Potential delivery of water-soluble protein hydrolysates to marine suspension feeders by three different microbound particle types

Abstract

Spray-dried zein particles (SDZP), spray-water zein particles (SWZP) and gelatin-alginate beads (GAB) were prepared containing a defined dietary mixture and their performances were compared for delivering the soluble fraction of protein hydrolysates. Measures of performances of these three different microbound particle (MBP) types included inclusion, encapsulation, retention and delivery efficiencies in addition to T 50 (time to 50% retention) values. SDZP had higher inclusion (IE) and encapsulation efficiencies (EE) compared to those of SWZP and GAB. A maximum IE of 66.60% and EE of 10.01% were achieved for SDZP. Although elimination of water from the manufacture process resulted in significantly higher inclusion and encapsulation efficiencies for SDZP, retention efficiencies and leakage profiles of all particle types were similar and followed a biphasic pattern with an initial burst release followed by a slower phase. Delivery of hydrolysates by SDZP was greater than for other MBP types with fifty percent of the initial hydrolysate retained after 36 min suspension in water. SDZP provides a more effective delivery vehicle for soluble protein hydrolysates than the other MBP types evaluated in this study. This, in turn, may help overcome limitations in the delivery of water-soluble nutrients and formulation of artificial diets for marine fish larvae and other suspension feeders.