Effects of heat treatments on the aromatic profile of edible insect species

• Blanching and sterilisation cause different impacts on the odour of the insects. • Changes in aroma profiles due to heat treatments among insect species. • High content of lipid oxidation products in Acheta domesticus . • Sterilization promotes furans formation and reduces phenols. Edible insects are emerging as a viable solution for future food chains. Sterilisation and blanching are thermal treatments commonly used during their processing. This research investigates the impact of these heat treatments on the aroma of various edible insect species, including Acheta domesticus, Locusta migratoria, Alphitobius diaperinus, Tenebrio molitor, Zophobas morio, Blaptica dubia and Galleria mellonella, by analysing their volatile compound profiles by HS-SPME-GC/MS. For raw and blanched insects, the aroma profiles differed substantially between species, while sterilised samples showed some common trends. Sterilisation results in significant changes, including increases in aldehydes and, in most insects, a decrease in carboxylic acids, as well as the development of furans and pyrazines, while blanching had less impact presenting spice-dependent changes. However, after both treatments, a decrease in the peak area of phenols, compounds that for its unpleasant odour are not aromatically desirable, was observed. This proves that heat treatments could influence the aroma profiles of insects and can therefore help to promote sensory quality by promoting the formation of compounds which enhance the aroma or remove disgusting odours. This research highlights the intricate relationship between heat treatments and the aroma of edible insects, shedding light on the potential for optimising their sensory characteristics for future food applications.