Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/17/2005
Publication Date: 7/14/2005
Citation: Sathivel, S., Smiley, S., Prinyawiwatkul, W., Bechtel, P.J. 2005. Functional and nutritional properties of red salmon (oncorhynchus nerka) enzymatic hydrolysates. Journal of Food Science. Vol. 70, NR.6, 2005 Interpretive Summary: The potential exists for the development of fish hydrolysate powders from Alaska by-products that can be used as ingredients in animal feeds and human foods. The objective of this study was to develop and characterize hydrolysate powders made from red (sockeye) salmon heads. This study demonstrated that the degree of hydrolysis and resulting peptide properties were affected by both digestion time and the type of commercial enzyme employed. Protein hydrolysates derived from red salmon heads are a good source of essential amino acids and minerals. Oil recovery from the salmon heads was somewhat affected by the kind of proteolytic enzymes used and the digestion time. The red salmon hydrolysate powders had desirable dark yellow color. Functional properties (solubility, fat adsorption, water adsorption, and emulsification stability) of the red salmon hydrolysates are consistent with potential applications as emulsifiers and binder agents. The red salmon hydrolysates could potentially compete with dairy and plant based protein hydrolysates and protein powders currently available in the market place.
Technical Abstract: The objective of this study was to develop and characterize hydrolysate powders made from red (sockeye) salmon heads. The effects of different proteolytic enzymes and different reaction durations (25, 50, 75 min) on functional and nutritional properties of red (sockeye) salmon head hydrolysates were evaluated. Degree of hydrolysis values for the 75-min digestion ranged from 6.4-16.7%. Oil yield (4.9-10.6 %) from red salmon heads was affected by the enzyme used. Protein hydrolysate powders were yellowish and contained 62.3-64.8% protein with high levels of essential amino acids. Increased degree of hydrolysis values were weakly correlated with increased hydrolysate solubility. Maximum emulsion stability and fat adsorption were observed for the dried hydrolysate generated in the 25-min reaction time. Water adsorption of hydrolysate powders ranged from 1.0-3.3 mL water/g dried hydrolysate. This study identified opportunities to develop value-added products from Alaska salmon processing byproducts.