Mealworm meal for animal feed: Environmental assessment and sensitivity analysis to guide future prospects

Abstract

This study assesses the environmental performance of mealworm (Tenebrio molitor) larvae meal via life cycle assessment (LCA) from cradle to mill gate. No LCA studies have yet assessed mealworm meal at the mill gate. Uncertainty and global sensitivity analyses were performed on the environmental performance of the system using four parameters that experts identify as critical to this performance: feed intake, electricity consumption at the farm stage, electricity consumption at the processing stage, and meal and oil yield at the processing stage. Results for the five impact categories assessed for one kg of mealworm meal are 141.3 MJ for cumulative energy demand, 3.8 kg CO2 eq for climate change, 25.6 g SO2 eq for acidification potential, 15.0 g PO4 eq for eutrophication potential, and 4.1 m2a for land use. Per kg of protein, these impacts are higher than those of soybean or fish meal. At the farm gate, our results for environmental impacts of mealworm larvae are similar to those provided by one study of the literature. The uncertainty analysis indicates coefficients of variation of approximately 20%. The global sensitivity analysis highlights that meal and oil yields are critical parameters that greatly influence variation in the environmental performance of the product. Feed intake and electricity consumption also have considerable influence on variation in the output. Several recent studies indicate that great improvements in zootechnical parameters of mealworms are expected, which should improve the latter's environmental performance. However, several macro-scale issues suggest that prospective and consequential LCAs are required to completely study the sector from an environmental perspective.