Soybean Meal in Aquafeed

Soybean meal (SBM) is the most widely used plant protein source in commercial aquafeed, produced by solvent-extracting oil from defatted soy flakes; typical products contain 44-48% crude protein, about 0.5-2% residual fat, and 5-7% fiber. In fish feeds it is usually capped at 15-35% of the formula depending on species tolerance, because it contains heat-labile trypsin inhibitors, phytic acid (which binds phosphorus), saponins, and allergenic globulins that impair gut integrity in sensitive species such as early-stage salmonids and marine fish. Proper toasting destroys trypsin inhibitors, so under- or over-processed meal is a real quality risk. SBM replaces fish meal primarily on price and volume, but diets high in SBM require supplemental methionine and lysine, available phosphorus (phytase), and often attractants to keep intake and growth on target. Key purchasing metrics are protein content, urease activity, protein solubility in potassium hydroxide, and peroxide value. It sits alongside soy protein concentrate and rapeseed/canola meal as the main pillars of fish meal replacement strategies, and its inclusion rate is one of the biggest levers in least-cost formulation.