A review of alternative plant protein sources, their extraction, functional characterisation, application, nutritional value and pinch points to being the solution to sustainable food production

Abstract

SummaryProteins from animal sources have for many centuries been used as the conventional food proteins in the food industry to produce a variety of food products. This is mainly attributed to their functional properties that range from foaming ability and stability to emulsification and gelation. However, animal husbandry has a greater impact on the environment compared to crop production. Thus, research on the potential use of plant‐based proteins, which could be more sustainable, cheaper and environmentally friendly has continued to be the focus of many academics and the food industry. Even though studies have been carried out to investigate the functional properties of plant‐based protein sources, there is still a need to understand the challenges that exist in the extraction and the functional characteristics of proteins from plant sources, which could be used as a more feasible exchange for animal‐based proteins. Therefore, this review aims to contribute to the existing knowledge on the extraction, characterisation and functional properties of plant‐based proteins. To this end, relevant literature was searched on several databases such as EBSCO HOST and Science Direct. Google Scholar was also used as a complementary search engine. Research that has addressed the extraction and functional characterisation of proteins from plant sources was critically evaluated and the findings are discussed herein. Additionally, the pinch points that exist in the use of plant‐based proteins as alternatives to animal proteins in food processing are highlighted in this review.

Dairy, Plant, and Novel Proteins: Scientific and Technological Aspects

“…However, plant proteins contain a higher level of bioactive compounds, like phytonutrients (e.g., carotenoids, flavonoids, isoflavones, etc. ), which can play an important role in the prevention of several diet-related diseases, such as cancer [179].…”

“…However, deliberate process-induced modifications can be conducted to improve the protein functionality, including enzymatic modification, extrusion, high-pressure processing, high-power ultrasound treatment, etc. [176,179,[183][184][185]. Extrusion, particularly, can align the protein fibers and create a meat-like structure [185].…”

“…Accordingly, the flavor of plant proteins and the ingredient applications made with them have remained critical obstacles for consumer acceptability [197]. Different ingredients, like flavor enhancers and bitter-taste inhibitors, can be added during the manufacturing process to improve the flavor [179]. However, this is not ideal for the "clean-label" trend that consumers desire [198].…”

Plant‐based foods as meat and fat substitutes

“…In food processing, it is common that when one ingredient is being removed, there is a need to replace this with an alternative that has similar techno‐functional properties as the one that is being replaced. Most of the time when proteins from animals are removed and replaced with those of plant origin, given the fact that plant‐based proteins tend to have a lower solubility and nutritional value than those of animal origin, other additives that have various functional roles such as binding the ingredients together are always added during product formulation (Munialo, 2023 ). There is also the issue of taste where plant‐based proteins tend to have some odd flavor notes (Ismail et al, 2020 ), which results in the use of additives (with some additives being added to mask these off flavors and tastes).…”

“…Additionally, meat is still viewed and believed by many people to be an important and necessary part of a balanced and healthy diet which is mainly related to enjoyment, taste, and habit (Santo et al, 2020 ). Thus, one would then wonder if increasing awareness and educating the public is vital as this would then involve the modification of the dietary habits of people, and consequently, there will be more willingness to consume and purchase plant‐based meat and fat substitutes (Munialo, 2023 ). In general, the success of the meat and fat substitutes market is determined by how well these products are received by consumers globally.…”