Chitooligosaccharides from squid pen prepared using different enzymes: characteristics and the effect on quality of surimi gel during refrigerated storage

Abstract

Chitooligosaccharides (COS) from squid pen produced using amylase, lipase and pepsin were characterized. COS produced by 8% (w/w) lipase (COS-L) showed the maximum FRAP and ABTS radical scavenging activity than those prepared using other two enzymes. COS-L had the average molecular weight (MW) of 79 kDa, intrinsic viscosity of 0.41 dL/g and water solubility of 49%. DPPH, ABTS radical scavenging activities, FRAP and ORAC of COS-L were 5.68, 322.68, 5.66 and 42.20 μmol TE/g sample, respectively. Metal chelating activity was 2.58 μmol EE/g sample. For antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of COS-L against the targeted bacteria were in the range of 0.31-4.91 mg/mL and 0.62-4.91 mg/mL, respectively. Sardine surimi gel added with 1% (w/w) COS-L showed the lower PV, TBARS and microbial growth during 10 days of storage at 4°C. COS-L from squid pen could inhibit lipid oxidation and extend the shelf-life of refrigerated sardine surimi gel.

Effect of Psyllium (Plantago ovata Forks) Husk on Characteristics, Rheological and Textural Properties of Threadfin Bream Surimi Gel

“…The slight decrease in BF with the addition of PHP at higher concentrations was likely caused by the dilution of MPs in surimi. Generally, various interactions with either covalent or noncovalent bonds are formed during the setting phenomenon at 40 °C, in which endogenous TGase plays a major role in the cross-linking of a myosin heavy chain (MHC) via formation of the non-disulfide bond [ε-(γ-glutamyl) lysine linkage], thus strengthening the gel network [ 13 , 14 ] regardless of PHP incorporation. DF was decreased with the addition of PHP, and the lowest value was obtained for SPH-3 and SPH-4 ( p < 0.05).…”

“…Calcium ions have been implemented to enhance TGase activity, leading to higher protein cross-linking via non-disulfide covalent bonds [ 8 ]. Plant phenolics [ 9 , 10 ] or cross-linking enzymes e.g., microbial TGase [ 11 , 12 ] or chitooligosaccharide [ 13 , 14 ] have been used in surimi. In addition, some hydro-colloids have been employed into surimi to strengthen the gel with high water-holding capacity (WHC) [ 1 , 15 , 16 ].…”

Pacific white shrimp ( Litopenaeus vannamei ) shell chitosan and the conjugate with epigallocatechin gallate: Antioxidative and antimicrobial activities

“…ORAC assay determines the oxidative degradation of the fluorescent molecule azo‐initiator compounds (Singh et al., 2019b). Heating of the azo initiator produces peroxyl radicals, which break the fluorescent molecule, causing loss of fluorescence (Francenia Santos‐Sánchez et al., 2019).…”

“…Furthermore, the free amino groups of chitosan can accept H‐ion from the system, which then subsequently reacted with free radicals. Additionally, OH‐groups present at carbon number 3 and 6 could function as H‐donors to radicals (Singh et al., 2019b). Therefore, conjugation of EGCG at carbon number 2 or 3 or 6 of CS‐130‐4 increased the number of OH‐groups, thereby increasing antioxidant activities.…”

“…ORAC assay determines the oxidative degradation of the fluorescent molecule azo-initiator compounds (Singh et al, 2019b).…”