Plant protein ingredients

Astract

Research on plant-based proteins is still in its early stages. The effects of manufacturing processes on their chemical composition (nutritive and potentially ‘anti-nutritive’ components), on their techno-functional and on their sensory properties are not yet fully understood. Additionally, the influence of different processing levels on the nutritional quality remains unclear, as does the question of whether plant proteins are truly more sustainable than conventional animal proteins. Within the NewFoodSystems Innovation Space, three projects aim to shed light on these questions: ‘Sustainable protein ingredients’, ‘AlProPlant’ and ‘Pr:Ins – Holistic assessment’. Findings of these projects are presented in this article.

Introduction

Ensuring a sustainable supply of high-quality food for the world‘s growing population requires a significant increase in food production. As competition for available arable land continues to intensify, new land-saving production concepts are needed. Given the high resources and land consumption associated with animal product production, alternative protein sources are increasingly being explored. Plant proteins could serve as one such alternative [1], provided they are at least comparable, if not superior, to animal proteins in terms of techno-functional and sensory properties, nutritional quality, and sustainability [2].

When discussing plant proteins and so-called alternative products made from them, it is first necessary to define what exactly is meant by the term ‘plant proteins’. In principle, plant proteins are proteins, derived from plant sources. However, the food industry does not use pure proteins, but protein ingredients, which differ significantly in their protein content and in the concentration of accompanying substances. Depending on their protein
content, these ingredients are classified as flours (less than 50%), concentrates (50–80%), and isolates (over 80%). A precise definition exists only for soy protein ingredients [3].

The differences in protein content are caused by the respective production processes. Flours, for example, undergo minimal processing, as the seeds are only dehulled and ground. In some cases, particularly with high-fat raw materials such as soy and lupin, a de-oiling step is also performed [4]. In protein concentrates, the protein content is further increased by grinding and air separation or by removing accompanying substances by means of extraction. The production of protein isolates undergo the most intensive processing, typically involving aqueous alkaline extraction followed by purification through isoelectric precipitation or ultrafiltration [5]. This approach allows for protein contents above 80% while simultaneously removing undesirable accompanying substances that may affect sensory properties and nutritional quality.

The protein ingredients mentioned above differ not only in their protein content but also considerably in their techno-functional and sensory properties, nutritional quality, and sustainability profile ( Figure 1). Price differences should also be emphasized, with flours being the least expensive, followed by concentrates and isolates being the most costly due to the energy-intensive drying step required for their production. The food industry is willing to accept a higher price only if it is justified by the superior functionality of the ingredient. Research on plant-based proteins is still in its early stages. The effects of manufacturing processes on their chemical composition (nutritive and potentially ‘anti-nutritive’ components), on their techno-functional and on their sensory properties are not yet fully understood. Additionally, the impact of different processing levels on nutritional quality remains unclear, as does the question of whether plant proteins are truly more sustainable than conventional animal proteins. Within the NewFoodSystems Innovation Space, three projects aim to shed light on these questions: ‘Sustainable protein ingredients’, ‘AlProPlant’ and ‘Pr:Ins – Holistic assessment’. The findings of these projects are presented in this article. The aim is to highlight the various aspects of plant proteins that need to be considered in an objective and holistic discussion.

Download the full article as PDF here Plant protein ingredients

Schweiggert-Weisz U, Gola S, Bauer A, Diekmann C, Egert S, Brandt P, Früh S, Detzel A:
Plant protein ingredients. Between techno-functionality, sensory properties, human nutrition
and sustainability. Ernahrungs Umschau 2025; 72(5): 88–98.