Domestic Kitchen Safety is extremely important. Accidents occurring at home are a very high cause of serious injuries and may be more disruptive and disorienting than those equivalent injuries occurring in the work place. Why? Because we just don't expect it in the safety of our homes and although busy, tends to be quieter with  predictable periods of chaos but otherwise calm and controlled. An accident  can cause  confusion.

When accidents occur at home reaction time should be quick but not panicked. Panic just adds more confusion and delays to the process of doing the best we can and appropriately. Often there is pain, surprise and fright. These three elements generally are not dangerous by themselves but responses by the body to a situation. Pain itself does not cause injury, but panicking to control the pain can lead to unsafe behaviour and subsequent further injury. Surprise is instantaneous and fright can usually be controlled by competent reassurance. The carer should be calm, reactive and ideally informed. They are best to be in control. If a victim is in physiological shock that is they are generally unconscious or heading that way, then you need to act definitely and quickly.

The most important thing to remember and to control is the safety factor. Remove the elements that caused the mishap. If it was a burn make sure the source of the heat is turned off or turned away from the place of the treatment. If it was caused by broken glass or a blade, then remove the blade or shattered glass from the area of treatment. If it was an electrical incident, then switch off the power to the appliance and remove the appliance  from the power receptacle.



Don't be a sausage. Be informed on Safety and First Aid
( You may well  be a true life saver with these skills)


Injuries occurring during cooking: Burns and cuts.

Burns: Occur in the cooking phase of food preparation.

The specific burns encountered may be due to naked flame, hot surfaces, steam or hot oil. Occasionally there are electrical burns. Remember to make the situation safe for yourself and any victim before assessing or treating them. This really is the most important aspect of First Aid.

Irrespective of the cause the damage done is identical and the first aid treatment is the same. The higher the heat the more damage can be done.

Naked flame burns generally come from gas cooking. The best way is to get into the habit of turning off the gas at the same time you finish cooking. If there's a two or multi-stepped cooking process it is worthwhile turning off the gas in between each cooking process. The re-igniting of the gas takes a second, the heat is instantaneous and the risk of accidental burning is minimal. Gas installations should be carried out by trained service people. Gas is one area where there seems to be a delay in poor workmanship and accidents. It is usually as simple as a miss-matched fitting but it is likely to show up in time and cause an accident. Inspection of connecting hoses and regulators for damage is a good habit also. If something is not right then at the earliest convenient time call a gas plumber  to have the problem rectified.

Hot surfaces occur around the site of the heat and the cooking utensils used. The spot support structures over a gas ring will be hot obviously and few people would presume to touch this without checking first. Cooking implements are less likely to be presumed hot if they are not with the cooking items. So a ladle which may have been used for cooking the contents in a pot may be put down on a cold surface and mistakenly picked up not by the handle but by a hot part and can burn.

Steam issuing from a pot with a lid covering is as hot as boiling water but in fact it may have more heat and can burn terrifically extremely quickly. The steam on a dry hot day can be fairly invisible in low light situations. An arm reaching across a pot even with some covering can receive a very bad burn if it comes too close to the steam. Another cause of steam burn is when pouring off excess boiling water. The steam that issues when a pot is turned out into a sink or whatever has a much greater surface area so that a lot more steam issues up when this happens. This generally is a low level burn but can cause a reaction that then may cause a much more serious burn such as dropping the pot and splashing the boiling contents. Stumbling and an injury not related to a burn but still debilitating. Steam is often an overlooked risk.

Hot oil causes extremely severe burns. Temperatures are typically 180ºC (350F). Spilled hot oil is a nightmare-ish scenario. Never transfer hot oil using a one handled pot. There is such lack of control that the slightest glitch can cause a spill. The most sensible people would allow all hot oil to cool to room temperature before doing anything with it, one handle or two.

Spattering oil can be caused by small eruptions such as cumin seeds splattering in the oil. This is often used as a test for checking appropriate oil temperature for frying. It's a good test but be wary. The trick here is to keep well back so that the tiny oil globules can't hit you on the skin. The second most common reason is water in or on the food. Typically vegetables that have been peeled and washed then placed into frying oil are the causes of fairly marked splattering of oil. It's important to pat dry washed vegetables with a cloth or paper towels and inspect them before placing them into the oil. It's also a good habit to use tongs to place the food object into the oil rather than fingers.

