My family leaves the butter out on the counter. Isn't there any other danger other than rancidity? It doesn't last long, but it just seems really scary to me to leave an animal product out without refrigeration and say it's OK?
There is very little to worry about leaving butter out on the counter, although we do not recommend the practice. Butter is made from pasteurized milk, so unless there is gross contamination after pasteurizing (which almost never happens) the butter gets to your house in very safe condition. Butter has very little water in it (about 20%, which is not much in the world of food) and it has a fair amount of salt in it (about 5-10% in the water portion) so there is little danger of pathogen growth. Butter can support the growth of molds but it usually takes several weeks and ideal conditions to occur.
I am not aware of any outbreak of food-borne illness
associated with butter in the past 20 years. There are
some older cases, usually with unpasteurized butter,
causing outbreaks of Staphylococcus aureus. This is a
mild, flu-like disease that is almost never life
However, my recommendation is to store butter covered in the refrigerator between meals. It will significantly increase the shelf-live and virtually assure safety. On the other hand, do not worry too much about your family’s health related to un-refrigerated butter.
Source: Douglas Holt, Ph.D., Chair
of Food Science Program & State Extension Specialist for
Food Safety, University of Missouri-Columbia
Last update: Tuesday, May 05, 2009