Whey is an expensive product but well accepted in sports nutrition. However for a universally appealing product particularly weight management it cannot be claimed as “suitable for vegetarians”. There will be an increased interest in that category.
Whey protein does give the best amino acid profile for a complete protein. Soya is quite good too. There are a lot of article written about whey protein and soya giving rise to allergies and intolerance. So far there is little controversy about pea and rice. In combination they give a good complete protein profile.
They are both very digestible but perhaps lack the solubility of Whey . I have seen samples that give a good dispersion and bland taste. They could be combined and instantised to give a better dispersion.
The cost compared with whey protein is an advantage too.
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