The third cause of oil burns is fire. The fire can start by over-heating of oil generally on a naked flame or gas burner. There are usually warning signs before ignition including the generation of smoke and increased aroma from the superheated  oil. For this reason it's important that you keep an eye on the heated oil at all times. Sometimes there is a fire in an oil pan and unfortunately a person has poured water onto the flames. The oil will spatter out explosively in this situation and much of it will be alight. Never pour water onto hot  oil. The first thing that should be done is to attempt to smother the flames with a lid preferably and turning off the heat source as well. The best way to smother  flames beyond the pot is with a fire blanket. The extinguisher is the third level of flame control. Be informed on how to use your dry chemical or CO2 extinguisher. There are safety consideration in using this tool.

Electrical burns are caused by current arcing across the skin with heat generation and is always due to an electrical short circuit fault. Turn off the power to the appliance and remove the power cord from the power outlet. Be most careful not to touch the victim if they are still in contact with the electrical supply until turning off the electrical supply. You are at grave risk of being electrocuted if you do so.



Cuts: Occur generally in preparative phases of cooking and often by blades, typically for two reasons.

1. Loss of concentration and not focusing on the job at hand.
Don't allow a distraction to jeopardise safety. It is better to stop the activity for the time of an interruption then resume when the situation allows.

2. Using sharp tools that are not matched or maintained for the job.
If the job requires cutting hard foods such as galangal then it really is important to have a sharp implement for this. You really don't want to put excessive force onto a dull blade and then inevitably some loss of control when it "gives". If the edge was sharp before the job, the pressure required is greatly reduced and the loss of control not a factor. Either learn to sharpen blades or have a contractor do this for you periodically. Generally speaking dull blades cause more injuries than sharp blades!!

3. Preparing food with potentially dangerous equipment is dangerous while taking drugs which slow down reaction times and awareness. Excess alcohol is most definitely contra-indicated during food preparation.

4. For people who may have some  attention deficit due to medication, vascular disease or some neurological type illnesses for your safety and well being maybe you should ask yourself if you are safe doing the cooking tasks at hand? It's a really hard thing to say I know and maybe the answer is very unpalatable. I don't know your reaction to this possibility but can sympathise with such a predicament. One possible solution is to work with some one else or a group of people who can all support and teach each other new aspects in a safe environment  with reassurance.




Cuts caused by broken glass.

This is also a common occurrence at home. Glass breaks on impact and when there is a sudden big change in temperature.

Dropping glass is something that can be difficult to prevent but there are some high risk and preventable precautions.

Don't pick up hot contents in a glass vessel. You will drop it as a reaction.

Glass surfaces and water cause a lack of friction and glass easily slips in wet hands. This one is easy. Dry your hands and dry the glass object.

Don't place boiling hot foods into a cool glass vessel. The expansion of the glass can fracture it.



Fire Safety

Kitchens are best served by dry fire extinguishers. Water based extinguishers are dangerous in cooking areas, for two reasons: Oil and water don't mix and in fact the  addition of water onto a burning oil fire can cause a splash of burning oil so rapidly spreading the fire. The second aspect is that kitchens tend to have many electrical appliances with the obvious risk of electrical injury when water is added to the situation. 

The easy availability of a fire blanket is an exceptionally sensible precaution. If your kitchen has a single line of access and the food prep and cooking area are central, then it is highly recommended that you invest in two dry chemical extinguishers and two fire blankets, one set for each side of the hob. Dry chemical extinguishers are an effective flame extinguisher if you know how to use them. Please read the information provided for effective deployment of these two life and property saving facilities.

If the Fire Blanket has been used in a situation then it's really important to replace it with a new Blanket. This item is only useful as a single use safety aid.

If the Extinguisher has been used then this must be taken to the service/advisory centre for re-charging and testing before being presumed to be useful subsequently.


The work area.

The area of preparation should be cleaned and uncluttered. You should have unobstructed access to flowing water.

There should be a safe supply of electricity and the electrical appliances should be safe. If you have a portable island bench then have overhead power outlets installed. Don't have trailing extension leads across the floor. It's very dangerous.

No frayed or perished electrical cords, non-double insulated appliances must be earthed and/or protected by a functional RCD circuit.

