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Prepared by: Shaimaa, Dalya, and Fenek
Food pollution
Introduction
The term contamination of food means the food or water contain substance that makes it unfit for human or animal consumption, whether toxic chemicals or micro-organisms harmful or food contaminated with radioactive materials lethal, which may cause injury to the consumer disease, which is the best known diseases food poisoning.
Food contaminationThere are three ways which food can be contaminated:
•Physical;
•Chemical;
•Bacterial.
Physical contamination-Pollutants reach the food during growth and harvest,
like stone, soil and minerals, insects and their remnants.
-Pollutants reach the food during the manufacturing process and deliberation, the remnants of glass, bone, metal, wood and electrical wiring, grease, rust and paint residue .
-Pollutants reach the food during the process of packaging and distribution, such as insects, thread, hair and stones and minerals.
Chemical contamination:
- chemicals from the farm
- cleaning product used in the processing plant when packaging food
-fly spray used in the kitchen when preparing
- Care must be taken at each stage of food production to prevent chemical contamination.
Bacterial contamination: -Autolysis: self destruction, caused
by enzymes present in the food
-Microbial spoilage : caused by the growth of bacteria, yeasts and moulds.
Desirable food changesAutolysis and micro bacterial changes are sometimes desirable (and are not referred to as spoilage), for example enzymes cause fruit to ripen .
Here are some positive micro bacterial changes below.
Bacteria in yoghurt production.
Mould in some cheeses, e.g. Stilton.
Yeast in bread production.