Some people like peanut butter in sandwiches. Other people mix it in desserts or feed it to squirrels. Now there is a new use for peanut butter — as a quality assurance tool. The National Institute of Standards and Technology (NIST) recently issued Standard Reference Material (SRM) 2387, a peanut butter sample that has been characterized with state-of-the-art measurement methods to provide values for the amount of fat, protein, vitamins, minerals and other analytes it contains. It is one of a series of food-matrix SRMs that can be used by food manufacturers to validate production and quality control procedures as well as ensure accurate labeling of product content.