Rapid Identification of Edible Insect Species in Food Using MALDI-TOF Mass Spectrometry.

rationaleEdible insects are emerging as sustainable, nutritious 'foods of the future' and are gradually introduced to the European market as novel foods. Ensuring consumer safety and preventing fraud requires legal regulation, which in turn depends on reliable analytical methods. Sensitive, rapid techniques capable of identifying insect species are needed to support enforcement and monitoring of legislation across different food matrices.

methodsPowders of 10 insect species, including all four edible insects authorised as novel foods in the European Union, were digested with trypsin without toxic extraction agents. Samples were purified using ZipTip C

resultsSix model mixtures and 10 commercial products were authenticated using previously created genus- and species-specific m/z databases. Model mixtures with dominant insect proteins allowed correct genus- and species-level identification (7-20% peptide matches). Closely related species or dominant spectral components increased the misidentification. In the commercial products, identification was adequate for high-insect-content samples, but species assignment was ambiguous or incorrect in products with low insect content (7-10%) and high plant protein content.

conclusionsMALDI-TOF MS enables rapid genus-level insect identification and species-level discrimination, especially when dealing with unprocessed single-species powders. Accurate species assignment depends on insect abundance and matrix complexity of the inspected products. As well, the use of MALDI-TOF MS for species identification of products with low insect content or high plant protein is still limited and may require complementary methods such as LC-MS/MS to achieve unambiguous species identification.