Hot and Cold
Prepare picnic food on the same day it is do be eaten, and then immediately freeze/refrigerate.
Experts suggest that food intended to be eaten cold should only be above 40 degrees for two hours. This is an aggregate number, meaning the prep time in your kitchen counts towards the two hour total. When prepping, keep items intended to be eaten cold out for as little as possible, and then put them in a shallow pan when returning to the fridge to shorten the time to return the food to a safe temperature.
Perishable items that have been out at the picnic for more than an hour, should be thrown away.
This is particularly true for items that have been handled by multiple people. Bacteria growth happens by a process of doubling. The longer a food is out, the more the bacteria has a chance to double. To make matters worse, if multiple people have handled the serving utensil, chances are additional bacteria has been introduced.
Keep hot foods hot
As cliché as it sounds, it has a purpose. Bacteria that causes food borne illness multiply between 40 degrees and 140 degrees, and THRIVE when the ambient temperature sits between 70 and 90 degrees. Generally speaking, picnic food can be kept out for up an hour in temperature ranges of 40 to 140 before it should be put either heated or cooled. Just because you return unsafe food to a temperature outside of danger zone, it doesn’t necessarily make the food safe.
Ice always goes on top, and around, and behind, and in front of your food. When packing your cooler, you should generally pack perishables in as much ice, by volume, as the item being cooled, and then some. The type of ice doesn’t matter, what matters is that you surround your food with as much ice as possible. The only exception is underneath your food. Since cold air falls, keep the ice on top.
Ice it up
Once the cooler has been packed, add ice as often as possible. Water doesn’t have the cooling power of ice, and once water starts forming, your food is getting closer and closer to the danger zone.
Keep items that need to be cooked in a separate cooler from items that will be served cold.
In commercial fridges, meat goes on the bottom shelf to prevent accidental drips onto food that won’t be cooked. It’s no different in your cooler. As ice melts, the water comes in contact with the meat, thereby carrying potential food-borne bacteria to other cooler occupants. If everything is going to be cooked, the bacteria will be killed. In cases of fruits, veggies, and other items that won’t be cooked, pack a separate cooler.
Transport your Cooler properly
The trunk of your car can reach temperatures of 150 degrees. If possible, keep the cooler inside the cabin of your car where the air conditioning will help your ice do its job.
Mayonnaise based foods
In its natural state, mayonnaise is acidic enough to handle being left out longer than most foods. However, once the mayonnaise is combined with other foods, such as macaroni, potatoes, and shellfish, its self preservation properties are useless. In fact, combining these foods may actually make them MORE dangerous than when left separate. The solution. Keep it all cold!!