A fungal process to enhance the nutritional value of soybean meal for fish and weaning livestock

We developed a fungal process to remove anti-nutritional factors (ANFs) from soybean meal (SBM), while enhancing the protein content, amino acid balance, and digestibility of protein. The goal is to replace fish meal (FM) in feed applications requiring high quality protein. FM is considered the “gold standard” in aquaculture, weaning livestock, and companion animal feeds, but unfortunately, FM harvest has been stable for decades. The annual 7-9% growth of aquaculture now consumes over 70% of the FM supply, causing prices to exceed $2,000/ton. Our process uses Aureobasidium pullulans to convert sugars and indigestible oligosaccharides into cell mass, increasing the protein content of SBM from 48-50% to 65-70%. The process also degrades trypsin inhibitors, saponins, and other ANFs. For example, trypsin inhibitor activity decreased from 8,407 TIU/g in SBM to <100 TIU/g in our microbially enhanced protein (ME-PRO^TM) product. ME-PRO has successfully replaced FM in several highly controlled and replicated trials in yellow perch, trout, salmon, and barramundi. Growth, feed efficiency, and fish health data demonstrated high performance in comparison to more costly ingredients. In trials with weaning pigs, ME-PRO performed similarly to FM in all performance metrics, and pigs fed ME-PRO had lower rates of post-weaning diarrhea syndrome compared to control-fed pigs. ME-PRO was used to replace SBM in conventional versus accelerated growth milk replacer diets in dairy calves, resulting in better growth performance and feed efficiency. Continued process improvements and application experimentation with other food animals should establish even broader utilization value of ME-PRO in relation to fish meal.