Can you leave butter icing at room temperature?

Butter icing, also known as American buttercream, should not be left at room temperature for an extended period. Butter icing is made with butter, sugar, milk or water, and flavouring, and it is susceptible to spoilage and melting at room temperature.

Here are the reasons why you should not leave butter icing at room temperature:

1. Spoilage: Butter is a dairy product and is prone to spoilage when left at room temperature. Bacteria can grow in the butter, causing it to become rancid and develop an unpleasant taste and smell. Spoiled butter icing can be harmful to consume.

2. Melting: Butter melts at a relatively low temperature, around 35 degrees Celsius (95 degrees Fahrenheit). If the room temperature is higher than this, the butter icing will start to melt and become soft and runny. This can affect the texture, consistency, and appearance of the icing.

3. Separation: Butter icing is an emulsion of fat (butter), water, and sugar. When left at room temperature, the water and fat components can separate, causing the icing to become grainy and curdled. This can affect the overall quality and taste of the icing.

For these reasons, it is recommended to store butter icing in the refrigerator to maintain its freshness, texture, and safety. Butter icing can be stored in an airtight container in the refrigerator for up to 2 weeks. When you need to use it, let it come to room temperature for about 15-30 minutes before using, or microwave it for a few seconds on low power just until spreadable.