ABSTRACT
LDN Labor Diagnostika Nord GmbH & Co. KG has developed an ELISA for the rapid semiquantitative or quantitative determination of histamine in different kinds of fish samples. Fresh/frozen tuna, canned tuna, fresh/frozen mahi mahi, canned sardines, and fish meal were used to validate the method under the requirements of the AOAC Research Institute Performance Tested Methods(SM) Program.The results all fell within the defined acceptance criteria. Linearity was given throughout the 0-300 ppm measuring range. Cross reactivity to similarly structured food spoilage indicators (tyramine and cadaverine) was minimal, less than 1%. Overall recoveries for all tested matrixes were within the determined acceptable range (80-120%), and the repeatability of precision was less than 10% overall and less than 5% at the defect action level of 50 ppm set by the U.S. Food and Drug Administration. The LOQ for the ELISA was determined to be 1.27 ppm. No lot-to-lot differences were observed. A 2-year claimed shelf life, at 2-8 °C, was confirmed through accelerated stability testing. After the introduction of minor procedural variations to the test, no differences in histamine levels were observed. Independent lab testing revealed that the ELISA works as well in the hands of minimally trained technicians as it does with expert developers. A strong correlation (r = 0.97) between the LDN ELISA and the AOAC 977.13 fluorometric method was observed. This study revealed that the LDN ELISA is equivalent to the AOAC Official Method 977.13 for the precise .and accurate measurement of histamine in fresh/frozen tuna, canned tuna, fresh/frozen mahi mahi, canned sardines, and fish meal.
