Vd 115

Aperture measurement involved randomly measuring 100 membrane pores on the surface image of electron micrograph with Nano Measure, and the average pore size D (nm) was calculated. The membrane porosity was measured by cutting each membrane sample into circular slices with a diameter of 2.5 cm, which were washed in ethanol and then soaked in deionized water for 24 h. The soaked membranes were removed and residual water on the membrane surface was gently wiped with dust-free paper. The mass of the wet sample was weighed and recorded as m₁. The wet membranes were dried in a vacuum drying oven (VD115, BINDER, Tuttlingen, Germany) at 60 °C until a consistent mass was obtained, m₂. The membrane porosity ε was calculated by Equation (1): $$\mathsf{\epsilon }=\frac{{\mathrm{m}}_1-{\mathrm{m}}_2}{\mathsf{\rho }·\mathrm{A}·\mathrm{d}}\times 100\%$$
where ε represents the porosity (%), m₁ and m₂ are the wet weight and dry weight (kg), ρ represents the density of water (kg m⁻²), A is the area (m²), and d is the thickness (m) of the membrane.

Grape pomace from Vitis vinfera L cv. Corvina, a red grape used for Amarone wine production, was kindly supplied by Tinazzi srl (Verona, Italy). The GP, after alcoholic fermentation, was separated, pressed, and immediately recovered and dried in a vacuum oven (VD 115 Binder GmbH, Tuttlingen, Germany) (40 °C, 30 kPa) until reaching a final moisture content of 11.0 g water/100 g GP. Afterwards, the stems and seeds were manually removed from the pomace and the by-product was milled (GM200 Retsch, Haan, Germany) to obtain a powder with a particle size < 0.2 mm. The GP was then stored in an airtight, dark plastic container until analyzed or used for pasta preparation. The GP chemical composition was assessed in triplicate according to the following AOAC standard methods: 930.15 for moisture, 976.05 for protein, 985.29 for total fiber, and 942.05 for ash content [19 ]. All chemical components were expressed as g/100 g of dry matter (DM).