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

Area of Science:

• Food Science
• Analytical Chemistry
• Entomology

Background:

• Edible insects are a sustainable protein source entering the European novel foods market.
• Accurate analytical methods are crucial for consumer safety, fraud prevention, and regulatory compliance.
• Rapid and sensitive techniques are needed for identifying insect species in various food products.

Purpose of the Study:

• To evaluate matrix-assisted laser desorption/ionisation time of flight mass spectrometry (MALDI-TOF MS) for insect authentication in food.
• To develop and apply species-specific mass spectrometry (MS) databases for insect identification.
• To assess the method's efficacy in identifying insect species in both model mixtures and commercial food products.

Main Methods:

• Insect species identification using trypsin digestion and MALDI-TOF MS.
• Purification of samples using ZipTip C18.
• Development of a structured query language-based search for m/z values.
• Validation with six model mixtures and ten commercial food products.

Main Results:

• MALDI-TOF MS successfully authenticated genus and species in model mixtures with dominant insect proteins.
• Identification accuracy decreased with closely related species or complex spectral profiles.
• Commercial products with high insect content were adequately identified.
• Low-insect-content products (<10%) with high plant protein content resulted in ambiguous or incorrect species assignments.

Conclusions:

• MALDI-TOF MS is effective for rapid genus-level insect identification and species discrimination in simple matrices.
• Accurate species identification is influenced by insect abundance and food matrix complexity.
• Complementary methods like LC-MS/MS may be necessary for unambiguous identification in complex or low-insect-content foods.