Power outlets and electrical appliances should not be within a meter of a faucet and never within the area beneath a faucet. (This is generally controlled by regulations)

Power cords must not be trailing in water or oil on the work surface.

Shoes should be worn when using electrical appliances. Shoes act as insulator in the case of an electrical fault and secondly they generally offer some grip in a sudden slippery situation.

Make sure you have dry hands when connecting/disconnecting an appliance to the electrical supply outlet.

Power cords should not be draped across thoroughfare spaces and they should not cross a work prep area such as a cutting board.

If an electrical incident has occurred then please do not resume use of the appliance and their fitting until it has been thoroughly re-inspected. If it fails inspection and cannot be safely repaired, then discard the appliance and make sure any other person cannot use it, no matter how dear and dear it is. Life is far more valuable!



Spills are hazardous!

If you spill food or water on the floor then it is important to clean and dry this area with a mop or cloth immediately.
If you spill oil or cooking grease onto the floor. Firstly let it cool if it was hot. Then wipe it up with absorbent material such as paper or a cloth. The next thing to do is to wash the area with a detergent to completely remove any oily residue. Rinse and dry. This is important.



Burns! First Aid

I apologise for teaching your grandmother how to suck eggs and I do think that most of us are sensible and careful. Accidents on the other hand happen unexpectedly and an accident caused by disorganisation or by fluke momentary incident is likely to cause damage and personal injury to some extent, irrespective of the cause. We are working with really high energies when cooking Asian food. Often high flux gas rings, hot oil in an exposed area and steam. Any of these can injure quickly.

A good space for cooking Asian should be uncluttered, ventilated with clear lines of sight and thoroughfare to the running cold water. All obstacles from the cooking area to the tap (faucet) should be inspected and cleared.

In the case of a burn of any origin to the skin, move immediately, without delay, to the running cold water and place the affected body part under the running cold water and keep it there for 5 minutes or longer. If you do this really quickly you will likely reduce the damage caused by the heat on the exposed tissues and those tissues in close proximity to the directly burned and it will reduce the pain. You may be tempted to remove your hand or foot or face from the cold running water because the pain may be disappearing. Don't. Maintain the immersion. Don't apply ice to the burned area as this may cause frostbite.

Don't  remove any burned clothing that maybe melted around the skin and adhering. Inspect the burns. If the burns look significant and there is pain then you may choose to seek  some medical treatment for pain control if nothing else. If they are reasonably extensive, red, blistered and painful then it is likely to be second degree burns. The area of second degree burning is taken as an indicator of severity as well as the site. If the second-degree burn is no larger than 3 inches (7.5 centimeters) in diameter, treat it as a minor burn. If the burned area is larger or if the burn is on the hands, feet, face, groin or buttocks, or over a major joint, treat it as a major burn and get medical help immediately.

If the burn looks severe and there is little pain then please go straight to medical services. This could be a third degree burn and can confuse the victim as the pain isn't the indicator. The nerves may have  been damaged and so the pain receptors aren't there. This needs to be assessed and treated  urgently.

If the burn is painful but minimal as you have probably experienced many times throughout your cooking life and scouting or sneaking cigarettes and backfiring matches or lighters, then you may elect to simply ignore or take some OTC analgesics. It's of no clinical benefit to dress these burns except to prevent the inadvertent knocking and the 1000 degree stabs of pain caused by this. This sensitivity often subsides quickly.

Generally speaking do not dress any wounds with ointments or tinctures. You can loosely cover the burn area with sterile gauze but not the cotton flock type. There is little significant risk of infection at this stage and you may in fact be adding more damage to the injury by treating with tinctures and ointments. Do not dress the wound with butter or petroleum grease (Vaseline). These are quite difficult to remove and need to be removed for any medical treatment. Some burns ointments are effective local anesthetics for very minor burns but can cause further tissue damage if the burn is of greater severity. eg: many of these contain chemicals such as picric acid, phenol, alcohol all are neurotoxic and biocidal. Antiseptic solutions such as straight Dettol, Povidone and 70% alcohol can and probably will destroy some good and exposed tissue.

If the burns require medical treatment by ambulance and or hospital then please don't administer any pain killer medicines. Pain can be distressing to the observer but it won't harm the victim. The ambulance officers will have standing orders and telephone communications with medical personnel if pain control is required. This will probably be administered by injection or inhalation gas. If the victim requires surgery then giving anything by mouth can possibly delay treatment.

