Cross Contamination

Home and Out

Cross-Contamination When an allergen is transferred from different sources e.g., kissing, hands to mouth, cooking utensils so on.

Cross-Contact a food allergen in one food touches another.

3 areas to think about at home, Food-to-food, Food-to-object, and Food-to-saliva.

Trace amounts can be fatal for some people, either being ingested or coming into contact on the skin.

Steps for cleaning effectively

You should do the following things:

  • Clean and disinfect food areas and equipment between different tasks, especially after handling raw food.
  • Clean as you go. If you spill some food, clear it up straight away and clean the surface thoroughly.
  • Use cleaning and disinfection products that are suitable for the job and follow the manufacturer’s instructions.
  • Do not let food waste build up. Dispose of food waste suitably.
  • Use a cleaning schedule to make sure that surfaces and equipment are cleaned when they need to be. It can also help to stop cleaning products being wasted or used incorrectly


(Text Source: https://www.food.gov.uk/business-guidance/cleaning-effectively-in-your-business  )

Places of cross contamination home

  1. Hands
  2. Utensils, chopping boards, baling trays, saucepans.
  3. Work surfaces
  4. Fridges, freezers, and food cupboards
  5. Steam (airborne allergen)
  6. Droplets of liquid from bubbling saucepan
  7. Flour dust
  8. Crumbs of food
  9. Cooking oils
  10. Condiments (sharing utensils, or hands not being cleaned from passing person to person)
  11. Wooden utensils or hopping boards as these absorb moisture and retains it.
  12. Tea towels
  13. Toaster – Separate toaster or tin foil on grill pan for the grill.
  14. Straws – Do not share straws.
  15. Cutlery – Do not share cutlery.
  16. Spoons – Use separate spoons when making drinks e.g., tea coffee.
  17. Cups and glasses – Do not share drinks, although the drink might be ok, the person who drank from it might had something beforehand and transferred through salvia.
  18. Spillages- Always wash your hands after a spillage.
  19. Dish Cloths – Buy dish clothes you can wash regularly and us antibacterial wipes or have separate clothes, but this can be difficult to keep track on. The safest option is to use disposable methods, such as paper towel or wipes.
  20. Containers – If using containers for storing food use separate containers from the rest of household. Buy new containers if possible and not reuse e.g., allergic to milk do not old ice cream tub. Using stickers on storages containers can help e.g., red for allergens and green for non-allergens. Make sure storage containers are airtight.
  21. Always wash hands if you are handling something that may traces of allergen or handling food for other people.
  22. Clean and sanitise work surfaces, chopping boards, hob.
  23. Have separate kitchen tools or wash and clean every tool used for preparing food with traces or allergen for other people.
  24. Use tin foil or chopping boards to prevent contamination off work surface.
  25. Food or fluids is especially important. When buying handwash but an antibacterial wash would be best but please look at the label as there could be hidden allergens e.g., nut (macadamia) or milk (cream).
  26. Cooker – If you are cooking for yourself something different from the family use different parts of the oven when possible while cooking e.g., if allergic to dairy cooking a pizza in same oven as your meal will cause airborne protein to be present around your food.
  27. Kissing – Always be aware what your partner has eaten because of transference.
  28. Rubbish – If you got the job of putting the rubbish out it comes naturally to wash your hands afterwards, but it would be dual fold now not just for germs but also allergens.
  29. Breastfeeding – If you are breastfeeding and the child has an allergy be aware of what you eat will pass onto your baby.
  30. Pets – Can transfer allergens through salvia, so pet food, tablets, medication, flea, and worm treatments would need to be checked for allergens. People with pets, or visitors should be careful with cross contamination with pet food. Either serving or dogs licking your hands or face can cause cross contamination. Pet food can include the follow allergens (but not limited to) Gluten (cereals), milk, peanuts (dog treats), eggs, fish.
  31. Preparing food – If more than one person involved in cooking a meal ask all people to wash their hand and be aware of your allergies.
  32. Smaller portions – Remember to keep label with smaller portions or leftovers for future reference.
  33. Toothpaste – Be aware toothpaste can have allergens in e.g., Recaldent is milk-derived, also Casein phosphopeptides are derived from milk casein (a milk protein).
  34. Aprons – If you wear a cloth apron then wash regularly.
  35. Oven gloves – Please remember oven gloves will have food residue on, either have separate oven gloves or wash oven gloves regularly.
  36. Microwave- Clean microwave after every use even if it does not look dirty, the steam and cooking can cause airborne allergens.
  37. Washing up liquids – check the ingredients this could have something in you are allergic to.
  38. Blenders.
  39. BBQs
  40. Dishwashers, rinse washing up before going into machine.
  41. If taking products out of packaging, label the containers.
  42. Have a separate tin opener.
  43. Have a set area for eating, so allergens do not contaminate other parts of the household.
  44. If you are keeping an allergy free home and depending on your severity of your allergy, ask your guests politely if it is okay for them to wash their hands.
  45. Deep fryers, oil contamination from previous foods that are not allergen free.
  46. When cleaning surfaces use a commercial cleaning product.
  47. Allergens can withstand heating and drying.
  48. If a mistake is made, then discard the item and start over.
  49. Keep allergens away from children, if this is not possible, then keep allergens out of reach.
  50. If allergens are loose, store allergen free foods above allergen foods. This makes sure no allergens can fall onto non-allergen foods.
  51. Do not store similar foods together.

Cross contamination while out

  1. Salad bars
  2. Parties and buffets – Even if there are allergen free food for you if it has not been kept separate or prepared separate then it can be contaminated either by the preparer or the guests by picking up and putting down foods.
  3. Shopping – Take disposable gloves depending on how severe your allergy is. Hand gels are good, but most will not clear nuts or traces of peanuts.
  4. Sharing – Do eat off someone else plate, you cannot be sure that the food has been checked for allergens unlike yours.
  5. Cups and glasses – Do not share drinks, although the drink might be ok, the person who drank from it might had something beforehand and transferred through salvia.
  6. Food – Do not pick an allergen out of food as this will not be safe.
  7. Napkins and Kitchen towel – Do not share these.
  8. Shops and loose products.
  9. Bakeries.
  10. Use own bag for non-allergen foods.
  11. Restaurants read reviews and check out before eating at a restaurant.
  12. Deli foods.
  13. Do not be afraid to double-check with your server about food preparation to be safe.
  14. Eating establishments Has there been a last-minute recipe change or ingredient substitution?
  15. Carry handwipes so can be used if washing hands facility available, then wash hands when possible.
  16. If meal comes out with allergen on, send it back and ask for a whole new meal.
  17. Self-service ice cream bars.
  18. Fast food takeaways
  19. School cafeterias.
  20. Never try a food, even a bite that may contain the allergen you are allergic to as this could put your health at serious risk.
  21. Deep fryers, oil contamination from previous foods that are not allergen free.
  22. Tables and chairs ask for the table to be cleaned using a commercial cleaning product.
  23. Ice cream parlours, in store bakeries, and delicatessens foods are usually unlabelled, always ask for ingredients. Also be mindful of cross contamination, same utensils being used e.g., cutting knives on sandwiches, same trays, and food touching each other.
  24. Magazines giving free food gifts.

This list is not exhaustive if you have a reaction and you have counted out eating an allergen, then keep a diary of what you were doing every time you have a reaction. Put as much detail as you can on each entry as this will help for you to see pattern where the cross contamination is happening.

Cleaning Effectively FSA

Information given is to be used with individual’s discretion they are responsible for their safety; this information is not to be on its own solely and always seek medical advice.

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