Meat and fish fraud are global problems, costing consumers billions of dollars every year. On top of that, mislabeling products can cause problems for people with allergies, religious or cultural restrictions. Current methods to detect this fraud, while accurate, are slower than inspectors would like. Now, researchers reporting in ACS' Journal of Agricultural and Food Chemistry have optimized their handheld MasSpec Pen to identify common types of meat and fish within 15 seconds.