Classification Incidental Adulteration

Food Standard and Quality Control

Lesson 25 : Food Adulteration

Classification Incidental Adulteration

Unintentional or incidental adulteration

InciĀ­dental contamination occurs usually due to ignorance, negligence or lack of proper facilities. Contamination of foods with deleterious substances such as toxins, insecticides, pathogenic bacteria and fungi and other harmful micro organisms during production, storage and handling will affect the health of the consumer.

The Argaemone mexicana is frequently found growing in brassica fields and if proper care is not taken during cultivation its seeds get mixed with those of brassica and the oil expressed contains also argemone oil. Its presence in edible mustard oil is injurious to health and might result into outbreaks of epidemic dropsy (extreme edema) .

The most common incidental adulterants are pesticides. DDT, malathion and pyrethrum residues might be present on the plant products more than the safe limits. The maximum permissible residue limits for DDT and malathion is 3 ppm and for pyrethrum it is 10 ppm. '

These toxic chemicals are absorbed by the small intestine when ingested and adhere to the fatty tissues-the toxins usually pile up in the fatty tissues of such vital organs as the thyroid, heart, kidney, liver, mammary gland and testes and damage these organs. These are easily transferred through placenta to foetus and breast milk to infant. The presence of these chemicals in children will lead to crippling and also inhibits normal growth.

Contamination with harmful microorganisms may occur at the time of cultivation itself, if the vegetables are grown on sewage. These foods if consumed in the raw state may cause food poisoning. Generally these are destroyed during cooking or processing of food. However some microorganisms, both due to heat resistance or inadequate heat processing may still survive and contaminate the food.

Several studies have indicated that food grains, legumes and oil seeds when stored in humid atmosphere are infected by pathogenic fungus which can cause serious illness. The pathogenic microorganisms that commonly contaminate foods and responsible for causing serious illnesses are shown below.

List of common pathogens that cause serious illness in human beings:

Pathogenic Organisms Foods Commonly involved Ill effects and diseases
Bacillus cereus Cereal products Nausea, vomiting, abdominal pain
Clostridium botulinum toxins Defectively processed meat and fish Botulism (muscular) paralysis, death due to respiratory failure.
Clostridium perfringens (welchii) Defectively processed precooked meat Nausea, abdominal pain and diarrhea.
Salmonella Defectively processed meat, fish and egg products, raw vegetables grown on sewage. Salmonellosis (vomiting diarrhea and fever).
Shigella Sonnei Foods kept exposed for sale in unhygienic surroundings. Bacillary dysentery.
Staphylococcus aureus Foods kept exposed for sale in unhygienic surroundings. Increased salivation, vomiting, abdominal pain and diarrhea.
Staphylococcus pyogenes Foods kept exposed for sale in unhygienic surroundings. Scarlet fever, septic sore throat.
Aspergillus flavus (aflatoxin) Liver damage and cancer.
Claviceps Perpurea (Ergot) Rye and pearl millet infested with ergot. Ergotism (burning sensation in extremities peripheral gangrene.
Fusarium Sporotrichiodies Cereals and millets infected with fusarium Alimentary toxic aleukia.
Penicillium islandicum Rice Liver damage.
Trichinella spiralis Pork and pork products Nausea, vomiting, diarrhea, colic and muscular pains (trichionosis).
Ascaris lumbricoides Raw vegetables grown on sewage farms Ascariasis
Entamoeba histilytica. Raw vegetables grown on sewage farms Amoebic dysentery.
Ancylostoma duodenale (Hookworm) Raw vegetables grown on sewage farms Epigastric pain, loss of blood, anaemia.
Last modified: Tuesday, 21 February 2012, 10:34 AM