S13 - Session O4 - The future of frass: a sustainable fertilizer with biostimulation properties

Authors: Emmanuel Caron-Garant *, Aleena Massenet, Sébastien F. Lange, Christopher Warburton, Pierre Charbonneau

Across the western world, insect farming has recently become a blooming industrial sector. This rapid growth comes with new development challenges and opportunities. As a collegial research center specializing in bioproducts development, Biopterre has been focusing on the study and valorization of frass. This organic material is the main by-product generated by most insect production facilities. Generally considered a well-rounded "green" fertilizer, frass also shows potential as a biostimulation agent, due to its content in chitin/chitosan, beneficial microbes, and other bioactive components. To deepen our understanding of this unique product and optimize its usage parameters, Biopterre conducted various experiments including greenhouse trials (lettuce, peas, radishes, cucumber) and laboratory analysis such as metagenomics, ICP and respirometry. These tests revealed that all types of frass analyzed (mealworm, cricket, and black soldier fly) contain significant concentrations of chitin/chitosan. We also demonstrated that chitin content is superior before the product is sieved and consequently devoid of chitin-based exoskeletons. Genomics and respirometry confirmed the presence of various beneficial bacteria (linked to a rapid increase in CO 2 production when added to humidified growing medium). Results of our greenhouse experiments indicate that frass has fertilizing properties similar to those of other commercialized organic products. Flowering, rooting and immunity against insect pests also seem to be enhanced by the use of frass. As insect farming keeps getting more widespread and established in our society, the use of frass as an efficient and environmentally friendly fertilizer/biostimulant will surely take its place in mainstream agriculture. For this to happen, industry leaders and regulatory bodies need to keep working together towards a necessary balance between consumer satisfaction, sustainable development, and profitability. Thanks to its thriving horticultural sector including numerous growing medium and organic fertilizer producers, Eastern Canada is especially well positioned to play a prominent role in the future of frass. Acknowledgements: NSERC for their financial support