Strategies for controlling over-puffing of 3D-printed potato gel during microwave processing

Abstract Starch-based printed foods are very sensitive to rapid heating using microwaves because microwave energy accelerates gelatinization of starch and formation of the gel network, which enhances the ability of foods to hold water vapor, resulting in the over-puffing problem of printed samples. Insoluble dietary fiber extracted from soybean residue (SIDF, soybean insoluble dietary fiber) and modification of the internal structure provided a solution to the over-puffing problem. Experimental results showed that incorrect addition and particle size of SIDF caused excess puffing or hardening. SIDF addition of 10% (w/w) and particle size of 150–180 μm provided better crispness while maintaining the product shape. The effect of SIDF on expansion rate was attributed to reduced mobility of moisture, enhanced mechanical strength, and declined deformation ability of potato gel. Internal structures with parallel lines and high porosity should be selected and the maximum internal filling density was generally less than 70%. Besides controlling deformation, it added value of soybean residue by incorporating into 3D-printed puffed potato chips.