Cleaning and sanitation have always been critical aspects of food safety, as both help to prevent cross-contamination and ensure food is safe. Now more than ever we need to ensure that we create more robust cleaning programmes to prevent the spread of the highly infectious COVID-19 in our food establishments and homes. However, we must note that if these functions are carried out improperly, food can be further contaminated.

The contact surfaces for all food must be cleaned and sanitised. This includes utensils, knives, tables, cutting boards, conveyor belts, bins, aprons, floors, walls and many others, including our hands! But before going on a cleaning frenzy we need to ensure we select the correct chemicals or else we pose the risk of harming ourselves and consumers.

Just a reminder that cleaning and sanitising are two different processes and achieve different outcomes. Cleaning is a process to remove visible dirt, organic matter, chemical residue from surfaces or objects. Cleaning doesn’t eliminate microorganisms but lowers their numbers. Sanitising is the process by which clean surfaces or objects undergo a treatment that kills microorganisms or reduces them to a safe level. Both cleaning and sanitation go hand in hand; sanitising won’t usually work effectively without first going thorough cleaning. Additionally effective cleaning and sanitising begin with selecting the right product.

Before selecting your cleaning and sanitation products you need to consider the following:

• Ensure products are approved for the intended use in your industry. This is important as products used should remove dirt and kill microorganisms but not contaminate food. With the current high demand for cleaning agents you may be tempted to just buy anything that is available; however, you should ask your supplier for a safety data sheet (SDS) and verify that your cleaning products are food safe.

• Factors such as product attributes (eg odour and colour), storage and mixing requirements for water pH, water hardness and temperature, presence of organic matter should be considered when choosing the right product as these factors can affect how the agents respond to your equipment and product and even to yourself and employees.

• Not all sanitisers are equal. You need to ensure that the sanitiser you use is suitable for the job. For example, inexpensive chlorine, while it will kill most microorganisms and is effective at low temperatures, may corrode metal and weaken rubber. It is also unstable at high temperatures and not effective with organic matter. On the other hand, quaternary ammonium compounds have non-corrosive residual activity if not rinsed and are less affected by organic materials. However, it is ineffective for certain microorganisms and inactivated by most detergents and hard water. Another agent is iodine, which may kill most microorganisms and is less affected by organic materials but may stain plastic and porous materials and is inactivated by temperatures above 49 ºC.

• Different surface materials have different reactions to different cleaners and sanitisers; some products such as caustic alkaline or acidic cleaners may be effective in removing dirt and food residue but can also be corrosive to softer metals such as aluminum or lower grades of steel.

• It is very important to practise due diligence in selecting products that are safe for use on food surfaces or equipment. We don’t want to choose products that cause the surface, or equipment that is being cleaned and sanitised, to deteriorate, as this will make them more difficult to keep them clean. Additionally, we want to reduce sources of cross-contamination, not add to them. Choose cleaning and sanitation agents that are effective and get the job done with minimal potential for this.