SBIR Phase II: A Microbially-Based Process to Produce a High-Quality Soy Protein Concentrate for Complete Fish-Meal Replacement in Aquaculture Diets

This Small Business Innovation Research (SBIR) Phase I project will develop a process to produce high quality soy protein concentrate (HQSPC) as a fish meal replacer in aquaculture feeds, while providing a binding agent for extrusion and an immunoprophylactic for disease control. Increased demand for fish protein and reduced wild captured fish has facilitated rapid growth of aquaculture (9% per year). This has dramatically increased demand for fish meal (the primary component in aquaculture feeds), causing overexploitation of this resource and rapidly escalating prices. There is considerable market opportunity for a high quality, economical plant protein concentrate to completely replace fish meal in aquaculture feeds, thus providing broad impact. The proposed innovation is a microbially-based process to economically produce HQSPC by converting soybean carbohydrates into protein, yield an exopolysaccharide for pellet binding, and provide an immunoprophylactic. Phase II objectives include generating sufficient quantities of HQSPC for feeding trials with yellow perch to assess technical and economic feasibility. The HQSPC is anticipated to have>70% protein to replace fish meal, while providing desirable growth rates and conversion efficiencies. Bench-scale production costs should be less than current SPC ($0.30/lb), but with an intrinsic value closer to that of soy protein isolate ($1.50/lb). The broader impact/commercial potential of this project is to improve the nation?s second largest trade deficit for natural resources, fish protein, by providing a complete fish meal replacement. Soybean meal or soy protein concentrates (SPC) have been used to partially replace fish meal, however the solvent extraction process used to produce SPC is expensive, the separated oligosaccharides do not have a valuable use, and the quality of SPC (65% protein) is insufficient to permit complete replacement of fish meal. Soy protein isolate (90% protein) requires a more costly protein extraction method. The proposed microbial process converts soybean carbohydrates into additional protein, along with sufficient gum to serve as a binding agent, and a probiotic to induce an immunostimulant effect. Preliminary data shows the proposed microbe will metabolize the individual carbohydrates in soybeans, which will enhance scientific and technological understanding of this mechanism. To demonstrate technical and commercial feasibility, extrusion and enzymatic saccharification will be used to solubilize carbohydrates in soybean white flake, followed by incubation with the gum producing microbe, and recovery of solids for use in yellow perch feeding trials. International aquaculture feed manufacturers would be prospective customers for the HQSPC or the conversion process itself.