Spray-dried plasma (SDP) is very commonly used by pet food manufacturers as a binder in wet foods. SDP has higher gelling, water retention and emulsion properties than other binders.
More recently, pet food manufacturers have recognized that SDP also has the capacity to absorb quality differences from one batch of meat by-products raw material to the next.
According to PetFoodIndustry.com:
The animal by-products suppliers should consider the recommendation of using SDP in wet petfood recipes to avoid daily natural variations in their ingredient raw materials and also to avoid differences in product performance between fresh and frozen meat ingredients for wet petfood. Petfood producers should also consider the addition of a binder like SDP that could be regarded as a "safety belt" to warranty similar quality of their canned petfood on a regular basis.