Protein is an essential component of the human diet, and sustainable sources are a key requirement for Australian food security. Recently, consumer interest in socially responsible products as well as health and climate concerns have led to an increased interest in plant-based protein sources. Legumes such as lupin seeds, which were traditionally grown for soil nutrition or animal feed, are known to have a high protein content. Lupin seeds also possess nutritional and health benefits including the ability to lower cholesterol and blood pressure and regulate glucose levels.  

To ensure the viability of a crop as a global food source, the protein profile must be investigated to identify any possible allergens or undesirable proteins for consumption. This type of investigation requires standardised methods for extraction and analysis to ensure accurate and consistent results across crop varieties. In the case of lupin seeds, there are large amounts of fibre, carbohydrates, and fats, in addition to the high-protein content, which can render protein extraction difficult. The protein profile of lupin seeds has until recently remained relatively understudied, with no optimised extraction procedure available. 

Recently, CI Michelle Colgrave and PhD student Arineh Tahmasian published the first extensive investigation on the proteins in lupin seeds. The team used three different methods for extraction and employed sophisticated analysis techniques to determine the extraction efficiency of each solution. Each strategy was used across a range of lupin seed varieties including wild and domesticated crops. Computational methods were used to compare the protein profile of the lupin seed varieties. The team identified a particular extraction system that provided the most extensive protein profile and were able to identify a range of low abundance proteins across the crop varieties. Further studies will determine whether any of the identified proteins could pose a problem for human consumption. 

Importantly, CI Colgrave and her team reported an efficient work-flow method which could be applied to simultaneously measure thousands of protein levels in lupin seeds with high consistently and accuracy. The methods identified in this work will enable further examination of lupin seeds as a potential food source and could be applied to the investigation of other seeds or legumes.

The project represents an important output from our Flagship 1 within our Discover theme, as well as a key collaboration between Edith Cowan University and our partner CSIRO. 

Reference: Tahmasian, A., 2022, https://doi.org/10.1016/j.foodchem.2021.130722