Valorization of sugarcane vinasse for fungal biomass protein production: Potential application as fish feed ingredient

Abstract

The distilleries are among the major industries in the world generating vast amounts of sugarcane vinasse. The environmentally undesirable characteristics of vinasse become a matter of concern if it was considered that 10–15 L of a high organic load residue are generated per each liter of alcohol produced. Hence, elaborating new government policies for redirecting the final disposal of vinasse is becoming a requirement to ensure the sustainability of the distilleries in the long-term. Over the last few decades, fish farming has rapidly expanded to meet the increasing food demand associated with growing world’s population. However, a public debate over fish farming is its environmental sustainability as many fish species have high requirements for dietary protein. The conventional fish feed ingredients such as fishmeal and soybean meal are still widely used, but costly protein sources. Hence, dietary transition from conventional fish feeds towards alternative protein sources could contribute to a more predictable future market. Filamentous fungi are characterized by their capacity to grow on organic residues, providing large quantities biomass. Particularly, the cultivation of some filamentous fungi can result in a high-quality biomass (high protein levels) that can be used as feed ingredient added to the basal fish diet. Despite attributes of filamentous fungi, the main limitation for use of biomass in fish feed would be associated with the production of mycotoxins by some fungi species, representing an important fish health risk, but also on human health by consuming contaminated fish protein. The present chapter reviews the nutritional properties of fungal biomass produced from different organic byproduct/residues to be used with aquatic purposes. Besides, first advances on nutritional and toxicological aspects of fungus Aspergillus sp. V2 grown on vinasse for use as fish feed ingredient are also reviewed.