UNDERSTANDING FOOD SAFETY

WHAT TO LOOK AT FOOD SAFETY 

When you implement an ISO 22000 food safety management system, understanding food safety is more important, in order to carry out a suitable and sufficient program based on hazard analysis and controls at points critical to food safety, it is important to have a basic understanding of food legislation and microbiology e.g. food poisoning organisms. Training is therefore an essential element in any successful food business. 

Equally important is a means to monitor how effective your ISO 22000 food safety management systems are in ensuring good hygiene practice. Any system must be frequently and appropriately reviewed to ensure that it is working properly. Any deficiencies in the system must be corrected immediately, as it may result in food poisoning.

HIGH RISK FOODS

Definition

High risk foods are foods which - Will support the growth of food poisoning bacteria (or the formation of toxins)

AND which - Are ready to eat, or have gone through most if not all steps in their preparation which might control such hazards.

Include

Foods such as - Sandwiches, pizzas, salads, hot meals.

Cooked products - Containing meat, fish, cheese etc.

Cooked products (for further heat treatment) - Pies, ready-made meals, etc.

Smoked or cured meats.

Smoked or cured fish.

Dairy based desserts.

Ripened soft or molded cheese - e.g. Brie, Danish Blue, etc.

Some types of prepared vegetable salads - including those containing fruit.

Foods labeled/described as needing to be kept at a specific temperature.

Foods bearing a use-by date.

HAZARDOUS PRACTICES

The most common causes of food poisoning outbreaks, in order of significance are:

1. The use of raw egg in uncooked or partially cooked dishes, eg: mousse, soft meringue, hollandaise sauce, etc.
2. Preparation too far in advance, e.g.: preparation of food for a large buffet, well in advance of use, without adequate refrigerated storage.
3. Storage of food at room temperature, eg: Brie cheese put out on a cheese board for more than one period up to 4 hours.
4. Inadequate cooling, eg: large joints of meat cooked in the morning and left to cool at room temperature until required for use in the evening.
5. Inadequate reheating, eg: partly cooked beef burgers only warmed through on griddle for service.
6. Contaminated processed food, eg: unpasteurized cheeses contaminated with high levels of bacteria, such as Listeria.
7. Under-cooking, eg: large poultry/boned and rolled joints cooked to a temperature of less than 75°C at the core.
8. Inadequate thawing, eg: of frozen chickens, leaving ice crystals in the core which prevent thorough cooking in the normal time.
9. Cross contamination, eg: by the handling of cooked or ready to eat foods, without having washed your hands thoroughly after handling raw meat or vegetables.

FOOD POISONING

• Food poisoning is caused by eating food which is contaminated. Most contamination is caused by bacteria.
• Sources of bacteria are people, air, raw foods, animals, insects, refuse, dust and dirt and water which is not for drinking.
• People carry bacteria in their hair, ears, nose, throat, intestines (guts) and in skin, particularly hands.
• Raw foods likely to contain bacteria are meat, poultry, fruit and vegetables (especially soil vegetables) fish, and shellfish.
• Work surfaces, knives, cloths and unwashed hands are vehicles for passing on to food.
• Chemical, including pesticides, bleach and other cleaning materials, can contaminate food if not used carefully.
• Food poisoning bacteria can make us ill and can last for days, and can kill.
• Bacteria need warmth, food, moisture and time to multiply.
• Food poisoning bacteria can only be detected in a laboratory; they do not usually affect the taste or smell of the food.

The following chart details the common food poisoning organisms.

Type of food poisoning	Where the bacteria comes from	Onset time	Symptoms
Salmonella	Raw meat, eggs, poultry, animals	6 - 72 hours	Abdominal pains, diarrhoea, fever, vomiting, dehydration
Clostridium perfringens	Raw meat, soil, excreta, insects	8 - 22 hours	Abdominal pain, diarrhoea
Clostridium botulinum (Toxin in food)	Soil, intestinal track of fish & mammals	12 – 36 hours	Difficulty swallowing, blurred & doubled vision, muscle paralyze (death common)
E. coli	Intestinal tracks of humans & animals Manured vegetables & fruit crops, water, raw milk	1 – 14 days	Varies from watery to bright red bloody diarrhoea up to 5% mortality rate
Staphylococcus aureus	Skin, nose, boils, cuts, raw milk	1 - 6 hours	Vomiting, abdominal pains, lower than normal temperature
Campylobacter	Meat, poultry, pets, unpasteurized milk	1 - 10 hours	Diarrhoea, stomach pain, high temperature, aching limbs
Listeria monocytogenes	Raw meat, soil, plant environment, water, condensation, silage	1 – 70 days	Fever, diarrhoea, septacaemia, meningitis, flu-like illness abortion, stillbirth
Vibrio sp.	Estuarine & marine waters, fish/shellfish	12 – 18 hours	Diarrhoea, Vomiting, abdominal pains, fever, dehydration
Bacillus cereus (Toxin in intestine)	Soils, dust, water, vegetation & a variety of cereals, dried foods & cereals	Type I/II 1 – 5 8 – 16 hours	Diarrhoea, Vomiting, abdominal pains

Viral Food Poisoning

Viruses can also cause food poisoning symptoms. Those commonly associated with food poisoning are Small Round Structured Viruses and Norwalk-like viruses.

Type	Where the virus comes from	Onset time	Symptoms
Norwalk-like	Food - Shellfish, vegetables, faecal, oral Aerosols - vomit particles Surfaces - door handles, toilets, wash basins	24-48 hours	Sudden vomiting, nausea, diarrhoea, abdominal pain, possibly fever

Food Allergies

This is due to the various chemicals and conditions of the food as well as it defend on the consumer which can also cause food poisoning symptoms.

Eg. Histamine

WHAT TO DO IF YOU RECEIVE AN ALLEGATION OF FOOD POISONING

You will become involved in food poisoning investigations when: 

• A food handler reports that he or she is suffering from diarrhoea and/or vomiting;
• Persons purchasing food from, or eating at, the premises complain that they have subsequently been ill.

If you are notified of a suspected case of food poisoning you must immediately act as followed.

You must then make inquiries to find out:

1. Whether any staff has been ill
2. Which food or meals were implicated and how they were handled or prepared; and
3. Whether or not any other people were affected.

If you become aware of an outbreak of food poisoning:

• Stop serving any more food and stop any more food being eaten;
• Telephone a doctor or ambulance if necessary (if people are ill on the premises);
• Retain any remaining food, cans, cartons or other forms of food packaging which may be needed to trace suspect foods;
• Inform the relevant authorities (e.g. PHI of the area)
• Inform the owners of the business
• Don’t clean up until bacteriological investigations have been carried out;
• Prepare a relevant menu list and details of food preparation, storage temperatures, methods of cooking, cooling or reheating;
• If possible, make a complete list of persons consuming the suspect meal, including their addresses;
  
• Prepare a complete list of all food handlers and other staff, especially those involved with the suspect meal. Absent staff should be included, the reason for the absence should be given
• Prepare a list of suppliers;
• Remain available on the premises to give the necessary information to the investigating officer
• When the investigation has been completed, thoroughly clean and disinfects the premises.