Evaluating three fungal biomasses grown on diluted thin stillage as potential fish feed ingredients

Abstract

Thin stillage holds promise as a substrate for cultivating filamentous fungi. The suspended solids content of thin stillage directly influences biomass production. However, little attention has been given to its effects on fungal cultivation and composition, which is the focus of the current study. Various thin stillage dilutions were used to cultivate Zygomycete and Ascomycetes. Biomass and nutrient uptake were monitored during the cultivation. The harvested biomass was analyzed to assess nutrient composition in relation to fish dietary requirements. Thin stillage diluted to 75 % significantly enhanced fungal biomass production, with increases of 160 %, 213 %, and 235 % for A. oryzae, R. delemar, and N. intermedia, respectively. The harvested fungal biomass boasted approximately 50 % protein content, constituting 45 % essential amino acids. These findings underscore the potential of cultivating fungi in diluted thin stillage to boost biomass production and its high-quality nutritional composition positions it as a valuable candidate for fish feed formulations.