Functional protein rich extracts from bovine and porcine hearts using acid or alkali solubilisation and isoelectric precipitation

Alkali solubilisation (ALS) was compared with acid solubilisation (ACS) for preparation of protein rich extracts from bovine and porcine hearts. ACS and ALS recovered 51.53%–55.74% of the total protein from bovine and porcine hearts. All extracts were rich in myofibrillar proteins with both treatments resulting in reductions in fat, collagen and cholesterol contents compared with starting materials. At 0% NaCl, ACS and ALS extracts had good gelling properties with the ALS gels having lower % cook loss. While treatments did not affect gel hardness, ACS extracts formed gel networks with higher storage modulus after heating and cooling. At 2% NaCl gel hardness, % cook loss and storage modulus values increased, with greater increases occurring for ACS extracts. The results show that ALS- and ACS-based processes have potential to produce functional ingredients for processed meat products.