At last summer has arrived. It’s time to eat al fresco — but remember as the temperatures rise, so do the cases of food poisoning. The risk of salmonella in chicken may be greatly reduced now, but campylobacter, which is one of the main causes of diarrhoea in adults, is becoming extremely common because this warm weather provides the perfect environment for the bacteria to flourish.

I don’t want to be a party-pooper, but it’s worth remembering the way bacteria multiply. With awareness of the conditions they thrive in, and a little care, summer parties can be safe. It is just a matter of following a few simple rules. Keep hot food hot and cold food cold and avoid leaving food in temperatures between 7C and 48C which is considered the danger zone as it offers bacteria optimum growth conditions. Watch out for flies too as they can transplant a source of poisoning from one food to another very easily. There are some really trendy and very attractive food-covers available now, which keep the flies out and are worth using. If you haven’t got food covers, keep lids on containers where possible.

The main cause of contamination, however, is not flies, but raw meat.

Once you have handled raw meat, particularly chicken, wash your hands, and all surfaces on which it was placed. It’s vital that raw meat is stored away from cooked meat. Remember an unwashed plate used to carry raw meat is dangerous if it’s then used to carry cooked meat to the table. And if you dry your hands on a tea towel having washed them after handling raw meat, remember that the tea towel will probably carry bacteria that can be passed to cooked food. Paper towels are safer as they are discarded after use.

Cooking at a high heat is the only positive way to kill bacteria and avoid food poisoning during the summer months. And never assume that if it is charred on the outside that it is cooked, particularly when you are handling chicken or meat that has been thawed from frozen. Always test the thickest parts of the chicken joints with a sharp knife before deciding it’s cooked. If the juices that escape are clear that’s fine, but if they are pink it certainly is not cooked sufficiently. Placing the knife blade in between the thigh bones is the best place to check as this is the thickest part of the chicken.

Foods and ingredients that should be treated with care in the warm include: l Dairy products — bacteria simply adore them and will multiply rapidly in a sandwich that contains butter l Yoghurt and cream are favourites too l Cooked rice is also dangerous when left in the danger zone for too long l Jugs of gravy and sauces should not be left in the sun too long either.

Bacteria love meat-based liquids and multiply rapidly if they find themselves swimming about in them. They double every ten minutes until their food supply diminishes.

Marinating is a popular way of adding flavour to your barbecued food, particularly as it helps retain moisture during cooking over hot coals, but don’t overdo it. It can also become a source of food poisoning. It’s vital to throw away the marinade mixture once it has been used. Don’t be tempted to use it for basting other meats, and particularly once it has been left in the danger zone. But don’t let any of this put you off staging a barbecue. It’s a great way of entertaining. Who can resist the aroma of grilled meat wafting through the air on a warm summer night? Regular hand washing with hot water and soap is the most effective way of ensuring your food is safe, and when washing down preparation areas and chopping boards, continually rinse the swab in hot water to avoid transferring bacteria from one place to another. It is not enough to just wipe over sticky surfaces with any moist rag that comes to hand.

As for what you cook at your barbecue, may I suggest you forget hamburgers and use your imagination to create exciting and unusual dishes served with tangy sauces and salsas that will turn the meal into something rather special.