Citric acid	68	(1)
Lactic acid	69	(1)
Esters as antimicrobial agents	70	(4)
Simple esters	70	(1)
Glycerol and sucrose esters	70	(1)
Phenol esters - parabens	71	(3)
Adaptation and resistance by microorganisms	74	(2)
Conclusions	76	(9)
References	76	(9)
Sulfite	85	(17)
G.W. Gould
N.J. Russell
Introduction	85	(1)
Uses in foods	85	(3)
Mode of action	88	(9)
Chemistry of sulfite	88	(1)
Reactions of sulfite	89	(2)
Uptake of sulfite by microorganisms	91	(2)
Metabolism of sulfite by microorganisms	93	(2)
Antimicrobial action of sulfite	95	(2)
Postscript	97	(5)
References	98	(4)
Nitrite	102	(17)
N. Benjamin
J. Collins
Introduction	102	(1)
Sources of nitrates and nitrites	103	(1)
Health concerns with sodium nitrite in cured meats	103	(1)
Nitrate and nitrite metabolism	104	(6)
Nitrate metabolism by bacteria and plants	104	(1)
Nitrate and nitrite metabolism in man	105	(1)
Nitrate and nitrite in the diet	106	(1)
Metabolism of nitrate in humans	106	(1)
Oral nitrate reduction	107	(1)
Acidification of nitrite - production of NO in the mouth and stomach	107	(1)
NO synthesis from the skin	108	(1)
Importance of nitrogen oxides in host defense	109	(1)
Mechanisms of NO-mediated microbial killing	109	(1)
Antimicrobial activity of acidified nitrite	109	(1)
N-nitroso compound formation in cured meats	110	(1)
N-nitroso compounds and human health	110	(1)
Effect of additives and ingredients on nitrosamine formation	110	(1)
Regulation of nitrite in cured meats	111	(1)
Nitrite regulation in the United Kingdom	111	(1)
Nitrite regulation in the United States	111	(1)
Nitrite regulation in other countries	111	(1)
Functions of nitrite in meat curing	112	(3)
Effect of added nitrite on C. botulinum	112	(1)
Effect of added nitrite on spoilage microbes	113	(1)
Effect of added nitrite on other pathogenic microbes	113	(1)
Nitrites as coloring fixatives in cured meats	113	(1)
Flavor development with nitrite cured meats	114	(1)
Conclusions	115	(4)
References	115	(4)
Solutes and low water activity	119	(27)
N.J. Russell
L. Leistner
G.W. Gould
Introduction	119	(1)
Influence of water activity on microorganisms	119	(3)
Multiplication	120	(1)
Metabolic activity and toxin production	120	(1)
Resistance	121	(1)
Survival	122	(1)
Foods	122	(3)
Adjustment	123	(1)
Products	123	(1)
Traditional foods	124	(1)
Novel foods	124	(1)
Microbial response to low water activity: basic mechanisms	125	(12)
Accumulation of compatible solutes	126	(3)
Osmoregulation of compatible solute uptake	129	(3)
Molecular properties of compatible solutes	132	(1)
Gram-negative bacteria and osmoregulation of the periplasm	132	(2)
Peptidoglycan structure, turgor pressure, and water movements	134	(2)
Membrane lipid changes in response to low aw	136	(1)
Combined factors	137	(9)
Hurdle effect and hurdle technology	138	(1)
Applications of hurdle technology	138	(1)
References	139	(7)
Bacteriocins -- Nisin	146	(33)
T. Abee
J. Delves-Broughton
Introduction	146	(1)
Definition of nisin activity and nisin potency	147	(1)
Methods of assay	148	(1)
Stability and solubility	148	(1)
Antimicrobial spectrum	149	(1)
Mode of action	150	(2)
Factors affecting nisin action	152	(3)
Intrinsic food factors	152	(1)
Effect of temperature	153	(1)
Resistance to nisin	153	(2)
Toxicological studies	155	(1)
Practical applications of nisin and food preservation	155	(11)
Natural cheese	155	(2)
Pasteurized processed cheese and processed cheese products	157	(1)
Pasteurized milk and other dairy products	158	(1)
Canned vegetables	159	(1)
Meat	159	(3)
Fish and shellfish	162	(1)
Alcoholic beverages	162	(2)
Miscellaneous applications	164	(1)
New target organisms	164	(1)
Future prospects for the use of nisin in foods	165	(1)
Genetics and maturation pathway of nisin	166	(2)
Protein engineering of nisin	168	(11)
References	169	(10)
Natamycin	179	(17)
J. Stark
H.S. Tan
Introduction	179	(1)
Physical and chemical properties	179	(2)
Mechanism of action	181	(1)
Sensitivity of fungi to natamycin	182	(3)
Inhibition of mycotoxin formation by natamycin	185	(1)
Applications of natamycin	186	(6)
Surface treatment	186	(1)
Cheese	187	(2)
Sausages	189	(2)
Other applications	191	(1)
Regulatory food status of natamycin	192	(4)
General considerations	192	(1)
Regulatory food status in different countries	192	(1)
Conclusion	193	(1)
References	193	(3)
Ethanol as a food preservative	196	(22)
P. Kalathenos
N.J. Russell
Introduction	196	(2)
Use of ethanol in food preservation	198	(3)
Preservation by the deliberate addition of ethanol	198	(1)
Preservation by ethanol sachets in the head space of packaged food	198	(2)
Is ethanol really a vapor-phase inhibitor?	200	(1)
Anti-staling effects	201	(1)
Indirect use of ethanol in food technology	201	(1)
