Solid state fermentation of camelina meal for improved animal feed

Abstract: Camelina sativa is an oilseed crop known for an array of environmental benefits when adapted as a cover crop. Camelina seeds have a high oil content (42-48%) which can be extracted and used as a biofuel. The resulting meal has potential applications as a feedstock for monogastric animals. However, compared to soybean meal- the current feed standard- camelina meal (CAM) has lower protein levels and higher concentrations of antinutritional factors (lignin, glucosinolates, phytate) which limits the use of CAM in monogastric animal diets. Breeding programs are underway to address some of these factors however, breeding programs also address a variety of agronomic traits so developing an additional approach will reduce breeding burdens. Solid state fermentation is a cost-effective and sustainable bioprocessing strategy that has been shown to improve the nutrient profile of other oilseed meals. In this study, a solid state fermentation strategy was developed to convert CAM to an improved feed ingredient by increasing protein levels and decreasing antinutritional factors. Fungal and bacterial species were screened by inoculating pure cultures on CAM and incubating at the ideal growth temperature for each organism under different fermentation lengths and moisture contents. The best candidates for solid state fermentation were identified: Saccharomyces cerevisiae increased amino acid concentration by 15% and Trametes versicolor degraded glucosinolates by 81% and phytate by 68% compared to a non-fermented control. Current work is being done to optimize fermentation conditions by identifying the ideal moisture content, particle size, fermentation length and effects of sequential and mixed culture fermentation. Optimization is expected to further enhance the nutritional profile of CAM. This data demonstrates the potential for S. cerevisiae and T. versicolor fermented camelina meal to be utilized as a feedstock for monogastric animals thereby increasing camelina’s economic return and potential to be adapted as a cover crop in Minnesota.