Enhancing the bio-polymeric stabilization of spray-dried Chlorella phenolic-rich extract: Analysis of its physicochemical, functional, structural, and biological properties

In this study, the spray-drying process of Chlorella extract was investigated. The influence of different carriers including maltodextrin (MD), acacia gum (AG), whey protein concentrate (WPC) on the physicochemical, functional, flowability and color properties was analyzed. Powder obtained using MD revealed the highest bulk and tapped density (0.613 and 0.750 g/mL, respectively), the highest solubility (96.87 %) and hygroscopicity (29.87 %). Dry powder attained by MD, showed the highest content of total phenols (0.413 mg GAE/mL) and lowest particle size (12.70 μm). All produced powders revealed fair to good cohesiveness and flowability. Besides, the spray-drying processes using (MD -WPC) showed higher maintenance of the antioxidant activity. SEM images revealed the presence of particles of different sizes and wrinkles. Evaluation of the chemical structure (FTIR) indicated the encapsulation and distribution of the phenolic compounds of the extract in the matrix of the carriers. Research findings can confirm the possibility to use encapsulated Chlorella extracts as an abundant source of natural antioxidants in the enrichment and formulation of various beneficial food products. Finally, the results showed the efficiency of the spray-drying process on the production of dry powder extract of Chlorella with appropriate physical properties, stability and antioxidant properties

Technological, nutritional, and biological properties of apricot kernel protein hydrolyzates affected by various commercial proteases

Abstract The effect of enzymatic hydrolysis of apricot kernel protein with different proteases (Alcalase, pancreatin, pepsin, and trypsin) on the amino acid content, degree of hydrolysis (DH), antioxidant, and antibacterial characteristics of the resulting hydrolyzates was investigated in this study. The composition of amino acids (hydrophobic: ~35%; antioxidant: ~13%), EAA/TAA ratio (~34%), and PER index (~1.85) indicates the ability of the hydrolyzate as a source of nutrients and antioxidants with high digestibility. Enzymatic hydrolysis with increasing DH (from 3.1 to a maximum of 37.9%) led to improved solubility (especially in the isoelectric range) and changes in water‐ and oil‐holding capacity. The highest free radical scavenging activity of DPPH (83.3%), ABTS (88.1%), TEAC (2.38 mM), OH (72.5%), NO (65.7%), antioxidant activity in emulsion and formation of TBARS (0.36 mg MDA/L), total antioxidant (1.61), reducing power (1.17), chelation of iron (87.7%), copper (34.8%) ions, and inhibition of the growth of Escherichia coli (16.3 mm) and Bacillus cereus (15.4 mm) were affected by the type of enzymes (especially Alcalase). This research showed that apricot kernel hydrolyzate could serve as a nutrient source, emulsifier, stabilizer, antioxidant, and natural antibacterial agent in functional food formulations

Modification of Whey Proteins by Sonication and Hydrolysis for the Emulsification and Spray Drying Encapsulation of Grape Seed Oil

In this study, whey protein concentrate (WPC) was sonicated or partially hydrolyzed by Alcalase, then examined as an emulsifier and carrier for the emulsification and spray drying of grape seed oil (GSO)-in-water emulsions. The modification treatments increased the free amino acid content and antioxidant activity (against DPPH and ABTS free radicals), as well as, the solubility, emulsifying, and foaming activities of WPC. The modified WPC-stabilized emulsions had smaller, more homogeneous droplets and a higher zeta potential as compared to intact WPC. The corresponding spray-dried powders also showed improved encapsulation efficiency, oxidative stability, reconstitution ability, flowability, solubility, and hygroscopicity. The morphology of particles obtained from the primary WPC (matrix type, irregular with surface pores) and modified WPC (reservoir type, wrinkled with surface indentations), as well as the oxidative stability of the GSO were influenced by the functional characteristics and antioxidant activity of the carriers. Changes in the secondary structures and amide regions of WPC, as well as the embedding of GSO in its matrix, were deduced from FTIR spectra after modifications. Partial enzymolysis had better results than ultrasonication; hence, the WPC hydrolysates are recommended as emulsifiers, carriers, and antioxidants for the delivery and protection of bioactive compounds