Whey Protein Concentrate (WPC)

Whey protein concentrate is what remains when enough non-protein solids are filtered out of sweet dairy whey — the liquid co-product of cheese making — to leave a dry powder of at least 25% protein. The ADPI Whey Protein Concentrate Standard v4.0 defines it that way and specifies production by physical separation such as membrane filtration, with no chemical extraction step. Grades are named for their protein: WPC 34 and WPC 80 are the two commercial anchors, with WPC 60 and WPC 70 supplied between them. What changes across that ladder is not only protein but lactose, which falls from roughly half the powder at WPC 34 to under a tenth at WPC 80, and ash, which falls with it. ADPI puts WPC 34 at 34.0–36.0% protein as-is (33.5% minimum) with 48.0–55.0% lactose, 3.0–4.5% fat and 6.5–8.0% ash; WPC 80 at 80.0–82.0% protein on the dry basis (79.5% minimum) with 4.0–10.0% lactose, 4.0–8.0% fat and 3.0–5.0% ash. Note the basis shift — for WPC 80 the protein figure is quoted on dry matter while every other value stays as-is, and that single detail decides the tariff heading. Moisture runs 3.0–5.0% with a 6.0% ceiling, pH sits at 6.0–6.7, and colour is white to cream with a bland, clean flavour. Protein is determined by AOAC 991.20 using the dairy factor N × 6.38. ADPI cites PDCAAS 1.00 and DIAAS 0.97 for WPC 80. Functionally, ADPI rates WPC 80 high for hydration rate, gelation and acid stability, and medium for emulsification, water binding and whipping — which is why it turns up as an egg or fat replacer, as a syneresis control in yoghurt and as a water binder in ice cream, as well as a straight protein source in ready-to-mix and ready-to-drink beverages, nutrition bars, bakery, confectionery, medical foods and infant formula bases. Instantised (lecithinated) grades wet out faster in dry mixes. Microbiological limits are standard plate count 30,000 CFU/g maximum, yeast and mould 100 CFU/g maximum, coliforms and Enterobacteriaceae 10 CFU/g maximum, with Salmonella, Listeria and coagulase-positive Staphylococcus not detected. This is a milk allergen and must be labelled as such.