Archive for category Food Handling

FACT: Your kitchen can breed  millions of bacteria in just 24hrs

bad bacteria

Many studies have investigated bacterial contamination in the domestic kitchen and many cases of food poisoning originate in the domestic environment and can be associated with improper food handling and ineffective cleaning by consumers. These practices could lead to the introduction and spread of bacterial contamination in the kitchen and if not subsequently removed could present an infection risk.

There is no legislation and very little training to inform domestic food preparation practices so the risk at home is much higher in contrast to commercial premises. The following research and findings are intended to inform you on the ways to prevent bacterial contamination in your own kitchen.

FINDINGS – Results showed that;

1. contamination levels varied during the day, peaking after meal preparation and generally falling overnight.
2. There was also indirect evidence of cross contamination, particularly from hands to other surfaces. Sites such as the refrigerator handle, kettle handle and taps, which generally only come into contact with hands, show increases in the levels of contamination recorded.
3. Levels of microbiological contamination were lower in vegetarian than non-vegetarian households.
4. A variety of data showed that non-food preparation activities also take place in the kitchen. These could also introduce bacterial contamination into the kitchen and facilitate their spread.
5. Microbial contaminants varied, the most common being Enterobacteriaceae although Salmonella, Campylobacter, E. coli and Staphylococcus aureus were also frequently recovered.

THE FACTS- studies noted;

1. an increase in sites in the kitchen with microbial infection after preparation of a chicken meal.
2. that an increase in the number of hygiene violations during the preparation of a meal was matched with an increase in the number of contaminated sites in the kitchen.  *Potential microbial risks  sites in the kitchen,are kitchen  sinks, taps, work surfaces and dishcloths.
3. Bacterial contaminants are introduced to the kitchen in a variety of ways and once attached to surfaces, particularly in biofilms, are difficult to remove.
4. Dishcloths act as both habitats and vectors for bacterial contaminants. Warmth, moisture and food debris allow bacterial counts to reach high levels rapidly  and these cloths are able to transfer contaminants to other sites.
5. Hands have been shown to transfer bacteria from foods to various sites in the kitchen and,
6. several studies have shown a wide range of kitchen sites to be cross-contaminated by food preparation.

Why dishwashing liquid alone does not do the job

cleaning agents

Cleaning was shown to reduce bacterial contamination, but only when anti-microbial agents were applied using a strict protocol. Where cleaning was carried out simply with detergent and hot water using a prescribed method, 15.4 per cent sites remained contaminated compared to 17.3 per cent sites after cleaning where no method was specified. After disinfecting with 5,000 ppm hypochlorite for five minutes using a specified method, pathogens were isolated from just 2.3 per cent of sample sites.

In a domestic kitchen,  it is likely that one chopping board is used for a variety of purposes: it therefore poses a high risk of cross contamination, particularly if the board is used for chopping raw meat or poultry. A study  showed that bacteria were readily transferred to chopping boards during preparation of meat and then contaminated vegetables prepared on the same board. It is unlikely that typical cleaning procedures that do not involve disinfectant will remove these contaminants .

clean well

A study  demonstrated how a number of kitchen sites including surfaces, chopping board, and the handles of taps, kettle and refrigerator become contaminated during the preparation of a meal from raw chicken. Unless cleaning is thorough, bacterial contamination may not be reduced  and may even be increased via contaminated cloths  or hands. Contaminants may then grow potentially reaching infectious dose levels and, in the presence of moisture and food debris, surviving to contaminate the next food preparation event.

clean as you go

CONCLUSION– The implications of these results are;

1. that the most important time for cleaning in the kitchen is immediately after food has been prepared, with attention focusing on high risk areas such as the work surface, chopping board, taps and other hand contact surfaces.
2. Clean areas and utensils thoroughly with detergents and hot water and follow up with industrial grade disinfectants.
3. If you could afford it, buy separate color coded chopping boards and use it separately depending on the type of food being handled.

Sample Chopping board color codes

1. RED for raw meats.
2. YELLOW for poultry, don’t use for anything else.
3. GREEN for veggies and fruits.
4. BLUE for fish and other seafoods.
5. BROWN for cooked meats.
6. WHITE for bread and pastries.

Summarized from: British Food Journal -: Consumer food safety Volume 107 Number 7 2005 ,Bacterial contamination of domestic kitchens over a 24-hour period, I.W. Haysom and A.K. Sharp