The initial  treatment for burns is the same irrespective of the cause of the burn.



First Aid for Cuts

If the accident is due to broken glass, quickly check to see if there is any glass in the wound. If there is a relatively large shard(s), DO NOT REMOVE THE GLASS. Place a gauze pad over the shard drape dressings  each side of the protruding shard. Then go to an emergency treatment centre.
If the cut is unobstructed and minor,  with a clean cloth pat dry the area and place gauze pad over the cut and wrap dressings over the wound with enough pressure to stop bleeding.
If the cut is large then pressure is the first line of treatment. This is best done with a clean towel folded to cover the area then pressure applied over the cut. If this is a large cut or if bleeding is difficult to control, you will need to get to an emergency treatment centre. It is probably best to call an ambulance in this case. It's important to maintain the pressure on the cut the whole time while waiting for assistance. Once assistance arrives then let them takeover and follow any instructions they may have.



First on the scene

If you are the first to appear and there looks to have been a serious accident  then first and most importantly look to see if there are any safety hazards: Fire, boiling liquids, broken glass evidence of electrical accident. Please keep calm your safety depends on this as well as that of the victim.

You need to make the area safe by dealing with these quickly and effectively before you assist any injured person. (You must not jeopardise your own safety in this situation because it is quite likely that you could become a victim of the same cause and then there are two casualties needing help)

If there is fire, extinguish the flames with coverings such as towels or blankets. Turn off the gas or power to any cooking device. Make sure that pot handles are turned inwards to prevent accidental spilling of contents. Unplug any electrical appliance. Sweep away any broken glass into a safe corner. Remove all chairs and other things.

Assess the injuries as best you can. Check that the victim is conscious. Make sure that you can safely lay them on the floor if they feel faint or in fact do faint. 

If they are unconscious lay them on the floor. It doesn't have to be on their side just flat on the floor. Check for cuts if there is any broken glass,  pottery or blades around. Attend to severe cuts with towels and pressure. You need to call medical assistance here.

Wait until assistance arrives while keeping focused on the victim's state of consciousness and bleeding.



Securement of wounds (sutures and glues).
{Not inherently important at the time of injury but a burning question most often}

The decision to secure a wound in many situations is partly a medical decision and partly a personal decision. The best answer to this is to discuss your options with your doctor.

The difference between glue and sutures: There doesn't appear to be any difference in outcome. There is little difference in discomfort during the procedure but there may be a perception that sutures hurt more. There really is little evidence to support this in minor situations. Once again discuss this with your doctor.



Food Prep Hygiene.

This is an area that can drive people crazy. OH&S doesn't need to be fully implemented in a household. But the principles are very reasonable and do help in preventing food spoiling and contamination.

Clean any surface prior to food preparation. Wash your hands. Always use clean implements and dishes.
Prepare meat first of all and if not cooked immediately place aside in the fridge or on the bench if it will be a short time. If the non-refrigerated safety margin time is 1 hour then remember that the one hour is the total accumulated time that the meat is out of the refrigerator. For example if the meat is initially out for 30 minutes while you are preparing it and related processes then you place it in the fridge for two hours. Then you may organise your ingredients for cooking and this may take 20 minutes. At this stage you may need to prepare a sauce or some other ingredient which may take you another 15 minutes. Now you are beyond the safety margin and the meat is considered unsafe for direct consumption. You now need to make sure you cook this meat well before consuming it. A rare style is not appropriate for meat out of the safety margin before cooking.

Wash the meat dishes and implements. Clean the work bench immediately. This is possibly the single most important cleaning requirement. Bacteria are at the highest numbers immediately following  preparing meat. Wash your hands again.

Wash all vegetables in potable running tap water. If the water is not potable rinse the produce under the running water to remove the bulk of the potential contamination then rinse again by pouring bottled or cooled boiled water over the produce to rinse away any original water. Most studies trialing various cleaning agents for vegetables and fruit haven't delivered anything as hoped. In fact there have been some negative effects. The use of high salt content, hypochlorite, lemon juice, vinegar all have failed as a reliable disinfectant. The best cleaning is with fresh running water.

If the water you use is contaminated with bacteria boiling will kill the bugs if it is allowed to boil for long enough. This is considered as 1 minute at sea level adding an extra two minutes for each mile of altitude (1600 metres). So boiling vegetables typically for 3  minutes or greater is a safe practice.



