Pilot plant extraction of potato proteins and their structural and functional properties

Abstract

In the present study, three processes were scaled-up to pilot scale environment for the isolation of potato proteins from imitation by-products of potato fruit juice and potato pulp. Precipitation with (NH4)2SO4 saturation and isolation by a multi-enzymatic system resulted in an improved protein recovery yield from 8.4 (for subsequent-ultrafiltration) to 27.2% and 13.3%, respectively. In terms of protein profile, all extracts showed similar recovery of patatin, with a wide difference in the recovered protease inhibitors. Structurally all isolation processes had an effect on the secondary structure of the isolated proteins, where multi-enzymatic system-based isolation process resulted in a higher presence of carbohydrates, which had a preservation effect against denaturation after heat treatments. The protein concentrate recovered upon the multi-enzymatic system treatment exhibited statistically improved techno-functionality in terms of emulsifying activity index. Emulsion and foam stabilities were comparable among all isolation techniques. This study is expected to broaden the applications of the targeted plant-based protein ingredients and to take advantage of their associated functional and health benefits.