BACKGROUNDAs a result of the bovine spongiform encephalopathy (BSE) emergence, certain tissues of cattle are categorized as specified risk material (SRM) and completely banned from their traditional applications as an ingredient in animal feed, pet food, or fertilizer applications. The goal of this study was to investigate the hydrolysis of such hazardous proteinacious biomass and extract a safe proteinacious fraction to produce industrial feedstock for value-added applications. RESULTSThe SRM was hydrolyzed at subcritical temperatures of 180, 200, 220, 240, and 260 degrees C for 40min according to government-approved protocols. The recovery and cleavage of proteins and lipids, the generation and degradation of free and total amino acids, and the generation of organic acids were studied and found to be temperature-dependent. The yield of the hydrolyzed and recovered proteinacious fractions varied between 71.6 and 87.6% by weight of the original protein content in the SRM. The molecular size was also significantly dependent on the hydrolysis temperature. CONCLUSIONThe valorization of an otherwise waste SRM by subcritical hydrolysis and recovery techniques resulted in protein hydrolyzates suitable for bio-based chemicals and materials applications. The increase of temperature resulted in higher degrees of hydrolysis as shown by the smaller molecular size of hydrolyzed proteins. (c) 2014 Society of Chemical Industry