Proposed study protocol: direct determination of K-40 in brewed coffee

This proposed study protocol presents a scientific approach for the direct determination of potassium-40 (K-40) activity in brewed coffee using high-resolution gamma-ray spectrometry. The study aims to establish a reproducible methodology for sample preparation, measurement, activity concentration calculation, and uncertainty assessment. Particular attention is given to the influence of coffee preparation methods, brewing conditions, and sample composition on K-40 activity in the final beverage. The protocol is intended to support radiation measurement research, natural radioactivity assessment in food and beverages, and the development of reliable experimental procedures for determining naturally occurring radionuclides in brewed coffee.