The shortage of pectin on the domestic market and the need for the rational use of secondary raw materials make the search for new sources of this polysaccharide a pressing issue. A promising raw material is de-alcoholized fruit and berry pomace from liqueur and vodka production, which is generated after the removal of alcohol-infused juices and retains up to 5% pectin substances on a dry-weight basis, since pectin is insoluble in alcohol and remains in the solid fraction. The aim of this work was to improve the technology for obtaining and concentrating pectin extract from de-alcoholized rowan pomace using membrane separation methods. A two-stage enzymatic-acid hydrolysis–extraction method was developed: in the first stage, the ground pomace was mixed with water at a solid-to-liquid ratio of 1:15, the enzyme preparation Rapidase Press was added at 40 U/g of pectin, and the mixture was kept at 50 °C and pH 4.0–4.3 for 2 hours; in the second stage, the extract was acidified with 10% hydrochloric acid to pH 2.0 and kept at 70 °C for 2 hours. To concentrate the resulting extract, a comparative analysis was performed using six ultrafiltration membranes of the UPM and UFM types, differing in permeability and globulin retention selectivity. Based on a set of parameters—concentration factor, pectin losses, and process stability—the UPM-20 membrane provided the best results, with a concentration factor of 2.93 and losses not exceeding 12%. The obtained pectin is classified as low-methoxyl (degree of esterification 49%) and is characterized by a complexing capacity of 157 mg Pb²⁺/g, a polyuronide content of 79%, carboxyl group content of 9.66%, acetyl group content of 1.05%, and pH 3.3. Based on the experimental data, a hardware-and-process flow diagram was proposed that eliminates the ethanol precipitation step and replaces vacuum evaporation with ultrafiltration concentration, thereby reducing energy consumption and eliminating the need for flammable and explosive organic solvents.

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