What question did this study set out to answer?

This research examines how high-moisture extrusion impacts the nutritional quality of various plant protein sources.

March 10, 2026Open Access

Effects of high-moisture extrusion on the nutritional quality of protein isolates and concentrates from different sources

Key Points

This research examines how high-moisture extrusion impacts the nutritional quality of various plant protein sources.
Evaluated four plant protein ingredients: faba bean isolate, pea protein isolate, soy protein concentrate, and vital wheat gluten.
Assessed anti-nutritional factors, protein digestibility, amino acid scores, and mineral bioaccessibility using in vitro methods.
Measured changes in phenolic content, trypsin inhibitors, and soluble nitrogen after high-moisture extrusion.
High-moisture extrusion reduced phenolic content by 8-35% and trypsin inhibitors by 44-67%.
Protein digestibility improved in soy protein concentrate but not in others.
Amino acid scores declined slightly, with pea protein isolate showing the least reduction.

Abstract

• HME reduced phenolics and trypsin inhibitors in all ingredients but not phytic acid • Amino acid scores declined slightly upon HME, with pea protein isolate least affected • HME improved protein digestibility in soy, but not in other proteins • Mineral bioaccessibility remained stable upon HME Concerns have been raised over the nutritional adequacy of plant-based meat analogues, driven by the nutrient profile of their plant ingredients and their processed nature. To provide insights on the impact of processing on nutritional quality, this study evaluated the impact of high-moisture extrusion (HME) on anti-nutritional factors (ANFs), in vitro protein digestibility, amino acid score, and mineral bioaccessibility and soluble fraction in commercial plant protein ingredients: faba bean isolate (FBI), pea protein isolate (PPI), soy protein concentrate (SPC), and vital wheat gluten (VWG). The in vitro protein digestibility was assessed using the degree of hydrolysis (extent of peptide bond cleavage) and soluble nitrogen (release of total nitrogenous compounds). HME reduced the total phenolic content (8-35%) and trypsin inhibitor unit values (44-67%), while phytic acid levels remained stable. HME increased the degree of hydrolysis in PPI (5%), SPC (16%) and in VWG (75%). However, HME only increased the soluble nitrogen content in SPC (15%), whereas FBI, PPI, and VWG were unaffected despite the ANF reductions. This indicates that HME altered peptide size distribution rather than increasing total solubilized nitrogen, and consequently its overall impact on in vitro digestibility was limited. The amino acid scores declined slightly, with PPI showing the lowest reduction (0.9%) and mineral bioaccessibility and soluble fraction remained stable across most ingredients and minerals upon HME. This study provides an ingredient-specific overview of the nutritional effects of HME, demonstrating that the nutritional quality of the tested plant protein ingredients is shaped more by inherent properties than HME processing.

Read Full Paperexternally

KI fragen

Bookmark

View Full Paper