In vitro bioaccessibility and characterisation of spent hen meat hydrolysate powder prepared by spray and freeze-drying techniques

Abstract

A detailed characterisation of spent hen meat hydrolysate (SMH) powders was done in this study. Briefly, SMH was obtained by enzymatic hydrolysis of whole spent hen meat of Indian layer bird breed (BV-300) using Flavourzyme® at optimised temperature (54 °C) and pH 6.6 for 30 min. The spray-dried (SD-SMH) hydrolysate powder showed significantly (p < 0.05) higher antioxidant activity (via the DPPH assay) than the freeze-dried (FD-SMH) hydrolysate powder, possibly due to the high level of sulphur-containing amino acids, as quantified by GC–MS/MS. The FD-SMH powder exhibited a higher average particle diameter (687 nm) and lower zeta potential (0.08 mV) than the SD-SMH powder (particle diameter =545 nm and zeta potential =–10.20 mV). Morphological analysis by scanning electron microscopy (SEM) corroborated significantly (p < 0.05) higher flowability of spray-dried powder (15.24; distinct spherical structure) than the freeze-dried powder (26.55; lamellar/shrivelled structure). The higher bioaccessibility of SD-SMH than FD-SMH depicted its preserved bioactivity, even after simulated gastrointestinal digestion. Overall, SD-SMH powder exerts the potential to be used in the food industry for its potential exploitation as a functional food ingredient or for nutraceutical applications.