Sunday, April 22, 2007

Facts About Foodborne Illnesses

What Are Foodborne Illnesses?

Foodborne illnesses are caused by consuming contaminated foods or beverages. Different microbes and pathogens can contaminate foods, in addition to other contaminants such as poisonous chemicals or harmful substances from food-production plants, equipment or food-handling workers.

There are many kinds of foodborne illnesses which are usually caused by different bacteria or other pathogens on food. They can affect a person by displaying many flu-like symptoms such as nausea, vomiting, diarrhoea or fever. Pathogens refers to bacteria that cause disease or an illness. When certain pathogens enter food, they can cause serious foodborne illnesses.

Which Are Common Foodborne Illnesses?

There are a few commonly recognised foodborne illnesses caused by bacteria and pathogens such as Campylobacter, Salmonella, Clostridium botulinum, Listeria monocytogenes and Escherichia coli.

Campylobacter jejuni and Campylobacter coli are bacterial pathogens that can cause Campylobacteriosis, with symptoms of fever, severe abdominal pain, nausea and diarrhoea. Typical foods which can be affected are: chicken, raw milk, pork and drinking water. Sources of transmission include eating raw/undercooked poultry, cross-contamination with raw poultry meat, contamination with untreated water and contact with live animals and birds.

Salmonella is a bacterium that can be found in many domestic and wild animals like poultry, pigs, cattles and home pets. Ingestion of infected food sources can cause Salmonellosis with symptoms of fever, headache, nausea, vomiting and abdominal pain. Typical foods which can be affected are: raw and undercooked eggs, meat and poultry as well as raw milk. Sources of transmission include consumption of infected food sources, cross-contamination owing to poor hygiene (e.g. faeces of an infected animal/person) and prolonged storage at temperatures at which the organism can grow.

Clostridium botulinum
Clostridium botulinum is a bacterial toxin that causes Botulism. Its symptoms are vomiting, abdominal pain, fatigue, muscle weakness, blurred vision which can eventually lead to paralysis and respiratory or heart failure. Typical foods which can be affected are: vegetables, condiments, fish and meat products. Honey is also a mode of transmission in infant Botulism. Sources of transmission include ingestion of the toxin in foods, raw or under-processed foods stored in ideal conditions for growth of the organism and faulty preservation of food (e.g. canning, fermentation, curing).

Listeria monocytogenes
Listeria monocytogenes is a psychrotrophic bacteria that causes Listeriosis. Symptoms of this foodborne illness include flu-like symptoms such as fever, headache and occasionally gastrointestinal symptoms. Typical foods which can be affected are: raw milk products, meat-based paste, raw vegetables and soft cheese. Sources of transmission include contamination from soil and infected animals or drinking under-pasteurised milk.

Escherichia coli (E. coli)
Escherichia coli is bacterial pathogen and are msotly found in the gatrointestinal tract of humans and other warm-blooded animals. However, consumption of food or water contaminated with faecal material can cause E.coli infections. Its symptoms are varying to the many strains of E.coli. Vomiting, diarrhoea, cramps, fever and dysentery can occur ranging to severe and bloody diarrhoea and painful abdominal cramps. In some cases, a complication called hemolytic uremic syndrome (HUS) which includes anaemia, profuse bleeding and kidney failure can occur several weeks after the intial symptoms. Typical foods which can be affected are: minced meat, raw milk and vegetables. Sources of transmission include from huamn fecal contamination via water ot secondary tranmission from person-to-person.


World Health Organisation. (2000). A Focus For Health : Foodborne Disease. Geneva: World Health Organisation

Dean O. Cliver, Ph.D. (1999). Eating Safely: Avoiding Foodborne Illnesses. Caifornia, Davis: American Council on Science and Health.

Wednesday, April 4, 2007

What Is Food Safety?

Food safety involves safe handling, preparation and storage of food in order to keep it safe for consumption and free from food-borne bacteria which can cause serious illnesses. Hygiene is especially important to maintain a fair level of food safety as unhygienic conditions or practices can easily introduce bacteria to food, pathogens ones at worse. Pathogenic food-borne bacteria, like Salmonella, Listeria monocytogenes and Clostridium botulinum can easily cause serious food-borne illnesses in humans.

Food manufacturers and food-handling employees should practice good personal hygiene when in contact with food and other important steps in the food preparation area, such as Hazard Analysis and Crtical Control Points (HACCP) to promote food safety and reponsible preparation of food to be served to consumers.


1. Clean: Wash hands and food prepartion surfaces often

Bacteria can spread from soiled hands to foods. It is important to wash hands properly and wear gloves for a preventive measure when preparing food.

2. Separate: Don't cross-contaminate

Bacteria can pass from one food to another, for example, from raw foods to cooked foods. Kitchen utensils and equipment, such as chopping boards should be washed and cleaned regularly expecially after raw food have been in contact with these surfaces.

3. Cook: Cook to proper temperatures

High temperatures of different cooking methods ensures that enzymes that cause food spoilage are denatured and harmful microorganisms that can cause food-borne illnesses in the raw foods are killed, allowing food to be safe for consumption.

4. Chill: Refrigerate promptly

Foods that are refrigerated quickly have a lesser period of time for microbes to fester as a low storage temperature would inactivate harmful bacteria and prevent them from mulitplying.


Task from HFLA Template

Qn : Some microbes that are most likely to thrive in food are Salmonella, Listeria monocytogenes, Bacillus cereus, Coliforms and yeasts and moulds.

Research :

For pound cakes, these are likely food-borne bacteria:

Salmonella is a pathogenic bacteria that can be passed onto humans from consumption of contaminated food. It is identified as one of the microbes likely to grow on our research product, pound cake as it can cause serious food-borne illnesses, especially when eggs are eaten raw or undercooked. Eggs are a major ingredient used in the baking of Mom's Pound Cake, hence, Salmonella is a possible risk if eggs used in the cake batter are not sufficiently cooked.

Coliforms are also food-borne bacteria, which could be found in food not properly prepared in optimal hygienic conditions. Coliforms such as E.coli are commonly found in humans' intestinal tract, which can be passed onto food if food preparation workers do not practice good personal hygiene. Therefore, the presence of Coliforms can be an indicator of the sanitary quality of foodstuffs. Preparation of the pound cakes would involve manufacturers coming into contact with raw ingredients, as well as in packing the final product. Gloves should be worn and good personal hygiene of all the workers should be observed at all times.

Bacillus Cereus
Bacillus cereus is also another food-borne bacteria responsible for foodborne illnesses. B. cereus are facultatively aerobic spore-forming bacteria, which allows them to produce or form spores when food is undercooked. If the food is also improperly refrigerated, the spores are likely to mulitply further, rendering the food unsafe for consumption. The pound cake has to be blast-frozen and kept in an ideal temperature of -18°C. If the storage temperature is not kept in a suitable range or the process of blast-freezing does not allow the internal temperature of the pound cake to reach a similar storage temperature, B. cereus is likely to fester.

Yeasts and Molds
Yeasts and molds are common causes of spoilage in food and they can most likely grow in moist environments. Some yeasts are psychrophilic, which mean that they can thrive in very low temperatures at which the frozen pound cakes are kept. They can also fester in conditions of high sugar content and pound cakes are a likely source with sugar as an ingredient. Molds tend to multiply in high moisture conditions and also when in contact with air. They can also be introduced from flour, present as an another major ingredient in the making of pound cakes. Hence, yeasts and molds are a highly likely source of spoilage in pound cakes.