Frozen Food Safety

Recommended freezer temperatures vary depending on the term of storage and whether or not the freezer will be used for freezing foods from ambient temperatures. The all inclusive recommendation is for a freezer to maintain a temperature at -18oC (0F). Food is considered safe and palatable  stored at this temperature for up to three months.

Frozen foods, particularly meats should be thawed in the refrigerator. If this is followed the thawed meat can be refrozen. (Ref:



Refrigerator Storage

The temperature of your fridge compartment must be between 0oC and 4oC (ie 32F and 40F) {At temperatures less than 0oC (32F) contents may begin to freeze. This may cause a change in the physical nature of the food and an increased rate of deterioration when thawed}
Freezer temperatures should be at or below  -18oC (0F)

Loading your fridge from a trip to the supermarket should be done systematically. Unwrap excess wrappers of meat parcels. Make sure meats are sealed in plastic wrap. Wash your hands between each item of meat to minimise cross contamination at this level.  Take note of the use by dates or the sell by dates and recommendations for usage. Write the date of freezing on each packet of goods.

After loading the meats again wash your hands. Load the rest of the items in a systematic and relatively open piles to allow air to cool the food quickly and completely. After chilling it is OK to re-pack the piles of foods into more condensed piles for better use of space.

Modern refrigerators usually have pre-moulded sections or shelves in the door. Typically eggs, milk and other dairy produce are earmarked for this area.  Unfortunately refrigerator doors are often not well insulated and some of the door spaces investigated, have shown unacceptable temperatures in this region even when the body compartment was within safe limits. Thus presume the door is an unsafe area for milk and eggs. Both of these should be stored in the main body of the fridge.  (You may like to check the door temperatures with an appropriate thermometer over a few days. If it's within specification then of course it is safe to use the door as supplied for storage. The door is OK for butter/margarine and cheeses, sauces and other relatively stable items. In very hot conditions at least, do not use the door for milk and egg storage.

Meat should be stored at the bottom of your refrigerator and preferably in the meat drawer.  This prevents downward cross contamination. Thawing of meats should be done in the refrigerator within the body of the fridge but the frozen meat should be contained within a resealable plastic bag and then placed on a tray or plate. This will ensure that if there is any leakage it won't potentially contaminate other foods below that level in the fridge. One of the bad bugs here may be listeria which can be quite nasty and can cause miscarriage in pregnancy at any stage of gestation. Listeria will affect any of any age moderately severely. There are quite a few other nasty bugs that are noticed with meats.

Perishable foods purchased in stores should be eaten by the use by date or within a specified period of the sell by date. Unfrozen foods pre-packaged may be frozen but please mark on them the number of days to expiry post defrost.

Spills should be cleaned immediately and this is particularly important if the liquids of the meat are spilled. Meat is the number one potential infectious food item.

Food drawers should be cleaned periodically and if you shop once a week then it's good to clean the drawers once a week.

Defrosting non-auto defrost fridges. Ice accumulation will reduce the efficiency of the refrigerator and can even take parts of the fridge above the safety temperature. Most fridges have a defrost button and some means of collecting any condensate from the defrost. It's important to empty this defrost regularly if its collected within the body of the cabinet of the fridge during the process particularly if the fridge is well iced.  The reason being is that this defrost may also be contaminated if there was any spill in or on the freezer compartment of such a fridge. The smaller the volume managed at a time, the less likelihood of spilling the condensate again. As with all routine processes it's ideal if you can set a schedule for defrosting say once a fortnight and this will prevent any major ice build up and temperature problems. There is no need to force defrost the fridge. Allowing the fridge to defrost under it's own system is the best way to manage this. This will keep refrigerated items cold and safe during the process and the auto-start will kick in when the temperature gets above the set limit.  It's always a good thing to have an appropriate  thermometer in the fridge to check the operating temperature and the defrosting temperature.

The running temperature of the fridge should be set and checked periodically it's most important to measure the temperature  on the first shelves of the body of the fridge and make your adjustments based on your temperature readings there. Finally there may be variations over the year of the fridge temperature. For this reason also it's a good practice to measure the operating temperature and make adjustments as needed.

I don't think that any of these guidelines are burdensome and the level of protection offered is great. No-one following these guidelines will cause cross contamination and you will be sure of the most efficient and safe refrigerator storage of perishable produce.




