Portable NIR spectrometer and FTIR and soft modelling to authenticate edible cricket, mealworm and buffalo worm flour

Abstract

Population growth has increased the search for new food sources. Edible insects offer an environmentally sustainable option for high-quality proteins and lipids from agricultural waste. However, their high value makes them vulnerable to adulteration, highlighting the need for reliable authentication to ensure product integrity and protect consumers from potential allergens. This study evaluated two portable NIR spectrometers (900–1700 nm and 1450–2450 nm) and a benchtop FTIR device (4000–550 cm−1) for authenticating edible insect flours (buffalo worm, cricket, and mealworm) sold in the UK. Soft modelling methods were used, including Data-Driven Soft Independent Modelling Class Analogy (DD-SIMCA) and soft Partial Least Squares Discriminant Analysis (sPLS-DA), as they suit authentication tasks. Principal Component Analysis (PCA) showed that spectral data of pure insect flours were clustered in the scores plot. DD-SIMCA achieved 100 % sensitivity (SNS) in the test set using FTIR for all insects. NIR Spectrometer in the range of 1450–2450 nm reached 100 % SNS and 100 % specificity (SPS) for buffalo worm and mealworm flour. sPLS-DA showed class sensitivity (CSNS) between 75 % and 100 %, for all three devices tested, with spectrometer in the range of 1450–2450 nm reaching class efficiency rate (CEFF) and total efficiency (TEFF) values ranging from 93 % to 100 %. Also, PLSR achieved RMSEP values as low as 0.44 %, demonstrating its robustness as a tool. In conclusion, this study highlights IR spectroscopy with soft modelling as a novel, non-destructive solution for authenticating insect flours, filling the current gap in rapid and reliable analytical tools for this emerging industry.</p