Production of corn zein microparticles with loaded lysozyme directly extracted from hen egg white using spray drying: Extraction studies

Feasibility of achieving sustained release of lysozyme by encapsulation in corn zein using spray drying was examined. To reduce the materials cost, this part of work focused on partially purifying lysozyme from hen egg white using 30–90% (v/v) aqueous ethanol, adjusted to pH 3.0–9.24. After extraction for up to 24 h and centrifugation, the purification performance was evaluated for the supernatant. Extraction was insignificantly affected by kinetics (P = 0.6186) but was inefficient at pH above 5.0 and above 60% ethanol. The optimal extraction was achieved at 50% ethanol and pH 3.5. Further, most of the lysozyme precipitated from the 50% ethanol (at pH 3.5) extract after increasing ethanol concentration to 90% but was completely recovered after diluting the precipitate back to 50% ethanol. Findings from this work may lead to low-cost encapsulation technologies using partially-purified lysozyme, such as spray drying.