What is Botulism?

Botulism is an illness caused by the toxin produced by the bacteria Clostridium botulinum. The toxin is extremely potent and arguably one of the most potent poisons known. 500 gm or 1 lb has been calculated as being enough toxin to kill half the population of the world.
Botulism toxin causes paralysis and damage of nerve-muscle joins. This can cause arrest of breathing. It generally requires victims to be placed on a respirator and for as long as three months until there is generation of new tissue.


In this photomicrograph you can actually see the spores being the little nodules of clear area within the rods or bacillae and some spores without the growing bacillae


Where is the bacteria found?

There are a few subtypes of the bacteria but in short it can be found in the soil on most of the world.

How does the poison get to people?

In humans the most common way it seems is by spore contamination of the initial foodstuffs that have been stored in an anaerobic situation. That is without oxygen. In fact the organism can grow with up to 2 % oxygen content. It also  prefers a neutral pH that is a pH around 7.This most commonly occurs in preserved foods. The spores germinate and the bacteria grows, producing the toxin. If the toxin containing food is then consumed, without heat inactivation, the active toxin will also be ingested by the victim and the onset of the illness can be observed within a few hours to within a couple of days.
There have been reported cases of wound infection and botulism but rarer still.
There have been reports of babies being victims of botulism caused by honey. This is some risk until babies move from milk to solids. This is due to lack of gastric acid preventing growth of the bacteria in the babies gastro-intestinal tract.
Finally there have been very few cases reported of adults been affected by botulism when there has been no contact with affected food and no wound injury. The offered explanation is an ingested bacteria or spore that has somehow activated and got past the defence mechanisms and grown producing the toxin and causing the illness.

Is it a risk?


Is it likely to be a problem?


Is it preventable?


Is it easy to heat sterilise the bacterium?

The bacteria in growth phase are quite easy to destroy by heat . It's their spore state where they are extremely resistant to sterilisation by heat. The organism is known as thermophilic and can withstand high temperatures for an extended period. The spores are the resting phase or ungerminated bacteria. The spores need a temperature of 160oC for 2 hours to be sure of eradication or 15 minutes at 121oC and 15 psi steam.  These conditions are unsuitable for many foods causing damage to flavour and texture. Examples of this would be infused oils, because the heat would destroy the flavours associated with the original ingredients.
The spores will germinate in appropriate conditions and this can happen even at refrigerated temperatures although at a slower rate. That's why the recommendation of fridge storage for these foods is 10 days maximum

What foods has botulism been associated with?

Pretty well most foods but particularly meats, fish, and flavoured oils such as Chillie Oil and Garlic oil, to name a few. Our concern particularly is with oils. Oils have very low oxygen levels and the contents tend to be at neutral pH. Meats, vegetables and fish would have to be stored without oxygen and the spores activated. (Typically improperly container preserved foods)

So how does one prevent botulism?

There are a number of strategies.

  • Autoclaving or steam sterilisation at 121oC for 15 minutes. (This is the same as using a pressure cooker for home sterilisation)

  • The use of some inhibitor chemicals in the processing of some foods. (This is really restricted to commercial processes)

  • Short term storage only of foods at risk: 10 days refrigerated is deemed to be an acceptable time for storage. Frozen foods are safe and can be cooked and consumed within a reasonable time to be free of the risk.

  • The toxin is very sensitive to heat and is completely destroyed in 10 minutes by holding at 85oC. This is different to the resistance of the spores. One strategy is to heat treat the food at 85oC making sure that the food content itself reaches 85oC and then hold that 85oC for a period of 10 minutes before serving. This is a guaranteed safe outcome.

  • Discarding malformed cans of food particularly if they are billowing out or produce a rush of gas on opening.

  • Don't perform home preserving without knowledge and the correct equipment.  It's better to contact a bona-fide home preserving company and read as much as is appropriate on the safe practice of home food preserving. Ask questions of professional people in the field of this area.

  • Commercial products of at risk domestic preserves are a safer option because the standards and options that the accredited manufacturing companies have is greater than that available for domestic use.



Rice Food Poisoning.

