Current animal-based protein sources such as meat, eggs and dairy are becoming increasingly expensive and unsustainable. Plant-based proteins are a more sustainable source of protein, which the food industry is interested in using in the future. Plant proteins can be incorporated into foods for their functional properties; prior to this, their characteristics such as solubility, swelling and emulsifying activity/stability need to be studied.
A research group from Heriot-Watt University in Edinburgh, UK, extracted and characterised the proteins from the seeds of the date fruit, which is currently a waste material. Using liquid-chromatography tandem mass spectrometry (LC-MS/MS), the team identified 90 unique proteins. A third of these proteins were involved in energy metabolism in the cell which is associated with the energy needed during germination and growth.
Two of the most abundant proteins identified were glycinin and β-conglycinin which are major storage proteins commonly found in seeds, particularly soy beans. Glycinin and β-conglycinin are known for their emulsifying properties; the team found the date seed proteins (DSP) to have slightly lower emulsifying properties compared to soy protein isolate (SPI). β-conglycinin has greater emulsifying properties compared to glycinin; the ratios of these two proteins may be responsible for the difference seen between the DSP and SPI.
Further studies of the characteristics of the DSP such as the solubility would be needed to establish if the protein would be suitable as a functional ingredient in food systems. Once more is known about the date seed proteins and their practical extractability from the hard seeds, the commercial viability of this protein source can be assessed.
Rssl.com