Optimization of pressure-assisted enzymatic treatment for fiber solubilization and structural modification of Korean cabbage by-products.

Korean cabbage by-products were treated using high-pressure enzyme treatment (HPET) to improve the solubilization and structural characteristics of ethanol-precipitable polysaccharide (EPP) fractions. Response surface methodology (RSM) and artificial neural network (ANN) models were employed to optimize enzyme concentration (0.5-2.0%), pressure (40-100 MPa), and treatment time (30-240 min). The optimal HPET condition (2% enzyme, 100 MPa, 210 min, 50 °C) increased the water solubility index from 46.55% to 64.61% and EPP yield from 3.85% to 5.52%, while reducing the water absorption index from 8.08 to 6.76 g/g compared with hot-water treatment. The proportion of the ≤10 kDa fraction increased to 85.80%, indicating enhanced polysaccharide depolymerization. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) suggested structural modifications in the recovered polysaccharide fraction. ANN showed predictive performance comparable to RSM. These findings demonstrate the potential of HPET for valorizing Korean cabbage by-products as functional polysaccharide ingredients.