Article: Temperatures higher than this allow bacteria the chance to grow and multiply. Use a thermometer to test the temperature if your fridge doesn't have an inbuilt thermometer. Place the thermometer in the fridge and leave the door closed for 5 minutes. Take the thermometer out after the 5 minutes are up and check the reading. There's no need to remove the packaging for this step as it actually helps the sausages defrost faster and more evenly while in the fridge. If you already removed the packaging, you can wrap the sausages in plastic wrap before placing them in the fridge.

What is a summary?
Test to make sure the temperature of the fridge is below 5 °C (41 °F). Leave the sausages in their packaging.