The two-year Strategic Innovation Project brought together researchers from Wageningen University, Nizo and TNO as well R&D scientists from DSM and Darling Ingredients, to determine whether protein processing is always necessary, and to what degree.
Before it can be used as an ingredient, protein – be it plant or animal-based – must be purified using processes that are expensive as well as being energy- and water-intensive.
“But our research shows that such intensive purification is not necessary for all applications," said project leader and senior researcher at Wageningen Food and Biobased Research Marcel Meinders.
The conclusion could result in big savings for ingredient suppliers. Hugo Streekstra, principal scientist at DSM said: “Proteins are usually purified extensively, and without further insight it [was] assumed that the most purified product is the best – and the most expensive.”
The project focussed on proteins extracted from potatoes, blood plasma and peas, while DSM investigated canola (rapeseed) protein.
Thanks to the findings, manufacturers will get new ingredients with different degrees of purity and a better understanding of their functionality, protein functionality expert at Nizo Fred van de Fred said.
Darling Ingredients, which transforms beef, poultry and pork by-product streams into usable, specialty ingredients, also took part in the project in order to better understand blood plasma.
Fred Beekmans, director of R&D and quality, said: “The water solubility and gel-forming ability of blood proteins decrease above a certain temperature or humidity. For the first time, we are now able to measure this under controlled conditions."
The NYSE-listed supplier, which operates under a number of global brands including Rousselot and Peptan, said it would use the findings to improve quality and preservation of its blood plasma protein ingredients during long distance transport.
On the back of this success, a follow-up project with the Protein Competence Centre is already in the pipeline, with DSM and other companies turning their attention to aggregation dynamics, synergies and the digestibility of proteins in less purified protein mixtures.
Why do proteins need to be purified anyway?
Van de Fred explained: “Proteins are never the sole ingredient in a source material, for example, a pea seed contains mostly starch and a soy bean mostly oil. Purifying the protein means removing the other ingredients.”
This results in a protein ingredient that can be used for a specific purpose, either for its nutritional qualities – which is determined by its digestibility and amino acid composition, in particular, essential amino acids – and its functional properties.
The type of functionality required by manufacturers depends on the kind of food or drink they are creating but, in general, proteins are used for their solubility as well as gelling, emulsifying and foaming capabilities.
These properties can be quickly lost, however, when they mix with other proteins or if the acidity of the food matrix changes. This means manufacturers need to purify them.
When an ingredient contains less than 50% protein it is classified as a flour or milled seed. When it has up to 75% protein it is a protein concentrate and if it has more than 80% protein of dry matter it is a protein isolate.