in beverage and food industries... for example, if you isolate a protein from yeast, alg or some other organism, you can use the protein in industry. how??
for example, ECGF (endotelial cell growth suplement) is necessary for some cell line proliferation, and it include some cytokines, cytokines are proteins ;))
for beverage industry, for example; energy drinks have some proteins, if you know the isolated protein has mission for awakeness, you can put it in the drink...
the important thing is what is mission of the isolated protein?? if you know the mission, you can use according to it....
SCPs are available commercially with Ranbaxy or Himalaya. The most common used is spirulina. It has about 90% digestve proteins and thus one of the best source of priotein.