A method and kit for processing and testing powdered samples are provided herein. The powdered sample is combined with a fluid to produce a slurry or liquid suspension, and the slurry is contacted with an immunochromatographic test strip containing detectable reagents that are immunoreactive with an analyte to be detected in the sample. The method is particularly useful for the analysis of agricultural products or crops, such as the identification o f recombinant grains.
