Please enable JavaScript.
Coggle requires JavaScript to display documents.
Topic 1 (page 1): Food bio-deterioration and methods of preservation -…
Topic 1 (page 1): Food bio-deterioration and methods of preservation
Definition
The degradation of food by microbiological agents, either directly or indirectly through products of their metabolism, is known as biodeterioration. In order to provide safe and healthful packaged foods, this chapter examines how the agents of food biodeterioration function and the commercial techniques available to combat them.
Food bio-deterioration agents
Non enzyme
Non-enzymic browning
Progressive browning and the development of off-flavours.
Microbe
Microorganism
Psychrophilic
Psychrotrophic
Mesophilic
Thermophilic
Thermoduric
Bacteria
B. subtilis
Breaks down complex carbohydrates into simple sugars that can be absorbed through the cell membrane.
B. amyloliquefaciens
B. licheniformis
Pathogenic bacteria
Listeria monocytogenes,
Produces a toxin that attacks the nervous
system.
Escherichia coli
Staphylococcus aureus
Bacillus cereus
Camplylobacter
C. botulinum
Beneficial bacteria
Lactic acid
Used to beneficial effect in fermentation and preservation processes to extend the shelf life of certain foods.
Fungi
Penicilin
Produces powerful lipases and proteases.
Key agents in the ripening of blue cheeses and Camembert.
Oospora lactis
Occurs on the surfaces of cultured milk as a white velvety
coating.
Enzyme
Pectinesterase
Causing a softening of the tissues as the cell wall materials are broken down.
Enzyme ihibitor
Lead to enhanced browning reactions that cause discolouration during cooking.
Polyphenol oxidase- Presence of air oxidises phenolic constituents to indole quinone polymers.
references:
Gould, G. (1995). Biodeterioration of foods and an overview of preservation in the food and dairy industries. International Biodeterioration &Amp; Biodegradation, 36(3–4), 267–277.
https://doi.org/10.1016/0964-8305(95)00101-8
Coles, R., & Kirwan, M. (Eds.). (2011b). Food and Beverage Packaging Technology. Food Biodeterioration and Methods of Preservation.
https://doi.org/10.1002/9781444392180
Bio deterioration reactions
Enzymatic
Polyphenoloxidase- Causing enzymic browning.
Lipoxygenass- Ccausing oxidative rancidity.
Lipase- Causing lipolytic rancidity.
Protease- Causing gelation and flavour and texture changes.
Microbial
Growth of spoilage organism- Causing quality deterioration.
Growth of toxigenic organisms- Causing food poisoning.
Presence of infectious organisms- Causing food poisoning.
Chemical
Oxidation which causing oxidative rancidity.
Loss of colour.
Maillard reactions.
Physical
Moisture movement.
Dry and toughening of texture.
Hydration and softening of texture.
Aggregation.