Synergy of ethanol and other antimicrobials	202	(1)
Antimicrobial mode of action	203	(9)
Defining ethanol tolerance of microorganisms	203	(1)
Ethanol and water activity	204	(2)
Pleiotropic effects of ethanol	206	(1)
Ethanol action on membranes	207	(4)
Are membranes the primary target for ethanol?	211	(1)
Legal considerations	212	(6)
References	212	(6)
Modified atmospheres and vacuum packaging	218	(22)
A.R. Davies
Introduction	218	(1)
Gases used and their modes of action	219	(4)
Biological effects	219	(4)
Oxygen limitation or carbon dioxide inhibition?	223	(1)
Factors other than packaging affecting spoilage development	223	(2)
Initial contamination	224	(1)
Temperature	224	(1)
Product composition	224	(1)
Non-microbial product deterioration	225	(1)
Color	225	(1)
Odor and flavor	225	(1)
Tenderness and texture	226	(1)
Exudate	226	(1)
Packaging materials	226	(2)
Packaging machines	228	(1)
Microbial ecology	229	(3)
Meat	229	(1)
Fish	230	(1)
Processed meats	231	(1)
Microbial safety	232	(1)
Developments in MAP	233	(2)
Predictive microbiology	233	(1)
Combination treatments	234	(1)
Intelligent packaging	235	(1)
Conclusions	235	(5)
Acknowledgments	236	(1)
References	236	(4)
Surface preservation for fruits and vegetables	240	(22)
I.J. Seymour
Introduction	240	(1)
Factors affecting the quality of fruits and vegetables	241	(4)
Enzymic browning	242	(1)
Respiration	242	(1)
Ethylene production	243	(1)
Microorganisms	243	(1)
Storage temperature	244	(1)
Surface washing of fruits and vegetables	245	(8)
Chlorine	246	(4)
Organic acids	250	(1)
Ozone	250	(2)
Chlorine dioxide	252	(1)
Hydrogen peroxide	252	(1)
Trisodium phosphate	253	(1)
Surfactants	253	(1)
Surface preservatives for fruits and vegetables	253	(4)
Edible films and coatings	254	(1)
Chemical control of post-harvest disease	254	(1)
Ionizing radiation	255	(1)
Light	255	(1)
Biological control	256	(1)
Natural antimicrobials in fresh produce	256	(1)
Summary	257	(5)
References	257	(5)
Naturally occurring antimicrobial systems	262	(29)
S. Roller
R. G. Board
Introduction	262	(1)
A systems approach to food preservation	262	(5)
Agents that damage microbial cell walls: lysozyme and other hydrolytic enzymes	267	(9)
Lysozyme	267	(6)
Chitinases and other hydrolytic enzymes	273	(3)
Agents that perturb the physiology of microbial membranes: lactoperoxidase	276	(2)
Agents that impair microbial metabolism: iron chelators and avidin	278	(2)
Agents having a generalized and ill-defined role: plant extracts and phenolics	280	(3)
Augmentation of existing antimicrobial systems: fruits and vegetables	282	(1)
Accentuation of the rate of autosterilization of a commodity	283	(1)
Future prospects	283	(8)
Acknowledgments	284	(1)
References	284	(7)
Starter and protective cultures	291	(30)
W.H. Holzapfel
U. Schillinger
R. Geisen
F.-K. Lucke
Introduction	291	(1)
Bacterial starters and protective cultures	291	(15)
General aspects, definitions, and new concepts for food preservation	291	(2)
Antagonism and mechanisms of action	293	(5)
Food commodities	298	(8)
Fungi in food processing	306	(4)
General aspects, relevant species, and mycotoxins	306	(2)
Mechanisms of antagonism	308	(1)
Application of fungi in food commodities	309	(1)
Future prospects and genetic optimization	310	(11)
References	312	(9)
Legislative aspects	321	(27)
J. Smith
Introduction	321	(1)
Role of preservatives	321	(1)
Acetic acid	321	(1)
Benzoic acid	321	(1)
Alkyl esters of p-hydroxybenzoic acid (p-hydroxybenzoates, parabens)	321	(1)
Sorbic acid	322	(1)
Propionic acid	322	(1)
Sulfur dioxide and its salts	322	(1)
Nitrites	322	(1)
Antibiotics	322	(1)
Diphenyl	322	(1)
o-Phenylphenol	322	(1)
Thiabendazole (2-(4-thiazolyl) benzimdazole)	322	(1)
Legislation of preservatives	322	(23)
EC legislation	323	(11)
Codex Alimentarius	334	(3)
Preservatives legislation - the international scene	337	(8)
Future trends in preservatives legislation	345	(3)
References	346	(2)
Food preservatives -- future prospects	348	(23)
F.M. Rombouts
S.H.W. Notermans
T. Abee
Introduction	348	(2)
Primary production	348	(1)
Food processing and preservation	348	(1)
International trade	349	(1)
Consumer preferences	350	(1)
Stress response and virulence	350	(9)
Cold shock	351	(1)
pH and acid stress	352	(4)
Osmotic stress	356	(1)
High hydrostatic pressure	357	(1)
Heat shock	358	(1)
Risk analysis	359	(6)
The need for risk analysis	359	(1)
The risk analytical concept	359	(1)
Risk assessment	360	(2)
Risk management	362	(1)
Risk evaluation	362	(1)
Risk management option assessment	362	(2)
Implementation	364	(1)
Some specific preservative issues	365	(6)
Low-molecular-weight compounds	365	(1)
Cultures and bacteriocins	365	(1)
Enzymes	366	(1)
Concluding remarks	366	(1)
References	367	(4)
Index	371