Bacillus cereus is a micro organism, a bacterium, which may cause acute illness being vomiting and or diarrhoea.
The bacterium is killed by heating such as the process for rice cooking but there's another aspect. The bacteria can produce spores that are not destroyed by heating at the temperature of boiling water. So a possible scenario is that contaminated rice with the bacillus cereus spores is cooked. It is left over-night at room temperature and then a batch of fried rice is made. In that period of overnight the spores have germinated and produced what is called vegetative bacteria that as a result of their growth may produce toxins. The three significant toxins in the brew can cause humans to be sick. Two of these can cause severe diarrhoea and abdominal pain. The other called 'cereulide' can cause vomiting. The symptoms of vomiting are generally quick onset being as short as 60 minutes after eating. The diarrhoea toxin tends to be delayed 18 hours.

Unfortunately the spores are not killed by boiling water and neither is the chemical toxin produced by the vegetative bacteria that causes vomiting, destroyed. The diarrhoeal toxins seems to be destroyed by heat. The bacteria themselves are killed but the damage has been done. As mentioned, the vomiting toxin, cereulide, is also very resistant to heat damage so that after re-cooking in the case of fried rice for example, the toxin is still in the food and still able to cause havoc to the diner and it does.

How to prevent the food poisoning:

You have a few options here.
  • You can keep the rice held at a temperature of >65ºC (149F) and this will prevent the spores from germinating and the bacteria from growing.
  • You can refrigerate the cooked rice within four hours of cooking. This temperature prevents the growth of the bacteria and production of toxins. Refrigerated rice is considered safe for a storage period of up to 3 days.
  • You can eat cooked rice within four hours of cooking and then dispose of the left-overs.

Keeping cooked rice for extended periods of time is a very common method for rice preparation and subsequent eating. There are also rice dishes that are cooked and served for days after preparation in traditional recipes such as the SE Asian rice in banana leaf deserts and confections. Obviously not everyone gets sick.

This leads to the next question of:

How likely is it to get sick from stored rice after cooking?
There were 14 outbreaks and 691 reported cases in the US between 1993 and 1997. This is quite a low number and is likely to be an underestimate of the true number of cases. Illness caused by this organism is not required to be reported to the CDC. This number still suggests quite a low incidence.
It would be great to know of the incidence of cases in countries of Asia where rice is eaten everyday by everyone  :)
Other surveys have suggested that the organism bacillus cereus is the cause of 2-5% of food caused illness.

Do people build a tolerance to the toxins produced by the bacillus cereus?
The answer to this seems to be: 'No'. The toxin that causes vomiting, cereulide, seems also to kill the immunocytes, the very first level of resistance to an attack. Because of the killing of the immunocytes there is no population of lymhphocytes established to produce a specific antibody and thus it is unlikely that subsequent contact would produce an increased resistance by an individual to this toxin. In other words you are not likely to build up a resistance to Rice Food Poisoning

Does the bacillus cereus cause any other disease?
It does.
It has been associated with some cases of chronic skin infections and keratitis, an eye infection.
It may cause septicaemia but the national US incidence is only 2 reported cases a year. Not a worrying incidence.

If you are very cautious then I think that you should refrigerate your rice within 4 hours of cooking or keep it held on the warm cycle of your rice cooker >65ºC (149F) for up to 24 hours.

The diagnosis of bacillus cereus caused illness is not likely to be a definitive diagnosis, in other words your doctor is not likely to tell you for sure that your illness was caused by bacillus cereus or Rice Food Poisoning, as a proven cause, but may say that it is one of the possibilities. The diagnostic methods are highly technical and are specialised, therefore costly, being reserved to groups that are doing research on this topic. The cost benefit of including this testing in people with acute diarrhoea and/or vomiting likely to be caused by food probably isn't seen as important for treating affected people. This is because the treatment is supportive and the symptoms are self limiting, meaning that people recover within a reasonable period of time without a specific intervention. This doesn't mean that modern medicine doesn't care about this as it certainly does care about any who are acutely ill. The information provided by knowing that it was caused by rice is of no real benefit in the majority of cases. This would be different in the case of an outbreak or a lot of cases of this illness and would be considered if this were to happen.



© All Rights Reserved. Used with kind permission of Peter Edin

This image is  like the botulism micrograph in that the bacteria are rod shaped, (bacillus), and has the bright spores inside many of the  bacillae.

This organism grows in the presence of oxygen. The spores are heat resistant. The toxin responsible for vomiting is also heat resistant.

Google Analytics Alternative