Enzymatic Hydrolysis of Blue Whiting (Micromesistius poutassou); Functional and Bioactive Properties

Abstract

Functional and biochemical properties of fish protein hydrolysates (FPH) from blue whiting (BW) were studied. FPH (2.5%, 5%, 10%, and 15% degree of hydrolysis [DH]) were made from isolated proteins from headed and gutted BW with Alcalase 2.4 L. The properties of dried BW mince and protein isolate compared to 4 reference proteins (soy and milk protein) were studied: color, solubility, water-holding capacity (WHC), oil-binding capacity (OBC), emulsion capacity (EC), and emulsion stability (ES). The angiotensin I-converting enzyme (ACE) inhibitory activities of the soluble fraction of BW powders were also investigated. Furthermore, the products were characterized by analyzing their chemical composition. Chemical composition, solubility, OBC, and EC of the BW powders was significantly (P < 0.05) different with different DH, while color, ES, and WHC were not significantly (P > 0.05) different. Salt content of the FPH was high (4% to 19%) and increased with increased DH. Protein solubility varied from 10% to 70% and increased with increased DH. WHC of the FPH was around 97% and was higher than that of all the reference proteins tested. OBC decreased with increased DH (from 3.5 to 2.1 g oil/g protein) and was higher than OBC of the soy and milk proteins (1.6 to 1.9 g oil/g protein). EC of FPH was similar or lower than the reference proteins. ES of FPH (60% to 90%) was similar to or lower than soy and whey proteins (60% to 98%) but higher than casein (20%). ACE inhibition activity increased as DH was increased. Practical Application: The results from this study demonstrate that a functional bioactive hydrolysate can be produced from BW, which is an underutilized fish species, and may aid the industry in better utilizing this raw material. The novelty of this research was the use of BW as a raw material where the protein has been isolated with the pH shift method. Furthermore, it was novel that bioactivity and functionality was measured in the same samples.

Peptides: Production, bioactivity, functionality, and applications

“…Additionally, the balance of hydrophilic and hydrophobic forces of peptides is also mentioned as an important cause of solubility enhancement (Kristinsson and Rasco, 2000;Gbogouri et al, 2004). Several reported studies have also confirmed that increasing DH increases solubility of protein hydrolysates (Quaglia and Orban, 1987;Chobert et al, 1988a, b;Mutilangi et al, 1996;Linar es et al, 2000;Gbogouri et al, 2004;Klompong et al, 2007;Souissi et al, 2007;Balti et al, 2010;Geirsdottir et al, 2011). The solubility of the hydrolysates is especially improved at the proteins isoelectric point, pI (Chobert et al, 1988b).…”

“…During enzymatic hydrolysis, the presence of polar groups (-COOH and -NH2) increases, and it is assumed that this has a substantial effect on the increased WHC observed for hydrolysates (Balti et al, 2010). However, others stated that the DH did not affect the WHC (Geirsdottir et al, 2011). Additionally, Choi et al (2009) observed higher WHC of the insoluble fraction of protein hydrolysates than the soluble fraction.…”

“…Some studies have shown no effect of DH on the FAC (Amiza et al, 2012) or no correlation between DH and FAC (Souissi et al, 2007). Other studies reported improved FAC of hydrolysates at low DH and that further increment in DH significantly decreased FAC (Geirsdottir et al, 2011;Gbogouri et al, 2004;Balti et al, 2010;Garc ıa-Moreno et al, 2017). Low DH could even improve the FAC over the native protein (Balti et al, 2010, Mune, 2015.…”

Antioxidant and antimicrobial activities of squid ink powder

“…products like squid generally contained a high amount of protein where the majority of it composed with myofibrilar protein (80%), followed by myoplastic protein (12-20%) and the least was myostroma protein (2 -3%) which composed of collagen (Okuzumi and Fujii, 2000). The ability of the protein to function as an ingredient in food products depends on their functional properties such as amino acid composition and environmental factors including pH, temperature and ions present (Geirsdottir et al, 2011). The value of fat content in squid ink powder is slightly higher compared with raw squid which was about 1.0 to 2.0%, where the value considered lowest among all types of seafood (Okuzumi and Fujii, 2000).…”

The effects of pre-digested protein sources on the performance of early–mid stage Panulirus ornatus phyllosoma

“…As the acid denaturation reactions do not break the peptide bonds, the amino acid sequence remains the same (Fink et al 1994, Uversky andYuji, 2009). Alternatively, enzyme hydrolysis of protein cleaves peptide bonds, resulting in compounds of reduced molecular size (Geirsdottir et al, 2011;Jaenicke and Rudolph, 1990;Uversky and Yuji, 2009). Smaller peptide chains and FAAs are generally considered easier to absorb and thus increase the level of amino acids available for protein accretion (Buxbaum, 2007;Kaushik and Seiliez, 2010;Kvale et al, 2002).…”